Efficacy of extended-release tramadol for treatment of prescription opioid withdrawal: A two-phase randomized controlled trial*

PubMed Central

Lofwall, Michelle R.; Babalonis, Shanna; Nuzzo, Paul A.; Siegel, Anthony; Campbell, Charles; Walsh, Sharon L.

2013-01-01

Background Tramadol is an atypical analgesic with monoamine and modest mu opioid agonist activity. The purpose of this study was to evaluate: 1) the efficacy of extended-release (ER) tramadol in treating prescription opioid withdrawal and 2) whether cessation of ER tramadol produces opioid withdrawal. Methods Prescription opioid users with current opioid dependence and observed withdrawal participated in this inpatient, two-phase double blind, randomized placebo-controlled trial. In Phase 1 (days 1-7), participants were randomly assigned to matched oral placebo or ER tramadol (200 or 600 mg daily). In Phase 2 (days 8-13), all participants underwent double blind crossover to placebo. Breakthrough withdrawal medications were available for all subjects. Enrollment continued until 12 completers/group was achieved. Results Use of breakthrough withdrawal medication differed significantly (p<0.05) among groups in both phases; the 200 mg group received the least amount in Phase 1, and the 600 mg group received the most in both phases. In Phase 1, tramadol 200 mg produced significantly lower peak ratings than placebo on ratings of insomnia, lacrimation, muscular tension, and sneezing. Only tramadol 600 mg produced miosis in Phase 1. In Phase 2, tramadol 600 mg produced higher peak ratings of rhinorrhea, irritable, depressed, heavy/sluggish, and hot/cold flashes than placebo. There were no serious adverse events and no signal of abuse liability for tramadol. Conclusions ER tramadol 200 mg modestly attenuated opioid withdrawal. Mild opioid withdrawal occurred after cessation of treatment with 600 mg tramadol. These data support the continued investigation of tramadol as a treatment for opioid withdrawal. PMID:23755929

Ondansetron does not prevent physical dependence in patients taking opioid medications chronically for pain control.

PubMed

Chu, Larry F; Rico, Tom; Cornell, Erika; Obasi, Hannah; Encisco, Ellen M; Vertelney, Haley; Gamble, Jamison G; Crawford, Clayton W; Sun, John; Clemenson, Anna; Erlendson, Matthew J; Okada, Robin; Carroll, Ian; Clark, J David

2018-02-01

In this study, we investigated the co-administration of ondansetron with morphine, and whether it could prevent the development of physical dependence in patients taking opioids for the treatment of chronic pain. A total of 48 chronic back pain patients (N = 48) participated in this double-blinded, placebo-controlled, randomized study. Patients were titrated onto sustained-release oral morphine and randomized to take 8 mg ondansetron or placebo three times daily concurrently with morphine during the 30-day titration. Following titration, patients underwent Naloxone induced opioid withdrawal. Opioid withdrawal signs and symptoms were then assessed by a blinded research assistant (objective opioid withdrawal score: OOWS) and by the research participant (subjective opioid withdrawal score: SOWS). We observed clinically significant signs of naloxone-precipitated opioid withdrawal in all participants (ΔOOWS = 4.3 ± 2.4, p < 0.0001; ΔSOWS = 14.1 ± 11.7, p < 0.0001), however no significant differences in withdrawal scores were detected between treatment groups. We hypothesized that ondansetron would prevent the development of physical dependence in human subjects when co-administered with opioids, but found no difference in naloxone-precipitated opioid withdrawal scores between ondansetron and placebo treatment groups. These results suggest that further studies are needed to determine if 5HT 3 receptor antagonists are useful in preventing opioid physical dependence. Copyright © 2017 Elsevier B.V. All rights reserved.

Open-label dose-finding trial of buprenorphine implants (Probuphine) for treatment of heroin dependence.

PubMed

White, Jason; Bell, James; Saunders, John B; Williamson, Paul; Makowska, Maria; Farquharson, Aaron; Beebe, Katherine L

2009-07-01

Buprenorphine, a mu-opioid receptor partial agonist, has been shown to be safe and effective for treatment of opioid dependence. A novel implantable formulation of buprenorphine (Probuphine), using a polymer matrix sustained-release technology, has been developed to offer treatment for opioid dependence while minimizing risks of patient noncompliance and illicit diversion. The goal of the current study was to conduct an initial, open-label, evaluation of the safety, pharmacokinetics, and efficacy of two doses of Probuphine in subjects with opioid dependence maintained on sublingual buprenorphine. Two doses of Probuphine were evaluated in 12 heroin-dependent volunteers switched from daily sublingual buprenorphine dosing to either two or four Probuphine implants based upon their buprenorphine daily maintenance dose of 8 mg or 16 mg respectively, and were monitored for 6 months. Probuphine implants provided continuous steady state delivery of buprenorphine until their removal at 6 months. Withdrawal symptoms and craving remained low throughout the 6 months. For the 12 subjects, an average of 59% of urines were opioid-negative across the 6 month treatment period. Injection site reactions were present in half of patients, but none were serious. No safety concerns were evident. These results suggest that Probuphine implants offer significant promise for enhancing delivery of effective opioid substitution treatment while minimizing risk for abuse of medication.

Rational use of opioids.

PubMed

Mastronardi, P; Cafiero, T

2001-04-01

The role of analgesia and sedation in intensive care units (ICU) is ancillary to other intensive care strategies, nevertheless they permit that every other diagnostic and therapeutic procedure is safely performed by keeping the patient pain-free, anxiety-free and cooperative. Commonly used opioids in ICU include morphine, fentanyl, sufentanil and remifentanil. The choice among opioid drugs relies on their pharmacokinetics and their pharmacodynamic effects. Cardiovascular stability observed with fentanyl and sufentanil indicates their use in hemodynamically compromised patients. Short-acting remifentanil offers several advantages in patients requiring prolonged infusions. The organ-independent metabolism of this newer molecule may be valuable in patients with multiple organ failure. The main indications for opioid analgesia and sedation in ICU include: 1) Anxiety, pain and agitation: in turn, they can increase cardiac workload, myocardial oxygen consumption and rate of dysarrhythmias; 2) immediate postoperative period after major surgery; 3) short-term invasive procedures. Potential advantages offered by opioids in the ICU setting also include: a) Cardiac protection: in animal models, it has been observed that delta-opiate receptor stimulation confers a preconditioning-like protective effects against myocardial ischemia; b) Neuroprotection: recent studies suggest that mu- and kappa-opiate receptors are involved in ischemic preconditioning against seizures in the brain. During opioid therapy in the ICU, drug tolerance and withdrawal symptoms should be anticipated and the dose adjusted accordingly.

Palonosetron and Hydroxyzine Pre-treatment Reduces the Objective Signs of Experimentally-Induced Acute Opioid Withdrawal in Humans: A Double-Blinded, Randomized, Placebo-Controlled Crossover Study

PubMed Central

Erlendson, Matthew; D'Arcy, Nicole; Encisco, Ellen; Yu, Jeff; Rincon-Cruz, Lorena; Peltz, Gary; Clark, J. David

2017-01-01

Background Treatments for reducing opioid withdrawal are limited and prone to problematic side effects. Laboratory studies, clinical observations, and limited human trial data suggest 5-HT3-receptor antagonists and antihistamines may be effective. Objectives This double-blind, crossover, placebo-controlled study employing an acute physical dependence model evaluated whether (i) treatment with a 5-HT3-receptor antagonist (palonosetron) would reduce opioid withdrawal symptoms, and (ii) co-administration of an antihistamine (hydroxyzine) would enhance any treatment effect. Methods At timepoint T=0, healthy (non-opioid dependent, non-substance abuser) male volunteers (N=10) were pre-treated with either a) placebo, b) palonosetron IV (0.75 mg), or c) palonosetron IV (0.75 mg) and hydroxyzine PO (100 mg) in a crossover study design. This was followed at T=30 by intravenous morphine (10mg/70kg). At T=165, 10mg/70kg naloxone IV was given to precipitate opioid withdrawal. The objective opioid withdrawal score (OOWS) and subjective opioid withdrawal score (SOWS) were determined 5 and 15 minutes after naloxone administration (T=170, 180, respectively). Baseline measurements were recorded at T=-30 and T=-15. Results Comparison of average baseline OOWS scores with OOWS scores obtained fifteen minutes after naloxone was significant (p=0.0001). Scores from fifteen minutes post-naloxone infusion showed significant differences in OOWS scores between treatment groups: placebo, 3.7 ± 2.4; palonosetron, 1.5± 0.97; and palonosetron with hydroxyzine, 0.2 ± .1333. Conclusions Pretreatment with palonosetron significantly reduced many signs of experimental-induced opioid withdrawal. Co-administration with hydroxyzine further reduced opioid withdrawal severity. These results suggest that 5-HT3 receptor antagonists, alone or in combination with an antihistamine, may be useful in the treatment of opioid withdrawal. PMID:27712113

Discovery of a novel site of opioid action at the innate immune pattern-recognition receptor TLR4 and its role in addiction.

PubMed

Jacobsen, Jonathan Henry W; Watkins, Linda R; Hutchinson, Mark R

2014-01-01

Opioids have historically, and continue to be, an integral component of pain management. However, despite pharmacokinetic and dynamic optimization over the past 100 years, opioids continue to produce many undesirable side effects such as tolerance, reward, and dependence. As such, opioids are liable for addiction. Traditionally, opioid addiction was viewed as a solely neuronal process, and while substantial headway has been made into understanding the molecular and cellular mechanisms mediating this process, research has however, been relatively ambivalent to how the rest of the central nervous system (CNS) responds to opioids. Evidence over the past 20 years has clearly demonstrated the importance of the immunocompetent cells of the CNS (glia) in many aspects of opioid pharmacology. Particular focus has been placed on microglia and astrocytes, who in response to opioids, become activated and release inflammatory mediators. Importantly, the mechanism underlying immune activation is beginning to be elucidated. Evidence suggests an innate immune pattern-recognition receptor (toll-like receptor 4) as an integral component underlying opioid-induced glial activation. The subsequent proinflammatory response may be viewed akin to neurotransmission creating a process termed central immune signaling. Translationally, we are beginning to appreciate the importance of central immune signaling as it contributes to many behavioral actions of addiction including reward, withdrawal, and craving. As such, the aim of this chapter is to review and integrate the neuronal and central immune signaling perspective of addiction. © 2014 Elsevier Inc. All rights reserved.

Opioids, pain, the brain, and hyperkatifeia: a framework for the rational use of opioids for pain.

PubMed

Shurman, Joseph; Koob, George F; Gutstein, Howard B

2010-07-01

Opioids have relieved more human suffering than any other medication, but their use is still fraught with significant concerns of misuse, abuse, and addiction. This theoretical article explores the hypothesis that opioid misuse in the context of pain management produces a hypersensitivity to emotional distress, termed hyperkatifeia. In the misuse of opioids, neural substrates that mediate positive emotional states (brain reward systems) are compromised, and substrates mediating negative emotional states (brain stress systems) are enhanced. A reflection and early marker of such a nonhomeostatic state may be the development of opioid-induced hyperkatifeia, defined as the increased intensity of the constellation of negative emotional/motivational symptoms and signs observed during withdrawal from drugs of abuse (derived from the Greek "katifeia" for dejection or negative emotional state) and is most likely to occur in subjects in whom the opioid produces a break with homeostasis and less likely to occur when the opioid is restoring homeostasis, such as in effective pain treatment. When the opioid appropriately relieves pain, opponent processes are not engaged. However, if the opioid is administered in excess of need because of overdose, pharmacokinetic variables, or treating an individual without pain, then the body will react to that perturbation by engaging opponent processes in the domains of both pain (hyperalgesia) and negative emotional states (hyperkatifeia). Repeated engagement of opponent processes without time for the brain's emotional systems to reestablish homeostasis will further drive changes in emotional processes that may produce opioid abuse or addiction, particularly in individuals with genetic or environmental vulnerability.

The combination very low-dose naltrexone-clonidine in the management of opioid withdrawal.

PubMed

Mannelli, Paolo; Peindl, Kathleen; Wu, Li-Tzy; Patkar, Ashwin A; Gorelick, David A

2012-05-01

The management of withdrawal absorbs substantial clinical efforts in opioid dependence (OD). The real challenge lies in improving current pharmacotherapies. Although widely used, clonidine causes problematic adverse effects and does not alleviate important symptoms of opioid withdrawal, alone or in combination with the opioid antagonist naltrexone. Very low-dose naltrexone (VLNTX) has been shown to attenuate withdrawal intensity and noradrenaline release following opioid agonist taper, suggesting a combination with clonidine may result in improved safety and efficacy. We investigated the effects of a VLNTX-clonidine combination in a secondary analysis of data from a double-blind, randomized opioid detoxification trial. Withdrawal symptoms and treatment completion were compared following VLNTX (.125 or .25 mg/day) and clonidine (.1-.2 mg q6h) in 127 individuals with OD undergoing 6-day methadone inpatient taper at a community program. VLNTX was more effective than placebo or clonidine in reducing symptoms and signs of withdrawal. The use of VLNTX in combination with clonidine was associated with attenuated subjective withdrawal compared with each medication alone, favoring detoxification completion in comparison with clonidine or naltrexone placebo. VLNTX/clonidine was effective in reducing symptoms that are both undertreated and well controlled with clonidine treatment and was not associated with significant adverse events compared with other treatments. Preliminary results elucidate neurobiological mechanisms of OD and support the utility of controlled studies on a novel VLNTX + low-dose clonidine combination for the management of opioid withdrawal.

The Combination Very Low-Dose Naltrexone–Clonidine in the Management of Opioid Withdrawal

PubMed Central

Mannelli, Paolo; Peindl, Kathleen; Wu, Li-Tzy; Patkar, Ashwin A.; Gorelick, David A.

2013-01-01

Background The management of withdrawal absorbs substantial clinical efforts in opioid dependence (OD). The real challenge lies in improving current pharmacotherapies. Although widely used, clonidine causes problematic adverse effects and does not alleviate important symptoms of opioid withdrawal, alone or in combination with the opioid antagonist naltrexone. Very low-dose naltrexone (VLNTX) has been shown to attenuate withdrawal intensity and noradrenaline release following opioid agonist taper, suggesting a combination with clonidine may result in improved safety and efficacy. Objectives We investigated the effects of a VLNTX–clonidine combination in a secondary analysis of data from a double-blind, randomized opioid detoxification trial. Methods Withdrawal symptoms and treatment completion were compared following VLNTX (.125 or .25 mg/day) and clonidine (.1–.2 mg q6h) in 127 individuals with OD undergoing 6-day methadone inpatient taper at a community program. Results VLNTX was more effective than placebo or clonidine in reducing symptoms and signs of withdrawal. The use of VLNTX in combination with clonidine was associated with attenuated subjective withdrawal compared with each medication alone, favoring detoxification completion in comparison with clonidine or naltrexone placebo. VLNTX/clonidine was effective in reducing symptoms that are both undertreated and well controlled with clonidine treatment and was not associated with significant adverse events compared with other treatments. Conclusions and Scientific Significance Preliminary results elucidate neurobiological mechanisms of OD and support the utility of controlled studies on a novel VLNTX + low-dose clonidine combination for the management of opioid withdrawal. PMID:22233189

Opioid Tapering in Fibromyalgia Patients: Experience from an Interdisciplinary Pain Rehabilitation Program.

PubMed

Cunningham, Julie L; Evans, Michele M; King, Susan M; Gehin, Jessica M; Loukianova, Larissa L

2016-09-01

Despite current guideline recommendations against the use of opioids for the treatment of fibromyalgia pain, opioid use is reported in approximately 30% of the patient population. There is a lack of information describing the process and results of tapering of chronic opioids. The purpose of this study is to describe opioid tapering and withdrawal symptoms in fibromyalgia patients on opioids. This retrospective research study included a baseline analysis of 159 patients consecutively admitted to the Mayo Clinic Pain Rehabilitation Center from 2006 through 2012 with a pain diagnosis of fibromyalgia completing a 3-week outpatient interdisciplinary pain rehabilitation program. Opioid tapering analysis included 55 (35%) patients using daily opioids. Opioid tapering was individualized to each patient based on interdisciplinary pain rehabilitation team determination. Opioid withdrawal symptoms were assessed daily, utilizing the Clinical Opioid Withdrawal Scale. Patients taking daily opioids had a morphine equivalent mean dose of 99 mg/day. Patients on < 100 mg/day were tapered off over a mean of 10 days compared with patients on > 200 mg/day over a mean of 28 days (P < 0.001). Differences in peak withdrawal symptoms were not statistically significant based on the mean equivalent dose (P = 22). Patients taking opioids for <2 years did not differ in length of tapering (P =0.63) or peak COWS score (P =0.80) compared with >2 years duration. Patients had significant improvements in pain-related measures including numeric pain scores, depression catastrophizing, health perception, interference with life, and perceived life control at program completion. Fibromyalgia patients on higher doses of opioids were tapered off over a longer period of time but no differences in withdrawal symptoms were seen based on opioid dose. Duration of opioid use did not affect the time to complete opioid taper or withdrawal symptoms. Despite opioid tapering, pain-related measures improved at the completion of the rehabilitation program. © 2016 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Imaging Sex Differences in Regional Brain Metabolism during Acute Opioid Withdrawal

PubMed Central

Santoro, Giovanni C; Carrion, Joseph; Dewey, Stephen L

2017-01-01

The rate of opioid overdose continues to rise, necessitating improved treatment options. Current therapeutic approaches rely on administration of either a blocking agent, such as naloxone, or chronic treatment with replacement drugs, including methadone and/or buprenorphine. Recent findings suggest that males and females respond to these treatments uniquely. In an effort to better understand this sex-specific variation in treatment efficacy, we investigated the effects of acute opioid withdrawal in male and female rats using 18FDG and microPET. These data demonstrate that acute opioid withdrawal produces metabolic alterations in brain regions associated with reward and drug dependence, namely corpus striatum, thalamic nuclei, septum, and frontal cortex. Furthermore, certain changes are unique to males. Specifically, males demonstrated increased metabolism in the anterior cingulate cortex and the ventral hippocampus (CA3) following acute opioid withdrawal. If males and females exhibit sex-specific changes in regional brain metabolism following acute opioid withdrawal, then perhaps it is not surprising that they respond to treatment differently. PMID:29046888

Management of precipitated opiate withdrawal syndrome induced by nalmefene mistakenly prescribed in opiate-dependent patients: a review for clinicians.

PubMed

Franchitto, Nicolas; Jullian, Benedicte; Salles, Juliette; Pelissier, Fanny; Rolland, Benjamin

2017-06-01

Nalmefene, a long-acting µ-opioid antagonist approved to treat alcohol use disorder, is occasionally mistakenly prescribed to opiate-dependent or opioid-treated patients. We review recent literature on drug-drug interactions between nalmefene and opioids that lead to precipitated opioid withdrawal, and focus on its management and planning for care at discharge. Areas covered: This article provides a brief and comprehensive review of management of precipitated opioid withdrawal syndrome when nalmefene is associated with an opioid, whether misused or legally prescribed. Expert opinion: When treating an opiate-dependent patient with co-occurring alcohol use disorder, both conditions need to be a focus of clinical attention. New drugs for alcohol use disorder have been approved, but must be given cautiously and with a full understanding of their potential drug-drug interactions with opioid medications. Opiate-dependent patients should be intensively monitored for risk factors of alcohol use disorder and should be continuously motivated for treatment maintenance. When nalmefene is administered to opiate-dependent patients, acute opioid withdrawal syndrome may occur. Management of precipitated acute opioid withdrawal may include short or long-acting µ-opioid agonists during hospitalization, in addition to supportive treatment. The best management of polydrug abusers is based on a multidisciplinary approach, which should be pursued and improved through continuing medical education.

Reduction of opioid withdrawal and potentiation of acute opioid analgesia by systemic AV411 (ibudilast)

PubMed Central

Hutchinson, Mark R.; Lewis, Susannah S.; Coats, Benjamen D.; Skyba, David A.; Crysdale, Nicole Y.; Berkelhammer, Debra L.; Brzeski, Anita; Northcutt, Alexis; Vietz, Christine M.; Judd, Charles M.; Maier, Steven F.; Watkins, Linda R.; Johnson, Kirk W.

2009-01-01

Morphine-induced glial proinflammatory responses have been documented to contribute to tolerance to opioid analgesia. Here, we examined whether drugs previously shown to suppress glial proinflammatory responses can alter other clinically relevant opioid effects; namely, withdrawal or acute analgesia. AV411 (ibudilast) and minocycline, drugs with distinct mechanisms of action that result in attenuation of glial proinflammatory responses, each reduced naloxone-precipitated withdrawal. Analysis of brain nuclei associated with opioid withdrawal revealed that morphine altered expression of glial activation markers, cytokines, chemokines, and a neurotrophic factor. AV411 attenuated many of these morphine-induced effects. AV411 also protected against spontaneous withdrawal-induced hyperactivity and weight loss recorded across a 12-day timecourse. Notably, in the spontaneous withdrawal study, AV411 treatment was delayed relative to the start of the morphine regimen so to also test whether AV411 could still be effective in the face of established morphine dependence, which it was. AV411 did not simply attenuate all opioid effects, as co-administering AV411 with morphine or oxycodone caused 3-to-5-fold increases in acute analgesic potency, as revealed by leftward shifts in the analgesic dose response curves. Timecourse analyses revealed that plasma morphine levels were not altered by AV411, suggestive that potentiated analgesia was not simply due to prolongation of morphine exposure or increased plasma concentrations. These data support and extend similar potentiation of acute opioid analgesia by minocycline, again providing converging lines of evidence of glial involvement. Hence, suppression of glial proinflammatory responses can significantly reduce opioid withdrawal, whilst improving analgesia. PMID:18938237

A novel non-opioid protocol for medically supervised opioid withdrawal and transition to antagonist treatment.

PubMed

Rudolf, Gregory; Walsh, Jim; Plawman, Abigail; Gianutsos, Paul; Alto, William; Mancl, Lloyd; Rudolf, Vania

2018-01-01

The clinical feasibility of a novel non-opioid and benzodiazepine-free protocol was assessed for the treatment of medically supervised opioid withdrawal and transition to subsequent relapse prevention strategies. A retrospective chart review of DSM-IV diagnosed opioid-dependent patients admitted for inpatient medically supervised withdrawal examined 84 subjects (52 males, 32 females) treated with a 4-day protocol of scheduled tizanidine, hydroxyzine, and gabapentin. Subjects also received ancillary medications as needed, and routine counseling. Primary outcomes were completion of medically supervised withdrawal, and initiation of injectable extended release (ER) naltrexone treatment. Secondary outcomes included the length of hospital stay, Clinical Opiate Withdrawal Scale (COWS) scores, and facilitation to substance use disorder treatment intervention. Ancillary medication use and adverse effects were also assessed. A total of 79 (94%) of subjects completed medically supervised withdrawal. A total of 27 (32%) subjects chose to pursue transition to ER naltrexone, and 24 of the 27 (89%) successfully received the injection prior to hospital discharge. The protocol subjects had a mean length of hospital stay of 3.6 days, and the mean COWS scores was 3.3, 3.4, 2.8, and 2.4 on Day 1, 2, 3, and 4, respectively. Furthermore, 71 (85%) engaged in an inpatient or outpatient substance use disorder (SUD) treatment program following protocol completion. This retrospective chart review suggests the feasibility of a novel protocol for medically supervised opioid withdrawal and transition to relapse prevention strategies, including injectable ER naltrexone. This withdrawal protocol does not utilize opioid agonists or other controlled substances.‬‬‬‬.

Opioid interruptions, pain, and withdrawal symptoms in nursing home residents.

PubMed

Redding, Sarah E; Liu, Sophia; Hung, William W; Boockvar, Kenneth S

2014-11-01

Interruptions in opioid use have the potential to cause pain relapse and withdrawal symptoms. The objectives of this study were to observe patterns of opioid interruption during acute illness in nursing home residents and examine associations between interruptions and pain and withdrawal symptoms. Patients from 3 nursing homes in a metropolitan area who were prescribed opioids were assessed for symptoms of pain and withdrawal by researchers blinded to opioid dosage received, using the Brief Pain Inventory Scale and the Clinical Opioid Withdrawal Scale, respectively, during prespecified time periods. The prespecified time periods were 2 weeks after onset of acute illness (eg, urinary tract infection), and 2 weeks after hospital admission and nursing home readmission, if they occurred. Opioid dosing was recorded and a significant interruption was defined as a complete discontinuation or a reduction in dose of >50% for ≥1 day. The covariates age, sex, race, comorbid conditions, initial opioid dose, and initial pain level were recorded. Symptoms pre- and post-opioid interruptions were compared and contrasted with those in a group without opioid interruptions. Sixty-six patients receiving opioids were followed for a mean of 10.9 months and experienced a total of 104 acute illnesses. During 64 (62%) illnesses, patients experienced any reduction in opioid dosing, with a mean (SD) dose reduction of 63.9% (29.9%). During 39 (38%) illnesses, patients experienced a significant opioid interruption. In a multivariable model, residence at 1 of the 3 nursing homes was associated with a lower risk of interruption (odds ratio = 0.073; 95% CI, 0.009 to 0.597; P < 0.015). In patients with interruptions, there were statistically insignificant changes in mean (SD) pain score (difference -0.50 [2.66]; 95% CI, -3.16 to 2.16) and withdrawal score (difference -0.91 [3.12]; 95% CI, -4.03 to 2.21) after the interruption as compared with before interruption. However, when compared with patients without interruptions, patients with interruptions experienced larger increases in pain scores during the follow-up periods (difference 0.09 points per day; 95% CI, -0.01 to 0.019; P = 0.08). In particular, patients who received the highest quartile of opioid dose before interruption experienced increases in pain scores over time that were 0.22 points per day larger (95% CI, 0.02 to 0.41; P = 0.03) than those without interruption. Withdrawal scores were not associated with opioid interruption regardless of dose before interruption. Nursing home patients often experience interruptions in opioid dosing, which can be associated with worse pain, but not withdrawal symptoms, during acute illnesses. Clinicians should be aware of the potential risks and effects of opioid interruptions during acute illnesses in this patient group. Published by Elsevier Inc.

Withdrawal-associated injury site pain (WISP): a descriptive case series of an opioid cessation phenomenon.

PubMed

Rieb, Launette Marie; Norman, Wendy V; Martin, Ruth Elwood; Berkowitz, Jonathan; Wood, Evan; McNeil, Ryan; Milloy, M-J

2016-12-01

Withdrawal pain can be a barrier to opioid cessation. Yet, little is known about old injury site pain in this context. We conducted an exploratory mixed-methods descriptive case series using a web-based survey and in-person interviews with adults recruited from pain and addiction treatment and research settings. We included individuals who self-reported a past significant injury that was healed and pain-free before the initiation of opioids, which then became temporarily painful upon opioid cessation-a phenomenon we have named withdrawal-associated injury site pain (WISP). Screening identified WISP in 47 people, of whom 34 (72%) completed the descriptive survey, including 21 who completed qualitative interviews. Recalled pain severity scores for WISP were typically high (median: 8/10; interquartile range [IQR]: 2), emotionally and physically aversive, and took approximately 2 weeks to resolve (median: 14; IQR: 24 days). Withdrawal-associated injury site pain intensity was typically slightly less than participants' original injury pain (median: 10/10; IQR: 3), and more painful than other generalized withdrawal symptoms which also lasted approximately 2 weeks (median: 13; IQR: 25 days). Fifteen surveyed participants (44%) reported returning to opioid use because of WISP in the past. Participants developed theories about the etiology of WISP, including that the pain is the brain's way of communicating a desire for opioids. This research represents the first known documentation that previously healed, and pain-free injury sites can temporarily become painful again during opioid withdrawal, an experience which may be a barrier to opioid cessation, and a contributor to opioid reinitiation.

Safety of Oral Dronabinol During Opioid Withdrawal in Humans

PubMed Central

Jicha, Crystal J.; Lofwall, Michelle R.; Nuzzo, Paul A.; Babalonis, Shanna; Elayi, Samy Claude; Walsh, Sharon L.

2015-01-01

Background Opioid dependence remains a significant public health problem worldwide with only three FDA-approved treatments, all targeting the mu-opioid receptor. Dronabinol, a cannabinoid (CB) 1 receptor agonist, is currently under investigation as a novel opioid withdrawal treatment. This study reports on safety outcomes of dronabinol among adults in opioid withdrawal. Methods Twelve adults physically dependent on short-acting opioids participated in this 5-week within-subject, randomized, double blind, placebo-controlled inpatient study. Volunteers were maintained on oral oxycodone 30mg qid. Double-blind placebo substitutions occurred for 21 hours before each of 7 experimental sessions in order to produce opioid withdrawal. A single oral test dose was administered each session (placebo, oxycodone 30 and 60mg, dronabinol 5, 10, 20, and 30mg [decreased from 40mg]). Heart rate, blood pressure, respiratory outcomes and pupil diameter were assessed repeatedly. Results Dronabinol 40mg produced sustained sinus tachycardia accompanied by anxiety and panic necessitating dose reduction to 30mg. Sinus tachycardia and anxiety also occurred in one volunteer after dronabinol 20mg. Compared to placebo, dronabinol 20 and 30mg produced significant increases in heart rate beginning 1 hour after drug administration that lasted approximately two hours (p<0.05). Dronabinol 5 and 10mg produced placebo-like effects. Oxycodone produced prototypic mu-opioid agonist effects (e.g., miosis). Conclusion Dronabinol 20mg and higher increased heart rate among healthy adults at rest who were in a state of opioid withdrawal, raising concern about its safety. These results have important implications for future dosing strategies and may limit the utility of dronabinol as a treatment for opioid withdrawal. PMID:26483357

Opioid and GABAB receptors differentially couple to an adenylyl cyclase/protein kinase A downstream effector after chronic morphine treatment

PubMed Central

Bagley, Elena E.

2014-01-01

Opioids are intensely addictive, and cessation of their chronic use is associated with a highly aversive withdrawal syndrome. A cellular hallmark of withdrawal is an opioid sensitive protein kinase A-dependent increase in GABA transporter-1 (GAT-1) currents in periaqueductal gray (PAG) neurons. Elevated GAT-1 activity directly increases GABAergic neuronal excitability and synaptic GABA release, which will enhance GABAergic inhibition of PAG output neurons. This reduced activity of PAG output neurons to several brain regions, including the hypothalamus and medulla, contributes to many of the PAG-mediated signs of opioid withdrawal. The GABAB receptor agonist baclofen reduces some of the PAG mediated signs of opioid withdrawal. Like the opioid receptors the GABAB receptor is a Gi/Go coupled G-protein coupled receptor. This suggests it could be modulating GAT-1 activity in PAG neurons through its inhibition of the adenylyl cyclase/protein kinase A pathway. Opioid modulation of the GAT-1 activity can be detected by changes in the reversal potential of opioid membrane currents. We found that when opioids are reducing the GAT-1 cation conductance and increasing the GIRK conductance the opioid agonist reversal potential is much more negative than Ek. Using this approach for GABAB receptors we show that the GABAB receptor agonist, baclofen, does not couple to inhibition of GAT-1 currents during opioid withdrawal. It is possible this differential signaling of the two Gi/Go coupled G-protein coupled receptors is due to the strong compartmentalization of the GABAB receptor that does not favor signaling to the adenylyl cyclase/protein kinase A/GAT-1 pathway. This highlights the importance of studying the effects of G-protein coupled receptors in native tissue with endogenous G-protein coupled receptors and the full complement of relevant proteins and signaling molecules. This study suggests that baclofen reduces opioid withdrawal symptoms through a non-GAT-1 effector. PMID:25009497

Opioid and GABAB receptors differentially couple to an adenylyl cyclase/protein kinase A downstream effector after chronic morphine treatment.

PubMed

Bagley, Elena E

2014-01-01

Opioids are intensely addictive, and cessation of their chronic use is associated with a highly aversive withdrawal syndrome. A cellular hallmark of withdrawal is an opioid sensitive protein kinase A-dependent increase in GABA transporter-1 (GAT-1) currents in periaqueductal gray (PAG) neurons. Elevated GAT-1 activity directly increases GABAergic neuronal excitability and synaptic GABA release, which will enhance GABAergic inhibition of PAG output neurons. This reduced activity of PAG output neurons to several brain regions, including the hypothalamus and medulla, contributes to many of the PAG-mediated signs of opioid withdrawal. The GABAB receptor agonist baclofen reduces some of the PAG mediated signs of opioid withdrawal. Like the opioid receptors the GABAB receptor is a Gi/Go coupled G-protein coupled receptor. This suggests it could be modulating GAT-1 activity in PAG neurons through its inhibition of the adenylyl cyclase/protein kinase A pathway. Opioid modulation of the GAT-1 activity can be detected by changes in the reversal potential of opioid membrane currents. We found that when opioids are reducing the GAT-1 cation conductance and increasing the GIRK conductance the opioid agonist reversal potential is much more negative than E k . Using this approach for GABAB receptors we show that the GABAB receptor agonist, baclofen, does not couple to inhibition of GAT-1 currents during opioid withdrawal. It is possible this differential signaling of the two Gi/Go coupled G-protein coupled receptors is due to the strong compartmentalization of the GABAB receptor that does not favor signaling to the adenylyl cyclase/protein kinase A/GAT-1 pathway. This highlights the importance of studying the effects of G-protein coupled receptors in native tissue with endogenous G-protein coupled receptors and the full complement of relevant proteins and signaling molecules. This study suggests that baclofen reduces opioid withdrawal symptoms through a non-GAT-1 effector.

Investigation of the Interactions between Methadone and Elvitegravir-Cobicistat in Subjects Receiving Chronic Methadone Maintenance

PubMed Central

Winkle, P.; Custodio, J. M.; Wei, X.; Rhee, M. S.; Kearney, B. P.; Ramanathan, S.; Friedland, Gerald H.

2013-01-01

Interactions between HIV and opioid dependence therapies are known to occur. We sought to determine if such interactions occurred between methadone and elvitegravir boosted with cobicistat (EVG/COBI). We performed a within-subject open-label pharmacokinetic and pharmacodynamic study of 11 HIV-seronegative subjects stabilized on at least 2 weeks of methadone. Subjects underwent baseline and steady-state evaluation of the effect of elvitegravir 150 mg once a day (QD) boosted with 150 mg QD of cobicistat (EVG/COBI) on methadone pharmacokinetic parameters. Safety and pharmacodynamics were monitored throughout the study. Compared to baseline values, the R-methadone mean area under the concentration-time curve to the end of the dosing period (AUCtau) (5,550 versus 6,210 h · ng/ml) and mean maximum concentration of drug in serum (Cmax) (316 versus 337 ng/ml) did not significantly increase in the presence of EVG/COBI. Compared to baseline values, the S-methadone mean AUCtau (7,040 versus 7,540 h · ng/ml) and mean Cmax (446 versus 452 ng/ml) did not significantly increase in the presence of EVG/COBI. The AUCtau, Cmax, and Ctau of elvitegravir and cobicistat did not significantly differ from those of historical controls. Opioid withdrawal or overdose was not observed among subjects in this study. The addition of EVG/COBI to stabilized patients receiving methadone did not affect methadone pharmacokinetics and pharmacodynamics. These two agents can be safely coadministered. PMID:24080665

Pioglitazone attenuates the opioid withdrawal and vulnerability to relapse to heroin seeking in rodents.

PubMed

de Guglielmo, Giordano; Kallupi, Marsida; Scuppa, Giulia; Demopulos, Gregory; Gaitanaris, George; Ciccocioppo, Roberto

2017-01-01

Relapse to opioids is often driven by the avoidance of the aversive states of opioid withdrawal. We recently demonstrated that activation of peroxisome proliferator-activated receptor gamma (PPARγ) by pioglitazone reduces the motivation for heroin and attenuates its rewarding properties. However, the role of PPARγ in withdrawal and other forms of relapse to heroin is unknown. To further address this issue, we investigated the role of PPARγ on the development and expression of morphine withdrawal in mice and the effect of pioglitazone on several forms of heroin relapse in rats. We induced physical dependence to morphine in mice by injecting morphine twice daily for 6 days. Withdrawal syndrome was precipitated on day 6 with an injection of naloxone. In addition, different groups of rats were trained to self-administer heroin and, after the extinction, the relapse was elicited by cues, priming, or stress. The effect of different doses of pioglitazone was tested on these different paradigms. Data show that chronic and acute administration of pioglitazone attenuates morphine withdrawal symptoms, and these effects are mediated by activation of PPARγ receptors. Activation of PPARγ by pioglitazone also abolishes yohimbine-induced reinstatement of heroin seeking and reduces heroin-induced reinstatement, while it does not affect cue-induced relapse. These findings provide new insights on the role of PPARγ on opioid dependence and suggest that pioglitazone may be useful for the treatment of opioid withdrawal in opioid-addicted individuals.

Emotional Impairment and Persistent Upregulation of mGlu5 Receptor following Morphine Abstinence: Implications of an mGlu5-MOPr Interaction

PubMed Central

Zanos, Panos; Georgiou, Polymnia; Gonzalez, Loreto Rojo; Hourani, Susanna; Chen, Ying; Kitchen, Ian; Kieffer, Brigitte L; Winsky-Sommerer, Raphaelle

2016-01-01

Background: A difficult problem in treating opioid addicts is the maintenance of a drug-free state because of the negative emotional symptoms associated with withdrawal, which may trigger relapse. Several lines of evidence suggest a role for the metabotropic glutamate receptor 5 in opioid addiction; however, its involvement during opioid withdrawal is not clear. Methods: Mice were treated with a 7-day escalating-dose morphine administration paradigm. Following withdrawal, the development of affective behaviors was assessed using the 3-chambered box, open-field, elevated plus-maze and forced-swim tests. Metabotropic glutamate receptor 5 autoradiographic binding was performed in mouse brains undergoing chronic morphine treatment and 7 days withdrawal. Moreover, since there is evidence showing direct effects of opioid drugs on the metabotropic glutamate receptor 5 system, the presence of an metabotropic glutamate receptor 5/μ-opioid receptor interaction was assessed by performing metabotropic glutamate receptor 5 autoradiographic binding in brains of mice lacking the μ-opioid receptor gene. Results: Withdrawal from chronic morphine administration induced anxiety-like, depressive-like, and impaired sociability behaviors concomitant with a marked upregulation of metabotropic glutamate receptor 5 binding. Administration of the metabotropic glutamate receptor 5 antagonist, 3-((2-Methyl-4-thiazolyl)ethynyl)pyridine, reversed morphine abstinence-induced depressive-like behaviors. A brain region-specific increase in metabotropic glutamate receptor 5 binding was observed in the nucleus accumbens shell, thalamus, hypothalamus, and amygdala of μ-opioid receptor knockout mice compared with controls. Conclusions: These results suggest an association between metabotropic glutamate receptor 5 alterations and the emergence of opioid withdrawal-related affective behaviors. This study supports metabotropic glutamate receptor 5 system as a target for the development of pharmacotherapies for the treatment of opioid addiction. Moreover, our data show direct effects of μ-opioid receptor system manipulation on metabotropic glutamate receptor 5 binding in the brain. PMID:26861145

Activators of potassium M currents have anticonvulsant actions in two rat models of encephalitis

PubMed Central

Solbrig, Marylou V.; Adrian, Russell; Wechsler, Steven L.; Koob, George F.

2010-01-01

Opioid systems in hippocampus regulate excitability and kappa opioids have a role in anticonvulsant protection, but their mechanisms of action are incompletely understood. We examined the ability of opioid and nonopioid agents with overlapping ionic mechanisms and actions similar to kappa opioid agonists, to block seizures in rat models of encephalitis due to Borna Disease virus and Herpes Simplex Virus Type-1. Naltrindole, a delta antagonist and thus a kappa opioid sparing agent, (10 mg/kg s.c.) blocked spontaneous and naloxone (opioid antagonist)-induced seizures in the models, but produced somatic signs similar to opioid withdrawal. Given that delta antagonists as well as kappa opioid agonists in hippocampus enhance potassium M currents (IM), we tested the effect of the IM augmenter flupirtine. Flupirtine (20 mg/kg i.p.) prevented seizures in Borna and herpes infected rats, without signs of withdrawal, hypotonia or sedation. The results support the efficacy of opioid and nonopioid drugs in modulating naloxone-induced seizures in critical illness due to viral encephalitis and by analogy, opioid withdrawal seizures. PMID:17126318

[Interindividual variation of pharmacokinetic disposition of and clinical responses to opioid analgesics in cancer pain patients].

PubMed

Naito, Takafumi; Kawakami, Junichi

2015-01-01

Use of prescription opioids for cancer pain according to the World Health Organization analgesic ladder has been accepted in Japan. Although oxycodone and fentanyl are commonly used as first-line analgesics, a few clinical reports have been published on interindividual variations in their pharmacokinetics and clinical responses in cancer patients. (1) Some factors relating to CYP2D6, CYP3A, ATP-binding cassette sub-family B member 1 (ABCB1), and opioid receptor mu 1 (OPRM1) involve oxycodone pharmacokinetics and sensitivity in humans. The relations between their genetic variations and clinical responses to oxycodone are being revealed in limited groups. In our study, the impact of genetic variants and pharmacokinetics on clinical responses to oxycodone were evaluated in Japanese populations. (2) Opioid switching improves the opioid tolerance related to the balance between analgesia and adverse effects. Some patients have difficulty in obtaining better opioid tolerance in recommended conversion ratios. The activities of CYP3A, ABCB1, and OPRM1 contribute to the interindividual variations in clinical responses to fentanyl in cancer patients. However, the variations in opioid switching remain to be clarified in clinical settings. In our study, genetic factors related to interindividual variations in clinical responses in opioid switching to fentanyl were revealed in Japanese populations. In this symposium review, the possibility of approaches to personalized palliative care using opioids based on genetic variants of CYP2D6, CYP3A5, ABCB1, and OPRM1 is discussed.

Morphine sulfate and naltrexone hydrochloride extended-release capsules: naltrexone release, pharmacodynamics, and tolerability.

PubMed

Johnson, Franklin; Setnik, Beatrice

2011-01-01

Morphine sulfate and naltrexone hydrochloride extended-release capsules (EMBEDA, King Pharmaceuticals, Inc., Bristol, TN), indicated for management of chronic, moderate-to-severe pain, contain pellets of extended-release morphine sulfate with a sequestered naltrexone core (MS-sNT). Taken as directed, morphine provides analgesia while naltrexone remains sequestered; if tampered with by crushing, naltrexone is released to mitigate morphine-induced euphoric effects. While it is necessary to establish that formulations intended to reduce attractiveness for abuse are successful in doing so, it is also necessary to demonstrate that product therapeutic integrity is maintained for patients. Data were reviewed from 3 studies to determine: 1) the quantity of naltrexone released when MS-sNT pellets are crushed (MS-sNTC) for at least 2 minutes with mortar and pestle); 2) the extent to which the naltrexone released upon crushing mitigated morphine-induced subjective effects; and 3) whether sequestered naltrexone precipitates opioid withdrawal when MS-sNT is taken as directed. The naltrexone bioavailability study compared naltrexone release from MS-sNTC with that from whole intact MS-sNT capsules (MS-sNTW) and an equal naltrexone solution (NS) dose. Equivalent bioavailability was established if 90% confidence intervals (CIs) for geometric mean ratios (maximum plasma naltrexone concentration [Cmax] and area under the concentration-time curve extrapolated to infinity [AUC∞]) fell between 80% and 125%. The oral pharmacodynamic study assessed drug liking and euphoria and pharmacokinetic properties of MS-sNTC and MS-sNTW compared with morphine sulfate solution (MSS) and placebo. The 12-month, open-label (OL) safety study evaluated safety of MS-sNT administered orally as directed in patients with chronic, moderate-to-severe pain. Safety assessments included withdrawal symptoms based on the Clinical Opiate Withdrawal Scale (COWS). Naltrexone from MS-sNTC met criteria for equivalent bioavailability to NS. Although morphine relative bioavailability was similar for MS-sNTC and MSS, mean peak (Emax) visual analog scale (VAS) scores for drug liking and Cole/Addiction Research Center Inventory Stimulation-Euphoria were significantly reduced for MS-sNTC vs MSS (p < 0.001). In these 2 studies, a total of 6 participants had one measurement of plasma naltrexone after MS-sNTW that was above the lower limit of quantification. In the OL safety study, 72/93 participants (77%) had no quantifiable naltrexone concentrations. There was neither evidence of naltrexone accumulation for any participant nor any significant correlation with MS-sNT dose, age, or sex. Of 4 participants with the highest naltrexone concentrations, none had COWS scores consistent with moderate opioid withdrawal symptoms. Only 5 participants had COWS scores consistent with moderate opioid withdrawal; all 5 had not taken MS-sNT as directed. Study populations may not be fully representative of patients receiving opioid therapy for the management of chronic, moderate-to-severe pain and of opioid abusers. When MS-sNT capsules are crushed, all of the sequestered naltrexone (relative to oral NS) is released and immediately available to mitigate morphine-induced effects. When MS-sNT was crushed, the naltrexone released abated drug liking and euphoria relative to that from an equal dose of immediate-release morphine from MSS administration in a majority of participants. Naltrexone concentrations were low over a period of 12 months without evidence of accumulation, and there were no observable opioid withdrawal symptoms when MS-sNT was taken as directed.

Activation of Peripheral κ-Opioid Receptors Normalizes Caffeine Effects Modified in Nicotine-Dependent Rats during Nicotine Withdrawal.

PubMed

Sudakov, S K; Bogdanova, N G

2016-10-01

The study examined the effect of peripheral (intragastric) ICI-204,448, an agonist of gastric κ-opioid receptors, on the psychostimulating and anxiolytic effects of caffeine in nicotinedependent rats at the stage of nicotine withdrawal. In these rats, the effects of caffeine (10 mg/kg) were perverted. In nicotine-dependent rats, caffeine produced an anxiolytic effect accompanied by pronounced stimulation of motor activity, in contrast to anxiogenic effect induced by caffeine in intact rats without nicotine dependence. During nicotine withdrawal, nicotine-dependent rats demonstrated enhanced sensitivity to nicotine. Intragastric administration of κ-opioid receptor agonist ICI-204,448 normalized the effect of caffeine in nicotinedependent rats. We have previously demonstrated that activation of peripheral κ-opioid receptors inhibited central κ-opioid activity and eliminated manifestations of nicotine withdrawal syndrome in nicotine-dependent rats, e.g. metabolism activation, stimulation of motor activity, and enhancement of food consumption. In its turn, inhibition of central κ-opioid structures activates the brain adenosine system, which can attenuate the caffeine-induced effects in nicotine-dependent rats.

Methadone Management of Withdrawal Associated With Loperamide-related Opioid Use Disorder.

PubMed

Leo, Raphael J; Ghazi, Muhammad A; Jaziri, Kelly S

: Loperamide hydrochloride is an over-the-counter anti-diarrheal agent, acting via mu-opioid receptor agonist effects in the intestinal myenteric plexus. Although preclinical investigations suggested that abuse liability associated with loperamide use is low, there are increasing numbers of cases reported to the US Food and Drug Administration, of abuse, dependence, and withdrawal associated with loperamide use. A case of a patient with opioid use disorder, that is, in the form of protracted loperamide excess use, requiring management of withdrawal with methadone is presented. Management of withdrawal from abrupt loperamide discontinuation has not been discussed in the literature. Long-term treatment issues are also described.

Problem drinking and low-dose naltrexone-assisted opioid detoxification.

PubMed

Mannelli, Paolo; Peindl, Kathleen; Patkar, Ashwin A; Wu, Li-Tzy; Tharwani, Haresh M; Gorelick, David A

2011-05-01

The influence of alcohol use on opioid dependence is a major problem that warrants a search for more effective treatment strategies. The addition of very-low-dose naltrexone (VLNTX) to methadone taper was recently associated with reduced withdrawal intensity during detoxification. In a secondary analysis of these data, we sought to determine whether problem drinking affects detoxification outcomes and whether symptoms are influenced by VLNTX use. Opioid-dependent patients (N = 174) received naltrexone (0.125 or 0.250 mg/day) or placebo in a double-blind, randomized design during methadone-based, 6-day inpatient detoxification. Alcohol consumption was assessed at admission using the Addiction Severity Index and selfreport. Outcome measures were opioid withdrawal intensity, craving, and retention in treatment. Problem drinking-opioid dependent patients (n = 79) showed episodic heavy alcohol use and reported increased subjective opioid withdrawal intensity (p = .001), craving (p = .001), and significantly lower rate of retention in treatment (p = .02). Individuals with problem drinking and opioid dependence who were treated with VLNTX (n = 55) showed reduced withdrawal (p = .05) and a lower rate of treatment discontinuation (p = .03), resuming alcohol intake in smaller numbers the day following discharge (p = .03). Treatment effects were more pronounced on anxiety, perspiration, shakiness, nausea, stomach cramps, and craving. There were no group differences in use of adjuvant medications and no treatment-related adverse events. Heavy drinking is associated with worse opioid detoxification outcomes. The addition of VLNTX is safe and is associated with reduced withdrawal symptoms and better completion rate in these patients. Further studies should explore the use of VLNTX in detoxification and long-term treatment of combined alcohol-opioid dependence and alcohol dependence alone.

Drug-induced GABA transporter currents enhance GABA release to induce opioid withdrawal behaviors.

PubMed

Bagley, Elena E; Hacker, Jennifer; Chefer, Vladimir I; Mallet, Christophe; McNally, Gavan P; Chieng, Billy C H; Perroud, Julie; Shippenberg, Toni S; Christie, MacDonald J

2011-10-30

Neurotransmitter transporters can affect neuronal excitability indirectly via modulation of neurotransmitter concentrations or directly via transporter currents. A physiological or pathophysiological role for transporter currents has not been described. We found that GABA transporter 1 (GAT-1) cation currents directly increased GABAergic neuronal excitability and synaptic GABA release in the periaqueductal gray (PAG) during opioid withdrawal in rodents. In contrast, GAT-1 did not indirectly alter GABA receptor responses via modulation of extracellular GABA concentrations. Notably, we found that GAT-1-induced increases in GABAergic activity contributed to many PAG-mediated signs of opioid withdrawal. Together, these data support the hypothesis that GAT-1 activity directly produces opioid withdrawal signs through direct hyperexcitation of GABAergic PAG neurons and nerve terminals, which presumably enhances GABAergic inhibition of PAG output neurons. These data provide, to the best of our knowledge, the first evidence that dysregulation of a neurotransmitter transporter current is important for the maladaptive plasticity that underlies opiate withdrawal.

Neonatal opioid withdrawal and antenatal opioid prescribing

PubMed Central

Gomes, Tara; Camacho, Ximena; Yao, Zhan; Guttmann, Astrid; Mamdani, Muhammad M.; Juurlink, David N.; Dhalla, Irfan A.

2015-01-01

Background The incidence of neonatal opioid withdrawal is increasing in both Canada and the United States. However, the degree to which the treatment of pain with opioids, rather than the misuse of prescription opioids or heroin, contributes to the prevalence of neonatal opioid withdrawal remains unknown. Methods We conducted a retrospective, population-based, cross-sectional study between 1992 and 2011 in Ontario with 2 objectives. First, we determined the annual incidence of neonatal abstinence syndrome. Second, using data from a subset of women eligible for publicly funded prescription drugs, we determined what proportion of women who deliver an infant with neonatal abstinence syndrome were given a prescription for an opioid before and during pregnancy. Results The incidence of neonatal abstinence syndrome in Ontario increased 15-fold during the study period, from 0.28 per 1000 live births in 1992 to 4.29 per 1000 live births in 2011. During the final 5 years of the study, we identified 927 deliveries of infants with neonatal abstinence syndrome to mothers who were public drug plan beneficiaries. Of these mothers, 67% had received an opioid prescription in the 100 days preceding delivery, including 53.3% who received methadone, an increase from 28.6% in the interval spanning 1 to 2 years before delivery (p < 0.001). Prescription for nonmethadone opioids decreased from 38% to 17% (p < 0.001). Interpretation The incidence of neonatal opioid withdrawal in Ontario has increased substantially over the last 20 years. Most of the women in this cohort who delivered an infant with neonatal abstinence syndrome had received a prescription for an opioid both before and during their pregnancy. PMID:25844370

Dextromethorphan and Quinidine Combination for Heroin Detoxification

PubMed Central

Akerele, Evaristo; Bisaga, Adam; Sullivan, Maria A.; Garawi, Fatima; Comer, Sandra D.; Thomas, Anil A.; Nunes, Edward V.; Kleber, Herbert D.

2015-01-01

Dextromethorphan (DM) is a low-affinity, non-competitive NMDA receptor antagonist that has shown promise in pre-clinical and preliminary clinical studies for the reduction of opioid withdrawal symptoms, but when used at higher doses, it is associated with deleterious side effects attributed to its metabolite, dextrorphan. A clinical trial was therefore conducted to test the withdrawal-suppressant effect of a combination of dextromethorphan with quinidine (DM/Q). Quinidine inhibits the metabolism of dextromethorphan, reducing dextrorphan levels. Opioid-dependent patients were admitted to an inpatient unit, stabilized for three days on morphine (25 mg, sc, every six hours), and randomly assigned on day 2 to DM/Q (30 mg/30 mg, twice a day) (n = 22) or matching placebo (n = 9) prior to the discontinuation of morphine on day 4. Withdrawal symptoms, measured with the Modified Himmelsbach Opioid Withdrawal Scale (MHOWS), increased significantly on days 4 and 5 (Z = 3.70, p = .0002), and by day 6, 90% of the sample (28/31) had dropped out of the study. There were no differences between treatment groups on either outcome measure. The combination of dextromethorphan and quinidine appears ineffective as a primary treatment for opioid withdrawal. Future studies should examine dextromethorphan as an adjunct to other anti-withdrawal medications and focus more on the relationship between dextrorphan levels and withdrawal suppression. PMID:18463993

On subclasses of opioid analgesics.

PubMed

Raffa, Robert B

2014-12-01

The history of discovery of analgesic drugs has followed a trajectory from original serendipitous discovery of plant-derived substances to laboratory creation of customized molecules that are intentionally designed to interact with specific receptors of neurotransmitters involved in either the transmission of the pain signal or the attenuation of such a signal. The drugs most recently developed have been designed to provide incremental greater separation between pain relief and adverse effects. The result has been drugs that have individualized pharmacodynamic and pharmacokinetic characteristics that represent specific advances in basic science and translate into unique clinical profiles. Several of the drugs include non-opioid components. They retain some of the features of opioids, but have distinct clinical characteristics that differentiate them from traditional opioids. Thus they defy simple classification as opioids. A summary is provided of the development of the modern view of multi-mechanistic pain and its treatment using analgesics that have multi-mechanisms of action (consisting of both opioid and non-opioid components). Descriptions of examples of such current analgesics and of those that have pharmacokinetic characteristics that result in atypical opioid clinical profiles are given. By serendipity or design, several current strong analgesics have opioid components of action, but have an additional non-opioid mechanism of action or some pharmacokinetic feature that gives them an atypical opioid clinical profile and renders them not easily classified as classical opioids. An appreciation that there are now opioid analgesics that differentiate from classical opioids in ways that defy their simplistic classification as opioids suggests that recognition of subclasses of opioid analgesics would be more accurate scientifically and would be more informative for healthcare providers and regulators. This would likely lead to positive outcomes for the clinical use and regulatory control of the current drugs, and provide direction/strategy for the discovery of new drugs.

Baclofen for maintenance treatment of opioid dependence: A randomized double-blind placebo-controlled clinical trial [ISRCTN32121581

PubMed Central

Assadi, Seyed Mohammad; Radgoodarzi, Reza; Ahmadi-Abhari, Seyed Ali

2003-01-01

Background Results of preclinical studies suggest that the GABAB receptor agonist baclofen may be useful in treatment of opioid dependence. This study was aimed at assessing the possible efficacy of baclofen for maintenance treatment of opioid dependence. Methods A total of 40 opioid-dependent patients were detoxified and randomly assigned to receive baclofen (60 mg/day) or placebo in a 12-week, double blind, parallel-group trial. Primary outcome measure was retention in treatment. Secondary outcome measures included opioids and alcohol use according to urinalysis and self-report ratings, intensity of opioid craving assessed with a visual analogue scale, opioid withdrawal symptoms as measured by the Short Opiate Withdrawal Scale and depression scores on the Hamilton inventory. Results Treatment retention was significantly higher in the baclofen group. Baclofen also showed a significant superiority over placebo in terms of opiate withdrawal syndrome and depressive symptoms. Non-significant, but generally favorable responses were seen in the baclofen group with other outcome measures including intensity of opioid craving and self-reported opioid and alcohol use. However, no significant difference was seen in the rates of opioid-positive urine tests. Additionally, the drug side effects of the two groups were not significantly different. Conclusion The results support further study of baclofen in the maintenance treatment of opioid dependence. PMID:14624703

Ethical and Human Rights Imperatives to Ensure Medication-Assisted Treatment for Opioid Dependence in Prisons and Pre-trial Detention

PubMed Central

Bruce, R. Douglas; Schleifer, Rebecca A.

2008-01-01

Opioid dependence is a complex medical condition affecting neurocognitive and physical functioning. Forced or abrupt opioid withdrawal may cause profound physical and psychological suffering, including nausea, vomiting, diarrhea, extreme agitation and/or anxiety. Opioid dependent individuals are especially vulnerable at the time of arrest or initial detention, when they may, as a result of their chemical dependency, be coerced into providing incriminating testimony, or be driven to engage in risky behavior (such as sharing needles in detention) in order to avoid painful withdrawal symptoms Upon incarceration, many opioid dependent prisoners are forced to undergo abrupt opioid withdrawal (both from legally prescribed agonist therapy such as methadone as well as illicit opioids). Physical and psychological symptoms attendant to withdrawal may impair capacity to make informed legal decisions, and cause prisoners to risk HIV and other bloodborne diseases by sharing injection equipment. Although prisons must provide at least the standard of care to prisoners that is available in the general population, medication-assisted treatment, endorsed by international health and drug agencies as an integral part of HIV prevention and care strategies for opioid dependent drug users, is unavailable to most prisoners. Medication-assisted treatment is a well-studied and validated pharmacological therapy for the medical condition known as opioid dependence. The failure to ensure prisoner access to this medical therapy threatens fundamental human rights protections against cruel, inhuman or degrading treatment and rights to health and to life. It also poses serious ethical problems for health care providers, violating basic principles of beneficence and non-maleficence (i.e., do good/do no harm). Governments must take immediate action to ensure access to opioid substitution to prisoners to ensure fulfillment of ethical and human rights obligations. PMID:18226517

Ethical and human rights imperatives to ensure medication-assisted treatment for opioid dependence in prisons and pre-trial detention.

PubMed

Bruce, R Douglas; Schleifer, Rebecca A

2008-02-01

Opioid dependence is a complex medical condition affecting neurocognitive and physical functioning. Forced or abrupt opioid withdrawal may cause profound physical and psychological suffering, including nausea, vomiting, diarrhoea, extreme agitation and/or anxiety. Opioid-dependent individuals are especially vulnerable at the time of arrest or initial detention, when they may, as a result of their chemical dependency, be coerced into providing incriminating testimony, or be driven to engage in risky behaviour (such as sharing needles in detention) in order to avoid painful withdrawal symptoms. Upon incarceration, many opioid-dependent prisoners are forced to undergo abrupt opioid withdrawal (both from legally prescribed agonist therapy such as methadone as well as illicit opioids). Physical and psychological symptoms attendant to withdrawal may impair capacity to make informed legal decisions, and cause prisoners to risk HIV and other blood-borne diseases by sharing injection equipment. Although prisons must provide at least the standard of care to prisoners that is available in the general population, medication-assisted treatment, endorsed by international health and drug agencies as an integral part of HIV prevention and care strategies for opioid-dependent drug users, is unavailable to most prisoners. Medication-assisted treatment is a well-studied and validated pharmacological therapy for the medical condition known as opioid dependence. The failure to ensure prisoner access to this medical therapy threatens fundamental human rights protections against cruel, inhuman or degrading treatment and rights to health and to life. It also poses serious ethical problems for health care providers, violating basic principles of beneficence and non-maleficence (i.e., do good/do no harm). Governments must take immediate action to ensure access to opioid substitution to prisoners to ensure fulfilment of ethical and human rights obligations.

Opiate and opioid withdrawal

MedlinePlus

... opiate withdrawal; Oxycontin - opiate withdrawal; Hydrocodone - opiate withdrawal; Detox - opiates; Detoxification - opiates ... facilities set up to help people with detoxification (detox). In a regular hospital, if symptoms are severe. ...

Review of Opioid Pharmacogenetics and Considerations for Pain Management.

PubMed

Owusu Obeng, Aniwaa; Hamadeh, Issam; Smith, Michael

2017-09-01

Opioid analgesics are the standards of care for the treatment of moderate to severe nociceptive pain, particularly in the setting of cancer and surgery. Their analgesic properties mainly emanate from stimulation of the μ receptors, which are encoded by the OPRM1 gene. Hepatic metabolism represents the major route of elimination, which, for some opioids, namely codeine and tramadol, is necessary for their bioactivation into more potent analgesics. The highly polymorphic nature of the genes coding for phase I and phase II enzymes (pharmacokinetics genes) that are involved in the metabolism and bioactivation of opioids suggests a potential interindividual variation in their disposition and, most likely, response. In fact, such an association has been substantiated in several pharmacokinetic studies described in this review, in which drug exposure and/or metabolism differed significantly based on the presence of polymorphisms in these pharmacokinetics genes. Furthermore, in some studies, the observed variability in drug exposure translated into differences in the incidence of opioid-related adverse effects, particularly nausea, vomiting, constipation, and respiratory depression. Although the influence of polymorphisms in pharmacokinetics genes, as well as pharmacodynamics genes (OPRM1 and COMT) on response to opioids has been a subject of intense research, the results have been somehow conflicting, with some evidence insinuating for a potential role for OPRM1. The Clinical Pharmacogenetics Implementation Consortium guidelines provide CYP2D6-guided therapeutic recommendations to individualize treatment with tramadol and codeine. However, implementation guidelines for other opioids, which are more commonly used in real-world settings for pain management, are currently lacking. Hence, further studies are warranted to bridge this gap in our knowledge base and ultimately ascertain the role of pharmacogenetic markers as predictors of response to opioid analgesics. © 2017 Pharmacotherapy Publications, Inc.

Risk factors associated with iatrogenic opioid and benzodiazepine withdrawal in critically ill pediatric patients: a systematic review and conceptual model.

PubMed

Best, Kaitlin M; Boullata, Joseph I; Curley, Martha A Q

2015-02-01

Analgesia and sedation are common therapies in pediatric critical care, and rapid titration of these medications is associated with iatrogenic withdrawal syndrome. We performed a systematic review of the literature to identify all common and salient risk factors associated with iatrogenic withdrawal syndrome and build a conceptual model of iatrogenic withdrawal syndrome risk in critically ill pediatric patients. Multiple databases, including PubMed/Medline, EMBASE, CINAHL, and the Cochrane Central Registry of Clinical Trials, were searched using relevant terms from January 1, 1980, to August 1, 2014. Articles were included if they were published in English and discussed iatrogenic withdrawal syndrome following either opioid or benzodiazepine therapy in children in acute or intensive care settings. Articles were excluded if subjects were neonates born to opioid- or benzodiazepine-dependent mothers, children diagnosed as substance abusers, or subjects with cancer-related pain; if data about opioid or benzodiazepine treatment were not specified; or if primary data were not reported. In total, 1,395 articles were evaluated, 33 of which met the inclusion criteria. To facilitate analysis, all opioid and/or benzodiazepine doses were converted to morphine or midazolam equivalents, respectively. A table of evidence was developed for qualitative analysis of common themes, providing a framework for the construction of a conceptual model. The strongest risk factors associated with iatrogenic withdrawal syndrome include duration of therapy and cumulative dose. Additionally, evidence exists linking patient, process, and system factors in the development of iatrogenic withdrawal syndrome. Most articles were prospective observational or interventional studies. Given the state of existing evidence, well-designed prospective studies are required to better characterize iatrogenic withdrawal syndrome in critically ill pediatric patients. This review provides data to support the construction of a conceptual model of iatrogenic withdrawal syndrome risk that, if supported, could be useful in guiding future research.

Inpatient Opioid Withdrawal Management of Street Children and Adolescents Admitted to Child and Adolescent Psychiatric Ward: A Preliminary Case Series

PubMed Central

Firouzkouhi Moghadam, Mahboubeh; Hashemian, Seyed-Sepehr; Pishjoo, Masoud; Ghasemi, Sanaz; Hajebi, Ahmad; Noroozi, Alireza

2016-01-01

Background About 10 million children worldwide live or work on the street. International reports estimate the prevalence of substance use among street children to be between 25% - 90%, which is who were referredntal disorders and high-risk behaviors. Objectives The objective of this study was to report the outcomes of assisted withdrawal of opioid-dependent vulnerable children and adolescents who were referred to child and adolescent psychiatric ward of Ali Ebne Abitaleb hospital, an academic hospital in Zahedan city. Methods Clinical chart abstractions were performed on a convenience sample of 40 serial opioid-dependent street children and adolescents (mean age: 11.14 ± 3.6 years) who were referred to child and adolescent psychiatric ward of Ali Ebne Abitaleb treatment and research center from November 2014 to May 2015. The demographic data, drug use history, comorbid physical and psychiatric conditions, symptomatology of opioid withdrawal syndrome, pharmacotherapies and psychosocial services, length of hospital stay, and any adverse events were extracted from the patients’ files using a checklist developed by the authors. Results Twenty-four (60%) patients were male, and 16 (40%) were female. The main drug used by all patients was opioids. Heroin Kerack (which has a street name of crystal in southeast Iran) was the most common (75%) drug of use, followed by opium (10%) and opium residue (7.5%). None of the participants self-reported using injected drugs. The high rate of a lack of eligibility for guardianship was documented among parents (87.5%) mainly due to their use of illegal drugs. Musculoskeletal pain and diarrhea were the most common withdrawal symptoms of the patients upon admission. The mean length of stay was 10.8 (± 7.30) days, and no significant adverse events were reported during the symptomatic treatment of opioid withdrawal syndrome. Conclusions To our knowledge, this is the first study to report on the safety and feasibility of inpatient symptomatic pharmacological treatment for assisted withdrawal among opioid-dependent children and adolescents in Iran. More well-designed studies to investigate the long-term outcomes of opioid treatment among children are warranted. PMID:27729958

Supersensitive Kappa Opioid Receptors Promotes Ethanol Withdrawal-Related Behaviors and Reduce Dopamine Signaling in the Nucleus Accumbens.

PubMed

Rose, Jamie H; Karkhanis, Anushree N; Chen, Rong; Gioia, Dominic; Lopez, Marcelo F; Becker, Howard C; McCool, Brian A; Jones, Sara R

2016-05-01

Chronic ethanol exposure reduces dopamine transmission in the nucleus accumbens, which may contribute to the negative affective symptoms associated with ethanol withdrawal. Kappa opioid receptors have been implicated in withdrawal-induced excessive drinking and anxiety-like behaviors and are known to inhibit dopamine release in the nucleus accumbens. The effects of chronic ethanol exposure on kappa opioid receptor-mediated changes in dopamine transmission at the level of the dopamine terminal and withdrawal-related behaviors were examined. Five weeks of chronic intermittent ethanol exposure in male C57BL/6 mice were used to examine the role of kappa opioid receptors in chronic ethanol-induced increases in ethanol intake and marble burying, a measure of anxiety/compulsive-like behavior. Drinking and marble burying were evaluated before and after chronic intermittent ethanol exposure, with and without kappa opioid receptor blockade by nor-binaltorphimine (10mg/kg i.p.). Functional alterations in kappa opioid receptors were assessed using fast scan cyclic voltammetry in brain slices containing the nucleus accumbens. Chronic intermittent ethanol-exposed mice showed increased ethanol drinking and marble burying compared with controls, which was attenuated with kappa opioid receptor blockade. Chronic intermittent ethanol-induced increases in behavior were replicated with kappa opioid receptor activation in naïve mice. Fast scan cyclic voltammetry revealed that chronic intermittent ethanol reduced accumbal dopamine release and increased uptake rates, promoting a hypodopaminergic state of this region. Kappa opioid receptor activation with U50,488H concentration-dependently decreased dopamine release in both groups; however, this effect was greater in chronic intermittent ethanol-treated mice, indicating kappa opioid receptor supersensitivity in this group. These data suggest that the chronic intermittent ethanol-induced increase in ethanol intake and anxiety/compulsive-like behaviors may be driven by greater kappa opioid receptor sensitivity and a hypodopaminergic state of the nucleus accumbens. © The Author 2015. Published by Oxford University Press on behalf of CINP.

THE EFFECTS OF DRONABINOL DURING DETOXIFICATION AND THE INITIATION OF TREATMENT WITH EXTENDED RELEASE NALTREXONE

PubMed Central

Bisaga, Adam; Sullivan, Maria A.; Glass, Andrew; Mishlen, Kaitlyn; Pavlicova, Martina; Haney, Margaret; Raby, Wilfrid N.; Levin, Frances R.; Carpenter, Kenneth M.; Mariani, John J.; Nunes, Edward V.

2015-01-01

Background Evidence suggests that the cannabinoid system is involved in the maintenance of opioid dependence. We examined whether dronabinol, a cannabinoid receptor type 1 partial agonist, reduces opioid withdrawal and increases retention in treatment with extended release naltrexone (XR-naltrexone). Methods Opioid dependent participants were randomized to receive dronabinol 30 mg/d (n=40) or placebo (n=20), under double-blind conditions, while they underwent inpatient detoxification and naltrexone induction. Before discharge all participants received an injection of XR-naltrexone, with an additional dose given four weeks later. Dronabinol or placebo was given while inpatient and for 5 weeks afterwards. The primary outcomes were the severity of opioid withdrawal, measured with the Subjective Opioid Withdrawal Scale, and retention in treatment at the end of the inpatient phase and at the end of the 8-week trial. Results The severity of opioid withdrawal during inpatient phase was lower in the dronabinol group relative to placebo group (p=0.006). Rates of successful induction onto XR-naltrexone (dronabinol 66%, placebo 55%) and completion of treatment (dronabinol 35%, placebo 35%) were not significantly different. Post-hoc analysis showed that the 32% of participants who smoked marijuana regularly during the outpatient phase had significantly lower ratings of insomnia and anxiety and were more likely to complete the 8-week trial. Conclusion Dronabinol reduced the severity of opiate withdrawal during acute detoxification but had no effect on rates of XR-naltrexone treatment induction and retention. Participants who elected to smoke marijuana during the trial were more likely to complete treatment regardless of treatment group assignment. PMID:26187456

Opioid dependence and substitution therapy: thymoquinone as potential novel supplement therapy for better outcome for methadone maintenance therapy substitution therapy

PubMed Central

Adnan, Liyana Hazwani Mohd; Bakar, Nor Hidayah Abu; Mohamad, Nasir

2014-01-01

Methadone is widely being used for opioid substitution therapy. However, the administration of methadone to opioid dependent individual is frequently accompanied by withdrawal syndrome and chemical dependency develops. Other than that, it is also difficult to retain patients in the treatment programme making their retention rates are decreasing over time. This article is written to higlights the potential use of prophetic medicines, Nigella sativa, as a supplement for opioid dependent receiving methadone. It focuses on the potential role of N. sativa and its major active compound, Thymoquinone (TQ) as a calcium channel blocking agent to reduce withdrawal syndrome and opioid dependency. PMID:25859295

A double-blind, placebo-controlled trial of dextromethorphan combined with clonidine in the treatment of heroin withdrawal.

PubMed

Lin, Shih-Ku; Pan, Chun-Hung; Chen, Chia-Hui

2014-08-01

Dextromethorphan has been reported to ameliorate opioid withdrawal symptoms in both animal and human subjects. In the present study, we investigated the efficacy of dextromethorphan as an add-on medication in heroin detoxification treatment in a double-blind, placebo-controlled design. Sixty-five heroin-dependent patients (male, 63; female, 2) participated in this inpatient detoxification trial after giving informed consent. Clonidine 0.075 mg 4 times a day was given as an antiwithdrawal medication at baseline. Each patient was then randomly assigned to treatment with either dextromethorphan 60 mg or placebo 4 times a day as additional medication. Flurazepam 30 mg was given before bedtime for insomnia. Other medications that were allowed included loperamide for diarrhea and lorazepam for agitation. Participants were monitored using the Objective Opioid Withdrawal Scale 3 times a day as the primary outcome to compare drug efficacy between groups. Generalized estimating equation model analysis revealed that the Objective Opioid Withdrawal Scale had no group difference between dextromethorphan and placebo group overall (P = 0.29), whereas a significant difference between groups was found during day 3 to day 6 (P = 0.04) by post hoc analysis. There was no difference in the Clinical Global Impression Scale, patient's impression of treatment, and use of ancillary medications between groups. No severe adverse effects were noticed. We suggest that dextromethorphan has some beneficial effect in attenuating the severity of opioid withdrawal symptoms and can be used as an adjunction medication in the treatment of opioid withdrawal, whereas the exact efficacy needs further investigation.

Tobacco withdrawal among opioid-dependent smokers.

PubMed

Streck, Joanna M; Heil, Sarah H; Higgins, Stephen T; Bunn, Janice Y; Sigmon, Stacey C

2018-04-01

Prevalence of cigarette smoking among opioid-dependent individuals is 6-fold that of the general U.S. adult population and their quit rates are notoriously poor. One possible reason for the modest cessation outcomes in opioid-dependent smokers may be that they experience more severe tobacco withdrawal upon quitting. In this secondary analysis, we evaluated tobacco withdrawal in opioid-dependent (OD) smokers versus smokers without co-occurring substance use disorders (SUDs). Participants were 47 methadone- or buprenorphine-maintained smokers and 25 non-SUD smokers who completed 1 of several 2-week studies involving daily visits for biochemical monitoring, delivery of financial incentives contingent on smoking abstinence, and assessment of withdrawal via the Minnesota Nicotine Withdrawal Scale (MNWS). Prior to quitting smoking, OD smokers presented with higher baseline withdrawal scores than non-SUD smokers (1.7 ± 0.2 vs. 0.7 ± 0.2, respectively; F [1, 63] = 7.31, p < .001). Withdrawal scores in both groups decreased over the subsequent 2-week period with no group differences, F (1, 910) = 0.50, p = .48. A similar pattern was observed on craving (i.e., Desire to Smoke item of MNWS), although the trajectory of decrease over time on this item was also moderated by gender. Overall, there was no difference in withdrawal during biochemically verified smoking abstinence between OD and non-SUD smokers, suggesting that elevated withdrawal severity following quitting may not be a major factor contributing to the poor cessation outcomes consistently observed among OD smokers. Further scientific efforts are needed to improve our understanding of the high smoking rates and modest cessation outcomes in this challenging population. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Tapering off long-term opioid therapy in chronic non-cancer pain patients: a randomized clinical trial.

PubMed

Kurita, Geana Paula; Højsted, Jette; Sjøgren, Per

2018-05-13

The indications for initiating long-term opioid treatment (L-TOT) for chronic non-cancer pain (CNCP) are often unclear and associated with problematic use. This study aimed at evaluating the efficacy of stabilizing opioid therapy followed by a sequential opioid tapering off program in CNCP patients. A randomized clinical trial with a medications stabilization period (Phase 1) followed by a opioid tapering off program (Phase 2). In Phase 2, patients were randomized to Control Group (stable treatment) or Taper off Group (sequential opioid dose reduction) and assessed at baseline, after stabilization and up to six months. Primary outcomes: measures of cognitive function; secondary outcomes: pain, sleep, rest, quality of life, depression, anxiety, opioid misuse, and opioid withdrawal symptoms. Two hundred seventy-four patients were screened; 75 were included, out of which 40 dropped out before Phase 2. Those who succeeded Phase 1 (n=35) had weak/moderate improvements of psychomotor function (p=0.020), sleeping hours (p=0.031), opioid withdrawal symptoms (p=0.019), measures of quality of life (p≤0.043) and opioid misuse scores (p=0.003). In Phase 2, patients in Taper off Group (n=15) experienced stable pain intensity and felt significantly more rested at third assessment than the Control Group (n=20). The opioid tapering off program was not successful due to the vast number of dropouts. Phase 1 was associated with weak to moderate improvements on psychomotor function, sleeping, opioid withdrawal symptoms, quality of life, and reduced risk of opioid misuse. In the intervention group of Phase 2, pain intensity was stable and patients felt more rested. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Psychometric evaluation of the Dutch version of the Subjective Opiate Withdrawal Scale (SOWS).

PubMed

Dijkstra, Boukje A G; Krabbe, Paul F M; Riezebos, Truus G M; van der Staak, Cees P F; De Jong, Cor A J

2007-01-01

To evaluate the psychometric properties of the Dutch version of the 16-item Subjective Opiate Withdrawal Scale (SOWS). The SOWS measures withdrawal symptoms at the time of assessment. The Dutch SOWS was repeatedly administered to a sample of 272 opioid-dependent inpatients of four addiction treatment centers during rapid detoxification with or without general anesthesia. Examination of the psychometric properties of the SOWS included exploratory factor analysis, internal consistency, test-retest reliability, and criterion validity. Exploratory factor analysis of the SOWS revealed a general pattern of four factors with three items not always clustered in the same factors at different points of measurement. After excluding these items from factor analysis four factors were identified during detoxification (temperature dysregulation, tractus locomotorius, tractus gastro-intestinalis and facial disinhibition). The 13-item SOWS shows high internal consistency and test-retest reliability and good validity at different stages of withdrawal. The 13-item SOWS is a reliable and valid instrument to assess opioid withdrawal during rapid detoxification. Three items were deleted because their content does not correspond directly with opioid withdrawal symptoms. Copyright (c) 2007 S. Karger AG, Basel.

The effect of flavonol glycosides on opiate withdrawal.

PubMed

Capasso, Anna

2007-07-01

Our interest has been centered on flavonol glycosides from Croton Menthodorus (Euphorbiaceae) and Aristeguietia discolor (Asteraceae). In this respect, the effect of flavonol glycosides from Croton Menthodorus (Euphorbiaceae) and Aristeguietia discolor (Asteraceae) was investigated on the naloxone-precipitated withdrawal contracture of the acute morphine-dependent guinea-pig ileum in vitro. Furthermore, the effect of these flavonol glycosides was also considered on DAGO (highly selective micro-agonist) and U50-488H (highly selective k-agonist) withdrawal to test whether the possible interaction of flavonol glycosides on opioid withdrawal involves micro- and/or k-opioid receptors. Flavonol glycosides from Croton Menthodorus (1 x 10(-5), 5 x 10(-5) and 1 x 10(-4) M) and from Aristeguietia discolor (1 x 10(-7)-1 x 10(-6)-1 x 10(-5) M) before or after the opioid agonists were able to both prevent and reverse the naloxone-induced contracture after exposure to micro (morphine and DAGO) or k (U50-488H) opiate agonists in a concentration-dependent fashion. Both acetylcholine response and electrical stimulation were reduced by flavonol glycosides treatment as well as the final opiate withdrawal was still reduced. The results of the present study indicate that flavonol glycosides were able to produce significant influence on the opiate withdrawal in vitro and these compounds were able to exert their effects both at micro and k opioid agonists.

Early outcomes following low dose naltrexone enhancement of opioid detoxification.

PubMed

Mannelli, Paolo; Patkar, Ashwin A; Peindl, Kathleen; Gottheil, Edward; Wu, Li-Tzy; Gorelick, David A

2009-01-01

Although withdrawal severity and treatment completion are the initial focus of opioid detoxification, post-detoxification outcome better defines effective interventions. Very low dose naltrexone (VLNTX) in addition to methadone taper was recently associated with attenuated withdrawal intensity during detoxification. We describe the results of a seven-day follow-up evaluation of 96 subjects who completed inpatient detoxification consisting of the addition of VLNTX (0.125 or 0.250 mg per day) or placebo to methadone taper in a double blind, randomized investigation. Individuals receiving VLNTX during detoxification reported reduced withdrawal and drug use during the first 24 hours after discharge. VLNTX addition was also associated with higher rates of negative drug tests for opioids and cannabis and increased engagement in outpatient treatment after one week. Further studies are needed to test the utility of this approach in easing the transition from detoxification to various follow-up treatment modalities designed to address opioid dependence.

Comparison of efficacy between buprenorphine and tramadol in the detoxification of opioid (heroin)-dependent subjects.

PubMed

Chawla, Jatinder Mohan; Pal, Hemraj; Lal, Rakesh; Jain, Raka; Schooler, Nina; Balhara, Yatan Pal Singh

2013-01-01

Tramadol is a synthetic opiate and a centrally acting weak m-opioid receptor agonist. The potential advantages of tramadol include ease of administration, low abuse potential, and being nonscheduled. This study compared tramadol and buprenorphine for controlling withdrawal symptoms in patients with opioid dependence syndrome. Consenting male subjects between 20 and 45 years of age who fulfilled the ICD-10-DCR criteria for opiate dependence syndrome were randomly assigned in a double-blind, double-dummy placebo-controlled trial for detoxification. Those with multiple drug dependence, abnormal cardiac, renal and hepatic functions, psychosis, or organic mental illness were excluded. Assessments included Subjective Opiate Withdrawal Scale (SOWS), Objective Opiate Withdrawal Scale (OOWS), Visual Analog Scale (VAS), and Side Effect Check List. Subjects were evaluated daily and study duration was 10 days. Sixty two subjects were enrolled. The mean SOWS and OOWS and VAS were significantly lower in the buprenorphine group on second and third day of detoxification as compared to the tramadol group. Although the retention rate was higher for buprenorphine group throughout the study, when compared with tramadol the difference was not significant on any day. Three subjects in the tramadol group had seizures. Tramadol was found to have limited detoxification efficacy in moderate to severe opioid withdrawal and substantial risk of seizures as compared to buprenorphine. Further studies are warranted to examine its efficacy in mild opioid withdrawal symptoms and its potential use in outpatient settings where its administration advantages may be valuable.

Dextromethorphan differentially affects opioid antinociception in rats

PubMed Central

Chen, Shiou-Lan; Huang, Eagle Yi-Kung; Chow, Lok-Hi; Tao, Pao-Luh

2005-01-01

Opioid drugs such as morphine and meperidine are widely used in clinical pain management, although they can cause some adverse effects. A number of studies indicate that N-methyl-D-aspartate (NMDA) receptors may play a role in the mechanism of morphine analgesia, tolerance and dependence. Being an antitussive with NMDA antagonist properties, dextromethorphan (DM) may have some therapeutic benefits when coadministered with morphine. In the present study, we investigated the effects of DM on the antinociceptive effects of different opioids. We also investigated the possible pharmacokinetic mechanisms involved. The antinociceptive effects of the μ-opioid receptor agonists morphine (5 mg kg−1, s.c.), meperidine (25 mg kg−1, s.c.) and codeine (25 mg kg−1, s.c.), and the κ-opioid agonists nalbuphine (8 mg kg−1, s.c.) and U-50,488H (20 mg kg−1, s.c.) were studied using the tail-flick test in male Sprague–Dawley rats. Coadministration of DM (20 mg kg−1, i.p.) with these opioids was also performed and investigated. The pharmacokinetic effects of DM on morphine and codeine were examined, and the free concentration of morphine or codeine in serum was determined by HPLC. It was found that DM potentiated the antinociceptive effects of some μ-opioid agonists but not codeine or κ-opioid agonists in rats. DM potentiated morphine's antinociceptive effect, and acutely increased the serum concentration of morphine. In contrast, DM attenuated the antinociceptive effect of codeine and decreased the serum concentration of its active metabolite (morphine). The pharmacokinetic interactions between DM and opioids may partially explain the differential effects of DM on the antinociception caused by opioids. PMID:15655510

Effects of Daily Morphine Administration and Deprivation on Choice and Demand for Remifentanil and Cocaine in Rhesus Monkeys

ERIC Educational Resources Information Center

Wade-Galuska, Tammy; Galuska, Chad M.; Winger, Gail

2011-01-01

Choice procedures have indicated that the relative reinforcing effectiveness of opioid drugs increases during opioid withdrawal. The demand curve, an absolute measure of reinforcer value, has not been applied to this question. The present study assessed whether mild morphine withdrawal would increase demand for or choice of remifentanil or…

Opioids and Chronic Pain | NIH MedlinePlus the Magazine

MedlinePlus

... term daily use of opioids leads to physical dependence, which is not to be confused with addiction ... screened and closely monitored. When people have physical dependence and the opioid use is stopped, withdrawal symptoms ...

Blockade of Endocannabinoid Hydrolytic Enzymes Attenuates Precipitated Opioid Withdrawal Symptoms in MiceS⃞

PubMed Central

Ramesh, Divya; Ross, Gracious R.; Schlosburg, Joel E.; Owens, Robert A.; Abdullah, Rehab A.; Kinsey, Steven G.; Long, Jonathan Z.; Nomura, Daniel K.; Sim-Selley, Laura J.; Cravatt, Benjamin F.; Akbarali, Hamid I.

2011-01-01

Δ9-Tetrahydrocannbinol (THC), the primary active constituent of Cannabis sativa, has long been known to reduce opioid withdrawal symptoms. Although THC produces most of its pharmacological actions through the activation of CB1 and CB2 cannabinoid receptors, the role these receptors play in reducing the variety of opioid withdrawal symptoms remains unknown. The endogenous cannabinoids, N-arachidonoylethanolamine (anandamide; AEA) and 2-arachidonylglycerol (2-AG), activate both cannabinoid receptors but are rapidly metabolized by fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), respectively. The objective of this study was to test whether increasing AEA or 2-AG, via inhibition of their respective hydrolytic enzymes, reduces naloxone-precipitated morphine withdrawal symptoms in in vivo and in vitro models of opioid dependence. Morphine-dependent mice challenged with naloxone reliably displayed a profound withdrawal syndrome, consisting of jumping, paw tremors, diarrhea, and weight loss. THC and the MAGL inhibitor 4-nitrophenyl 4-(dibenzo[d][1,3]dioxol-5-yl(hydroxy)methyl)piperidine-1-carboxylate (JZL184) dose dependently reduced the intensity of most measures through the activation of CB1 receptors. JZL184 also attenuated spontaneous withdrawal signs in morphine-dependent mice. The FAAH inhibitor N-(pyridin-3-yl)-4-(3-(5-(trifluoromethyl)pyridin-2-yloxy)benzyl)-piperdine-1-carboxamide (PF-3845) reduced the intensity of naloxone-precipitated jumps and paw flutters through the activation of CB1 receptors but did not ameliorate incidence of diarrhea or weight loss. In the final series of experiments, we investigated whether JZL184 or PF-3845 would attenuate naloxone-precipitated contractions in morphine-dependent ilea. Both enzyme inhibitors attenuated the intensity of naloxone-induced contractions, although this model does not account mechanistically for the autonomic withdrawal responses (i.e., diarrhea) observed in vivo. These results indicate that endocannabinoid catabolic enzymes are promising targets to treat opioid dependence. PMID:21719468

DOE Office of Scientific and Technical Information (OSTI.GOV)

Navarro-Zaragoza, J.; Martínez-Laorden, E.; Mora, L.

Opioid addiction is associated with cardiovascular disease. However, mechanisms linking opioid addiction and cardiovascular disease remain unclear. This study investigated the role of corticotropin-releasing factor (CRF) 1 receptor in mediating somatic signs and the behavioural states produced during withdrawal from morphine dependence. Furthermore, it studied the efficacy of CRF1 receptor antagonist, CP-154,526 to prevent the cardiac sympathetic activity induced by morphine withdrawal. In addition, tyrosine hydroxylase (TH) phosphorylation pathways were evaluated. Like stress, morphine withdrawal induced an increase in the hypothalamic–pituitary–adrenal (HPA) axis activity and an enhancement of noradrenaline (NA) turnover. Pre-treatment with CRF1 receptor antagonist significantly reduced morphine withdrawal-inducedmore » increases in plasma adrenocorticotropic hormone (ACTH) levels, NA turnover and TH phosphorylation at Ser31 in the right ventricle. In addition, CP-154,526 reduced the phosphorylation of extracellular signal-regulated kinase (ERK) after naloxone-precipitated morphine withdrawal. In addition, CP-154,526 attenuated the increases in body weight loss during morphine treatment and suppressed some of morphine withdrawal signs. Altogether, these results support the idea that cardiac sympathetic pathways are activated in response to naloxone-precipitated morphine withdrawal suggesting that treatment with a CRF1 receptor antagonist before morphine withdrawal would prevent the development of stress-induced behavioural and autonomic dysfunction in opioid addicts. - Highlights: • Morphine withdrawal caused an increase in myocardial sympathetic activity. • ERK regulates TH phosphorylation after naloxone-induced morphine withdrawal. • CRF1R is involved in cardiac adaptive changes during morphine dependence.« less

Severity of Withdrawal Symptoms, Plasma Oxytocin Levels, and Treatment Outcome in Heroin Users Undergoing Acute Withdrawal.

PubMed

Nikolaou, Kakia; Kapoukranidou, Dorothea; Ndungu, Samuel; Floros, Georgios; Kovatsi, Leda

2017-01-01

Pre-clinical studies show that, following chronic opioid exposure, oxytocin neurons exhibit over-excitation upon withdrawal, causing an increase in oxytocin brain and plasma levels. Relevant clinical data on humans are scarce. This study investigates the opioid withdrawal stress effect on oxytocin plasma levels in humans. We evaluated 57 male chronic heroin users in a residential detoxification program. We determined plasma oxytocin levels by ELISA and measured the stress effects of withdrawal using the COWS scale for opioid withdrawal, the VAS scale for craving, and the Hamilton scales for anxiety and depression on the second day of admission. Out of the 57 patients enrolled in the study, 27 completed the 21-day program, while the remaining 30 dropped out prior to completion. Plasma oxytocin levels were significantly higher in those individuals who dropped out than in those who completed the program. Participants who dropped out at some stage scored higher in the COWS, VAS-Craving, and Hamilton-anxiety scales, indicating a higher stress and explaining the higher oxytocin levels. In addition, plasma oxytocin levels correlated positively with the scores achieved in the COWS and Hamilton-anxiety scales. Higher withdrawal stress levels are associated with higher plasma oxytocin levels and early treatment discharge.

Endogenous opioid system: a promising target for future smoking cessation medications.

PubMed

Norman, Haval; D'Souza, Manoranjan S

2017-05-01

Nicotine addiction continues to be a health challenge across the world. Despite several approved medications, smokers continue to relapse. Several human and animal studies have evaluated the role of the endogenous opioid system as a potential target for smoking cessation medications. In this review, studies that have elucidated the role of the mu (MORs), delta (DORs), and kappa (KORs) opioid receptors in nicotine reward, nicotine withdrawal, and reinstatement of nicotine seeking will be discussed. Additionally, the review will discuss discrepancies in the literature and therapeutic potential of the endogenous opioid system, and suggest studies to address gaps in knowledge with respect to the role of the opioid receptors in nicotine dependence. Data available till date suggest that blockade of the MORs and DORs decreased the rewarding effects of nicotine, while activation of the MORs and DORs decreased nicotine withdrawal-induced aversive effects. In contrast, activation of the KORs decreased the rewarding effects of nicotine, while blockade of the KORs decreased nicotine withdrawal-induced aversive effects. Interestingly, blockade of the MORs and KORs attenuated reinstatement of nicotine seeking. In humans, MOR antagonists have shown benefits in select subpopulations of smokers and further investigation is required to realize their full therapeutic potential. Future work must assess the influence of polymorphisms in opioid receptor-linked genes in nicotine dependence, which will help in both identifying individuals vulnerable to nicotine addiction and the development of opioid-based smoking cessation medications. Overall, the endogenous opioid system continues to be a promising target for future smoking cessation medications.

Drug interactions: volatile anesthetics and opioids.

PubMed

Glass, P S; Gan, T J; Howell, S; Ginsberg, B

1997-09-01

Multiple drugs are used to provide anesthesia. Volatile anesthetics are commonly combined with opioids. Several studies have demonstrated that small doses of opioid (i.e., within the analgesic range) result in a marked reduction in minimum alveolar concentration (MAC) of the volatile anesthetic that will prevent purposeful movement in 50% of patients at skin incision). Further increases in opioid dose provide only a further small reduction in MAC. Thus, a ceiling effect of the opioid is observed at a MAC value of the volatile anesthetic equal to its MAC awake. Recovery from anesthesia when an opioid is combined with a volatile anesthetic is dependent on the rate of decrease of both drugs to their respective concentrations that are associated with adequate spontaneous ventilation and awakening. Through an understanding of the pharmacodynamic interaction of volatile anesthetics with opioids and the pharmacokinetic processes responsible for the recovery from drug effect, optimal dosing schemes can thus be developed. A review of these pharmacodynamic and pharmacokinetic principles that will allow clinicians to administer drugs to provide a more optimal anesthetic is provided.

Deficiency in the Opioid Hypotheses of Self-Injurious Behavior.

ERIC Educational Resources Information Center

King, Bryan H.; And Others

1991-01-01

This commentary critiques two papers by Curt Sandman, pointing out interpretive problems in models explaining self-injurious behavior in terms of opioids. Withdrawal effects are emphasized as an alternative to hypotheses asserting congenital opioid excess as a cause of sensory depression or an addiction to a relative excess of opioid activity in…

Depression of home cage wheel running is an objective measure of spontaneous morphine withdrawal in rats with and without persistent pain

PubMed Central

Kandasamy, Ram; Lee, Andrea T.; Morgan, Michael M.

2017-01-01

Opioid withdrawal in humans is often subtle and almost always spontaneous. In contrast, most preclinical studies precipitate withdrawal by administration of an opioid receptor antagonist such as naloxone. These animal studies rely on measurement of physiological symptoms (e.g., wet dog shakes) in the period immediately following naloxone administration. To more closely model the human condition, we tested the hypothesis that depression of home cage wheel running will provide an objective method to measure the magnitude and duration of spontaneous morphine withdrawal. Rats were allowed access to a running wheel in their home cage for 8 days prior to implantation of two 75 mg morphine or placebo pellets. The pellets were removed 3 or 5 days later to induce spontaneous withdrawal. In normal pain-free rats, removal of the morphine pellets depressed wheel running for 48 hours compared to rats that had placebo pellets removed. Morphine withdrawal-induced depression of wheel running was greatly enhanced in rats with persistent inflammatory pain induced by injection of Complete Freund’s Adjuvant (CFA) into the hindpaw. Removal of the morphine pellets following 3 days of treatment depressed wheel running in these rats for over 6 days. These data demonstrate that home cage wheel running provides an objective and more clinically relevant method to assess spontaneous morphine withdrawal compared to precipitated withdrawal in laboratory rats. Moreover, the enhanced withdrawal in rats with persistent inflammatory pain suggests that pain patients may be especially susceptible to opioid withdrawal. PMID:28366799

Opioid pharmaceuticals and addiction: the issues, and research directions seeking solutions.

PubMed

Walwyn, Wendy M; Miotto, Karen A; Evans, Christopher J

2010-05-01

There are few pharmaceuticals superior to opiates for the treatment of pain. However, with concerns of addiction, withdrawal and questionable efficacy for all types of pain, these compounds are far from a magical panacea for pain-relief. As it is unlikely that other classes of compounds will supersede the opioids in the very near future, it is important to both optimize current opioid therapies and curb the astounding diversion of opioids from their intended analgesic use to non-medical abuse. In optimizing opioid therapeutics it is necessary to enhance the clinical awareness of the benefits of treating pain and combine this with aggressive strategies to reduce diversion for non-medical use. At the heart of the issue of opioid misuse is the role of opioid systems in the reward circuitry, and the adaptive processes associated with repetitive opioid use that manifest during withdrawal. Emerging pharmacological insights of opioid receptors will be reviewed that provide future hope for developing opioid-based analgesics with reduced addictive properties and perhaps, reduced opponent processes. In addition, with the increased understanding of nociceptive circuitry and the molecules involved in transmitting pain, new therapeutic targets have become evident that may result in effective analgesics either alone or in combination with current opioid therapies.

Opioid pharmaceuticals and addiction: The issues, and research directions seeking solutions

PubMed Central

Walwyn, Wendy M.; Miotto, Karen A.; Evans, Christopher J.

2011-01-01

There are few pharmaceuticals superior to opiates for the treatment of pain. However, with concerns of addiction, withdrawal and questionable efficacy for all types of pain, these compounds are far from a magical panacea for pain-relief. As it is unlikely that other classes of compounds will supersede the opioids in the very near future, it is important to both optimize current opioid therapies and curb the astounding diversion of opioids from their intended analgesic use to non-medical abuse. In optimizing opioid therapeutics it is necessary to enhance the clinical awareness of the benefits of treating pain and combine this with aggressive strategies to reduce diversion for non-medical use. At the heart of the issue of opioid misuse is the role of opioid systems in the reward circuitry, and the adaptive processes associated with repetitive opioid use that manifest during withdrawal. Emerging pharmacological insights of opioid receptors will be reviewed that provide future hope for developing opioid-based analgesics with reduced addictive properties and perhaps, reduced opponent processes. In addition, with the increased understanding of nociceptive circuitry and the molecules involved in transmitting pain, new therapeutic targets have become evident that may result in effective analgesics either alone or in combination with current opioid therapies. PMID:20188495

Sex Differences in Regional Brain Glucose Metabolism Following Opioid Withdrawal and Replacement.

PubMed

Santoro, Giovanni C; Carrion, Joseph; Patel, Krishna; Vilchez, Crystal; Veith, Jennifer; Brodie, Jonathan D; Dewey, Stephen L

2017-08-01

Methadone and buprenorphine are currently the most common pharmacological treatments for opioid dependence. Interestingly, the clinical response to these drugs appears to be sex specific. That is, females exhibit superior therapeutic efficacy, defined as extended periods of abstinence and longer time to relapse, compared with males. However, the underlying metabolic effects of opioid withdrawal and replacement have not been examined. Therefore, using 18 FDG and microPET, we measured differences in regional brain glucose metabolism in males and females following morphine withdrawal and subsequent methadone or buprenorphine replacement. In both males and females, spontaneous opioid withdrawal altered glucose metabolism in regions associated with reward and drug dependence. Specifically, metabolic increases in the thalamus, as well as metabolic decreases in insular cortex and the periaqueductal gray, were noted. However, compared with males, females exhibited increased metabolism in the preoptic area, primary motor cortex, and the amygdala, and decreased metabolism in the caudate/putamen and medial geniculate nucleus. Methadone and buprenorphine initially abolished these changes uniformly, but subsequently produced their own regional metabolic alterations that varied by treatment and sex. Compared with sex-matched control animals undergoing spontaneous opioid withdrawal, male animals treated with methadone exhibited increased caudate/putamen metabolism, whereas buprenorphine produced increased ventral striatum and motor cortex metabolism in females, and increased ventral striatum and somatosensory cortex metabolism in males. Notably, when treatment effects were compared between sexes, methadone-treated females showed increased cingulate cortex metabolism, whereas buprenorphine-treated females showed decreased metabolism in cingulate cortex and increased metabolism in the globus pallidus. Perhaps the initial similarities in males and females underlie early therapeutic efficacy, whereas these posttreatment sex differences contribute to clinical treatment failure more commonly experienced by the former.

Opioid dependence

PubMed Central

2011-01-01

Introduction Dependence on opioids is a multifactorial condition involving genetic and psychosocial factors. There are three stages to treating opioid dependence. Stabilisation is usually by opioid substitution treatments, and aims to ensure that the drug use becomes independent of mental state (such as craving and mood) and independent of circumstances (such as finance and physical location). The next stage is to withdraw (detox) from opioids. The final stage is relapse prevention. This treatment process contributes to recovery of the individual, which also includes improved overall health and wellbeing, as well as engagement in society. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of drug treatments for stabilisation (maintenance) in people with opioid dependence? What are the effects of drug treatments for withdrawal in people with opioid dependence? What are the effects of drug treatments for relapse prevention in people with opioid dependence? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2011 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 26 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: buprenorphine; clonidine; lofexidine; methadone; naltrexone; and ultra-rapid withdrawal regimens. PMID:21929827

Opioid dependence.

PubMed

Praveen, K Thyarappa; Law, Fergus; O'Shea, Jacinta; Melichar, Jan

2011-09-20

Dependence on opioids is a multifactorial condition involving genetic and psychosocial factors. There are three stages to treating opioid dependence. Stabilisation is usually by opioid substitution treatments, and aims to ensure that the drug use becomes independent of mental state (such as craving and mood) and independent of circumstances (such as finance and physical location). The next stage is to withdraw (detox) from opioids. The final stage is relapse prevention. This treatment process contributes to recovery of the individual, which also includes improved overall health and wellbeing, as well as engagement in society. We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of drug treatments for stabilisation (maintenance) in people with opioid dependence? What are the effects of drug treatments for withdrawal in people with opioid dependence? What are the effects of drug treatments for relapse prevention in people with opioid dependence? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2011 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). We found 26 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. In this systematic review, we present information relating to the effectiveness and safety of the following interventions: buprenorphine; clonidine; lofexidine; methadone; naltrexone; and ultra-rapid withdrawal regimens.

Opiates Modulate Noxious Chemical Nociception through a Complex Monoaminergic/Peptidergic Cascade

PubMed Central

Mills, Holly; Ortega, Amanda; Law, Wenjing; Hapiak, Vera; Summers, Philip; Clark, Tobias

2016-01-01

The ability to detect noxious stimuli, process the nociceptive signal, and elicit an appropriate behavioral response is essential for survival. In Caenorhabditis elegans, opioid receptor agonists, such as morphine, mimic serotonin, and suppress the overall withdrawal from noxious stimuli through a pathway requiring the opioid-like receptor, NPR-17. This serotonin- or morphine-dependent modulation can be rescued in npr-17-null animals by the expression of npr-17 or a human κ opioid receptor in the two ASI sensory neurons, with ASI opioid signaling selectively inhibiting ASI neuropeptide release. Serotonergic modulation requires peptides encoded by both nlp-3 and nlp-24, and either nlp-3 or nlp-24 overexpression mimics morphine and suppresses withdrawal. Peptides encoded by nlp-3 act differentially, with only NLP-3.3 mimicking morphine, whereas other nlp-3 peptides antagonize NLP-3.3 modulation. Together, these results demonstrate that opiates modulate nociception in Caenorhabditis elegans through a complex monoaminergic/peptidergic cascade, and suggest that this model may be useful for dissecting opiate signaling in mammals. SIGNIFICANCE STATEMENT Opiates are used extensively to treat chronic pain. In Caenorhabditis elegans, opioid receptor agonists suppress the overall withdrawal from noxious chemical stimuli through a pathway requiring an opioid-like receptor and two distinct neuropeptide-encoding genes, with individual peptides from the same gene functioning antagonistically to modulate nociception. Endogenous opioid signaling functions as part of a complex, monoaminergic/peptidergic signaling cascade and appears to selectively inhibit neuropeptide release, mediated by a α-adrenergic-like receptor, from two sensory neurons. Importantly, receptor null animals can be rescued by the expression of the human κ opioid receptor, and injection of human opioid receptor ligands mimics exogenous opiates, highlighting the utility of this model for dissecting opiate signaling in mammals. PMID:27194330

Blockade of NMDA receptors prevents analgesic tolerance to repeated transcutaneous electrical nerve stimulation (TENS) in rats

PubMed Central

Hingne, Priyanka M.; Sluka, Kathleen A.

2008-01-01

Repeated daily application transcutaneous electrical nerve stimulation (TENS) results in tolerance, at spinal opioid receptors, to the anti-hyperalgesia produced by TENS. Since N-Methyl-D-Aspartate (NMDA) receptor antagonists prevent analgesic tolerance to opioid agonists we hypothesized that blockade of NMDA receptors will prevent tolerance to TENS. In rats with knee joint inflammation, TENS was applied for 20 minute daily at high frequency (100 Hz), low frequency (4 Hz), or sham TENS. Rats were treated with the NMDA antagonist MK-801 (0.01 mg/kg-0.1 mg/kg) or vehicle daily before TENS. Paw withdrawal thresholds were tested before and after inflammation, and before and after TENS treatment for 4 days. On day 1 TENS reversed the decreased mechanical withdrawal threshold induced by joint inflammation. On day 4 TENS had no effect on the decreased withdrawal threshold in the group treated with vehicle demonstrating development of tolerance. However, in the group treated with 0.1 mg/kg MK-801, TENS significantly reversed the mechanical withdrawal thresholds on day 4 demonstrating that tolerance did not develop. Vehicle treated animals developed cross-tolerance at spinal opioid receptors. Treatment with MK-801 reversed this cross-tolerance at spinal opioid receptors. In summary, blockade of NMDA receptors prevents analgesic tolerance to daily TENS by preventing tolerance at spinal opioid receptors. Perspective Tolerance observed to the clinical treatment of TENS could be prevented by administration of pharmaceutical agents with NMDA receptors activity such as ketamine or dextromethorphan. PMID:18061543

The ibogaine medical subculture.

PubMed

Alper, Kenneth R; Lotsof, Howard S; Kaplan, Charles D

2008-01-04

Ibogaine is a naturally occurring psychoactive indole alkaloid that is used to treat substance-related disorders in a global medical subculture, and is of interest as an ethnopharmacological prototype for experimental investigation and possible rational pharmaceutical development. The subculture is also significant for risks due to the lack of clinical and pharmaceutical standards. This study describes the ibogaine medical subculture and presents quantitative data regarding treatment and the purpose for which individuals have taken ibogaine. All identified ibogaine "scenes" (defined as a provider in an associated setting) apart from the Bwiti religion in Africa were studied with intensive interviewing, review of the grey literature including the Internet, and the systematic collection of quantitative data. Analysis of ethnographic data yielded a typology of ibogaine scenes, "medical model", "lay provider/treatment guide", "activist/self-help", and "religious/spiritual". An estimated 3414 individuals had taken ibogaine as of February 2006, a fourfold increase relative to 5 years earlier, with 68% of the total having taken it for the treatment of a substance-related disorder, and 53% specifically for opioid withdrawal. Opioid withdrawal is the most common reason for which individuals took ibogaine. The focus on opioid withdrawal in the ibogaine subculture distinguishes ibogaine from other agents commonly termed "psychedelics", and is consistent with experimental research and case series evidence indicating a significant pharmacologically mediated effect of ibogaine in opioid withdrawal.

Perioperative pharmacokinetics of methadone in adolescents.

PubMed

Sharma, Anshuman; Tallchief, Danielle; Blood, Jane; Kim, Thomas; London, Amy; Kharasch, Evan D

2011-12-01

Methadone is frequently administered to adults experiencing anesthesia and receiving pain treatment. Methadone pharmacokinetics in adults are well characterized, including the perioperative period. Methadone is also used in children. There is, however, no information on methadone pharmacokinetics in children of any age. The purpose of this investigation was to determine the pharmacokinetics of intravenous methadone in children undergoing surgery. Perioperative opioid-sparing effects were also assessed. Eligible subjects were children 5-18 yr undergoing general anesthesia and surgery, with an anticipated postoperative inpatient stay exceeding 3 days. Three groups of 10 to 11 patients each received intravenous methadone hydrochloride after anesthetic induction in ascending dose groups of 0.1, 0.2, and 0.3 mg/kg (up to 20 mg). Anesthetic care was not otherwise changed. Venous blood was obtained for 4 days, for stereoselective determination of methadone and metabolites. Pain assessments were made each morning. Daily and total opioid consumption was determined. Perioperative opioid consumption and pain was determined in a second cohort, which was matched to age, sex, race, ethnicity, surgical procedure, and length of stay, but not receiving methadone. The final methadone study cohort was 31 adolescents (14 ± 2 yr, range 10-18) undergoing major spine surgery for a diagnosis of scoliosis. Methadone pharmacokinetics were linear over the dose range 0.1-0.3 mg/kg. Disposition was stereoselective. Methadone administration did not dose-dependently affect postoperative pain scores, and did not dose-dependently decrease daily or total postoperative opioid consumption in spinal fusion patients. Methadone enantiomer disposition in adolescents undergoing surgery was similar to that in healthy adults.

The oxytocin analogue carbetocin prevents emotional impairment and stress-induced reinstatement of opioid-seeking in morphine-abstinent mice.

PubMed

Zanos, Panos; Georgiou, Polymnia; Wright, Sherie R; Hourani, Susanna M; Kitchen, Ian; Winsky-Sommerer, Raphaëlle; Bailey, Alexis

2014-03-01

The main challenge in treating opioid addicts is to maintain abstinence due to the affective consequences associated with withdrawal which may trigger relapse. Emerging evidence suggests a role of the neurohypophysial peptide oxytocin (OT) in the modulation of mood disorders as well as drug addiction. However, its involvement in the emotional consequences of drug abstinence remains unclear. We investigated the effect of 7-day opioid abstinence on the oxytocinergic system and assessed the effect of the OT analogue carbetocin (CBT) on the emotional consequences of opioid abstinence, as well as relapse. Male C57BL/6J mice were treated with a chronic escalating-dose morphine regimen (20-100 mg/kg/day, i.p.). Seven days withdrawal from this administration paradigm induced a decrease of hypothalamic OT levels and a concomitant increase of oxytocin receptor (OTR) binding in the lateral septum and amygdala. Although no physical withdrawal symptoms or alterations in the plasma corticosterone levels were observed after 7 days of abstinence, mice exhibited increased anxiety-like and depressive-like behaviors and impaired sociability. CBT (6.4 mg/kg, i.p.) attenuated the observed negative emotional consequences of opioid withdrawal. Furthermore, in the conditioned place preference paradigm with 10 mg/kg morphine conditioning, CBT (6.4 mg/kg, i.p.) was able to prevent the stress-induced reinstatement to morphine-seeking following extinction. Overall, our results suggest that alterations of the oxytocinergic system contribute to the mechanisms underlying anxiety, depression, and social deficits observed during opioid abstinence. This study also highlights the oxytocinergic system as a target for developing pharmacotherapy for the treatment of emotional impairment associated with abstinence and thereby prevention of relapse.

Efficacy of opioids versus placebo in chronic pain: a systematic review and meta-analysis of enriched enrollment randomized withdrawal trials.

PubMed

Meske, Diana S; Lawal, Oluwadolapo D; Elder, Harrison; Langberg, Valerie; Paillard, Florence; Katz, Nathaniel

2018-01-01

Opioids have been used for millennia for the treatment of pain. However, the long-term efficacy of opioids to treat chronic non-cancer pain continues to be debated. To evaluate opioids' efficacy in chronic non-cancer pain, we performed a meta-analysis of published clinical trials for μ-opioid receptor agonists performed for US Food and Drug Administration approval. MEDLINE and Cochrane trial register were searched for enriched enrollment randomized withdrawal studies (before June 2016). Selection criteria included: adults, ≥10 subjects per arm, any chronic pain condition, double-blind treatment period lasting ≥12 weeks, and all μ-agonist opioids approved in the USA. Fifteen studies met criteria. Opioid efficacy was statistically significant ( p <0.001) versus placebo for pain intensity (standardized mean difference: -0.416), ≥30% and ≥50% improvement in pain (risk difference: 0.166 and 0.137), patient global impression of change (0.163), and patient global assessment of study medication (0.194). There were minor benefits on physical function and no effect on mental function. Opioids are efficacious in the treatment of chronic non-cancer pain for up to 3 months in randomized controlled trials. This should be considered, alongside data on opioid safety, in the use of opioids for the treatment of chronic pain.

Peptidase inhibitors reduce opiate narcotic withdrawal signs, including seizure activity, in the rat.

PubMed

Pinsky, C; Dua, A K; LaBella, F S

1982-07-15

Narcotic withdrawal was precipitated by administration of naloxone in a low dose at 2 h after the final dose of morphine in a 9-day dependency-inducing schedule. Withdrawal was characterized by leaps, increased nocifensor activity and by cerebral cortical epileptiform activity, the latter not generally reported to be prominent in narcotic withdrawal. Single large doses of morphine did not provoke epileptiform activity at 2 h postinjection but did induce an acute opioid dependency wherein a moderately high dose of naloxone, ineffective in non-dependent rats, provoked upward leaping and electrocortical epileptiform activity. Pretreatment of the 9-day dependent rats with peptidase inhibitors, administered intracerebroventricularly, significantly reduced withdrawal severity including the epileptiform activity. We propose that peptidase inhibitors protect certain species of endogenous opioids and/or other neuropeptides that tend to suppress expression of the narcotic withdrawal syndrome. Furthermore, our findings suggest that epileptiform activity is a nascent form of cerebral activity hitherto largely unnoticed in narcotic withdrawal and that neuropeptides may be involved in certain epileptic states.

Rectal methadone in cancer patients with pain. A preliminary clinical and pharmacokinetic study.

PubMed

Ripamonti, C; Zecca, E; Brunelli, C; Rizzio, E; Saita, L; Lodi, F; De Conno, F

1995-10-01

Cancer pain can be treated in most cases with oral analgesics. However, during their clinical history, 53% to 70% of patients will need alternative routes of opioid administration. The rectal administration of opioids is a simple alternative route for many patients. There are no data in the literature regarding the pharmacodynamics and pharmacokinetics of rectal methadone. We evaluated the analgesia, tolerability and absorption profile of methadone hydrochloride in six opioid-naive cancer patients with pain. A blood sample was collected before administration of a single dose of drug (10 mg) and then again after fixed times. At these fixed times the patients were asked about pain, nausea and drowsiness by means of a visual analogue scale of 0-100 mm (VAS). Pain relief was statistically significant as early as 30 minutes and up to eight hours after methadone administration. None of the patients reported significant side effects. The pharmacokinetics of rectal methadone showed rapid and extensive distribution phases followed by a slow elimination phase. Rectal methadone can be considered an effective analgesic therapy for patients with cancer pain for whom oral and/or parenteral opioids are not indicated or available.

The CLOSED trial; CLOnidine compared with midazolam for SEDation of paediatric patients in the intensive care unit: study protocol for a multicentre randomised controlled trial

PubMed Central

Neubert, Antje; Baarslag, Manuel Alberto; van Dijk, Monique; van Rosmalen, Joost; Standing, Joseph F; Sheng, Yucheng; Rascher, Wolfgang; Roberts, Deborah; Winslade, Jackie; Rawcliffe, Louise; Hanning, Sara M; Metsvaht, Tuuli; Giannuzzi, Viviana; Larsson, Peter; Pokorná, Pavla; Simonetti, Alessandra; Tibboel, Dick

2017-01-01

Introduction Sedation is an essential part of paediatric critical care. Midazolam, often in combination with opioids, is the current gold standard drug. However, as it is a far-from-ideal agent, clonidine is increasingly being used in children. This drug is prescribed off-label for this indication, as many drugs in paediatrics are. Therefore, the CLOSED trial aims to provide data on the pharmacokinetics, safety and efficacy of clonidine for the sedation of mechanically ventilated patients in order to obtain a paediatric-use marketing authorisation. Methods and analysis The CLOSED study is a multicentre, double-blind, randomised, active-controlled non-inferiority trial with a 1:1 randomisation between clonidine and midazolam. Both treatment groups are stratified according to age in three groups with the same size: <28 days (n=100), 28 days to <2 years (n=100) and 2–18 years (n=100). The primary end point is defined as the occurrence of sedation failure within the study period. Secondary end points include a pharmacokinetic/pharmacodynamic relationship, pharmacogenetics, occurrence of delirium and withdrawal syndrome, opioid consumption and neurodevelopment in the neonatal age group. Logistic regression will be used for the primary end point, appropriate statistics will be used for the secondary end points. Ethics Written informed consent will be obtained from the parents/caregivers. Verbal or deferred consent will be used in the sites where national legislation allows. The study has institutional review board approval at recruiting sites. The results will be published in a peer-reviewed journal and shared with the worldwide medical community. Trial Registration EudraCT: 2014-003582-24; Clinicaltrials.gov: NCT02509273; pre-results. PMID:28637741

BUPRENORPHINE ABUSE IN INDIA : AN UPDATE

PubMed Central

Sharma, Yogesh; Mattoo, S.K.

1999-01-01

This study reviews the available Indian literature on buprenorphine abuse. Buprenorphine was introduced in 1986; the abuse, first noticed in 1987, increased rapidly till 1994, and then decreased gradually. Initiated through other addicts and medical practitioners, the abuse was mostly as a cheap, easily and legally available substitute for opioids. The typical young adult male abuser used an intravenous cocktail with diazepam, pheneramine or promethazine for a better kick. The withdrawal syndrome was typical of the opioids and without an expected delayed onset. Complications of pseudoaneurysm and recurrent koro in repeated withdrawal were reported. Buprenorphine as a detoxifying agent for opioids reportedly gave better symptom control in the first week but high rates of dependence induction were reported. The Indian data tends to caution against the Western enthusiasm to use buprenorphine for detoxification or maintenance of opioid abusers. PMID:21455379

Noradrenaline Triggers GABAA Inhibition of Bed Nucleus of the Stria Terminalis Neurons Projecting to the Ventral Tegmental Area

PubMed Central

Dumont, Éric C.; Williams, John T.

2014-01-01

The lateral part of the ventral bed nucleus of the stria terminalis (vlBNST) is a critical site for the antiaversive effects of noradrenergic drugs during opioid withdrawal. The objective of the present study is to identify the cellular action(s) of noradrenaline in the vlBNST after withdrawal from a 5 d treatment with morphine. The vlBNST is a heterogeneous cell group with multiple efferent projections. Therefore, neurons projecting to the midbrain were identified by retrograde transport of fluorescent microspheres injected in the ventral tegmental area (VTA). Whole-cell voltage clamp recordings of these neurons and of those sharing physiological properties were done in brain slices. Noradrenaline activated α1-adrenergic receptors to increase GABAA-IPSC frequency. Noradrenaline produced a similar increase in GABAA-IPSCs during acute opioid withdrawal, but this increase resulted from activation of β-adrenergic receptors, adenylyl cyclase, and protein kinase A, as well as α1-adrenergic receptors. Given that neurons in the vlBNST send an excitatory projection to the VTA, noradrenaline may reduce excitatory drive to mesolimbic dopamine cells. This mechanism might contribute to the withdrawal-induced inhibition of dopamine neurons and explain how noradrenergic drugs microinjected into the vlBNST reduce aversive aspects of opioid withdrawal. PMID:15385602

Comparative Trial to Study the Effectiveness of Clonidine Hydrochloride and Buprenorphine-Naloxone in Opioid Withdrawal – A Hospital Based Study

PubMed Central

Farhat, Samina; Rather, Yasir Hassan; Abbas, Zaffar

2015-01-01

Objectives: Prevalence of opioid addiction has alarmingly increased over the recent years. In South Asian region alone there are more than 10 million opioid abusers amounting to 2% of world population. Detoxification remains to be the first step for the successful treatment of opioid addiction. The present study was carried out to compare the relative efficacy and safety of buprenorphine –naloxone and clonidine hydrochloride in the detoxification of opioid-dependents. Materials and Methods: Present trial was conducted at De- addiction centre of Institute of Mental and Neurosciences (IMNS), GMC Srinagar. Fifty four (54) treatment seeking subjects, 15-50 years of age, fulfilling DSM-1V TR (American Psychiatric association`s Mental Disorders-1V text revision) criteria for opioid dependence were included and randomized into two groups. The groups received either clonidine hydrochloride (Group A) or buprenorphine- naloxone (Bup-Nax) (Group B) for the duration of 10 days. The efficacy of the two drugs in controlling the opioid withdrawal was evaluated by Clinical Opioid Withdrawal Scale (COWS) and their effect on the desire for the abused substance was measured by Visual Analogue Scale (VAS). The safety of the two drugs was measured by taking the side effect profile of the two compared drugs into consideration. Results: There was significant difference of COWS-score between the two groups which was evident from day 3 (14.85 ± 3.43 vs. 11.67 ± 2.40, p<0.005) and continued till day 6 (2.56 ± 1.40 vs. 0.30 ± 0.61, p<0.005), for Group A and group B respectively. The effect of two drugs in controlling the craving for the abused substance also showed significant difference from day 2 (66.30 ± 10.80 vs. 47.40 ± 12.90, p<0.005) till day 5 (7.78 ± 6.41 vs. 1.85 ± 6.22, p<0.005), for Group A and Group B respectively. Conclusion: Administration of buprenorphine-naloxone was more efficient in reducing the signs and symptoms of opioid withdrawal and in controlling the craving for the abused substance during the first few days of detoxification. PMID:25738001

Models of the Opiate System in Self-Injurious Behavior: A Reply.

ERIC Educational Resources Information Center

Demet, Edward M.; Sandman, Curt A.

1991-01-01

This paper answers criticism (EC 601 030) of the authors' work regarding opioid explanations of self-injurious behavior. Possible withdrawal effects are ruled out as an explanation, in favor of opioid excess leading to sensory depression and addiction to relative excesses of opioid activity in the brain. Alternative models of consequences of…

Very low dose naltrexone addition in opioid detoxification: a randomized, controlled trial.

PubMed

Mannelli, Paolo; Patkar, Ashwin A; Peindl, Kathi; Gorelick, David A; Wu, Li-Tzy; Gottheil, Edward

2009-04-01

Although current treatments for opioid detoxification are not always effective, medical detoxification remains a required step before long-term interventions. The use of opioid antagonist medications to improve detoxification has produced inconsistent results. Very low dose naltrexone (VLNTX) was recently found to reduce opioid tolerance and dependence in animal and clinical studies. We decided to evaluate safety and efficacy of VLNTX adjunct to methadone in reducing withdrawal during detoxification. In a multi-center, double-blind, randomized study at community treatment programs, where most detoxifications are performed, 174 opioid-dependent subjects received NTX 0.125 mg, 0.250 mg or placebo daily for 6 days, together with methadone in tapering doses. VLNTX-treated individuals reported attenuated withdrawal symptoms [F = 7.24 (2,170); P = 0.001] and reduced craving [F = 3.73 (2,107); P = 0.03]. Treatment effects were more pronounced at discharge and were not accompanied by a significantly higher retention rate. There were no group differences in use of adjuvant medications and no treatment-related adverse events. Further studies should explore the use of VLNTX, combined with full and partial opioid agonist medications, in detoxification and long-term treatment of opioid dependence.

Lubiprostone for the treatment of opioid-induced bowel dysfunction.

PubMed

Wong, Banny S; Camilleri, Michael

2011-04-01

Opioid-induced bowel dysfunction (OBD) is a prevalent condition that leads to reduced opioid use, human suffering and a high burden and cost on the healthcare system. Opioid-induced constipation (OIC) is the most troublesome aspect of OBD, for which standard laxatives are often ineffective. A major unmet need is effective and safe OIC treatment without inhibiting opioid analgesia or inducing opioid withdrawal symptoms. Recent data indicate that lubiprostone, a locally acting type 2 chloride channel activator, approved for the treatment of chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation, may be effective in treating OBD. The areas covered are: i) an overview of clinical trials of lubiprostone in the treatment of OBD based on peer-reviewed literature and congress materials from 2005 to 2010; and ii) an evaluation of the efficacy and potential mechanisms of action of lubiprostone in the treatment of OBD. Lubiprostone has potential in treating OBD and deserves additional study. Lubiprostone's ability to promote fluid secretion locally at the apical membrane of intestinal epithelial cells ensures it does not provoke opioid withdrawal or compromise analgesia. Lubiprostone seems safe for long-term use in CIC patients, and a similar safety profile is anticipated in OBD.

Opioid Use Disorders

PubMed Central

Sharma, Bikash; Bruner, Ann; Barnett, Gabrielle; Fishman, Marc

2016-01-01

Opioid use and addiction in adolescents and young adults, including heroin and non-medical use of prescription opioids, is a serious and growing health problem of epidemic proportions. Opioid use has devastating consequences for youth and their families, including: progression to full addiction, severe psychosocial impairment, HCV and HIV transmission with injection use, exacerbation of co-occurring psychiatric disorders, overdose, and death. This chapter will provide an overview of opioid use disorders (OUDs) in youth, including: etiologic factors, epidemiology, consequences, clinical presentation and course, assessment and diagnosis, overdose, detoxification, and treatment. Opioid overdose is a life-threatening emergency. Respiratory depression should be treated with naloxone, and respiratory support if necessary. Overdose should always be utilized as an opportunity to initiate addiction treatment. Opioid withdrawal management (detoxification) is often a necessary, but never sufficient, component of treatment for OUDs. Medications used in the treatment of withdrawal may include buprenorphine, clonidine and others for relief of symptoms. Treatment for OUDs is effective but treatment capacity is alarmingly limited and under-developed. Although there is a limited evidence base for youth specific treatment, emerging consensus supports the incorporation of relapse prevention medications such as buprenorphine and extended release naltrexone into comprehensive psychosocial treatment including counseling and family involvement. PMID:27338968

Analysis of opioid-mediated analgesia in Phase III studies of methylnaltrexone for opioid-induced constipation in patients with chronic noncancer pain

PubMed Central

Webster, Lynn R; Brenner, Darren M; Barrett, Andrew C; Paterson, Craig; Bortey, Enoch; Forbes, William P

2015-01-01

Background Subcutaneous methylnaltrexone is efficacious and well tolerated for opioid-induced constipation (OIC) but may theoretically disrupt opioid-mediated analgesia. Methods Opioid use, pain intensity, and opioid withdrawal (Objective Opioid Withdrawal Scale [OOWS] and Subjective Opiate Withdrawal Scale [SOWS] scores) were reported in a randomized, double-blind trial with an open-label extension (RCT) and an open-label trial (OLT) evaluating safety in adults with chronic noncancer pain. In the RCT, patients taking ≥50 mg of oral morphine equivalents daily with <3 rescue-free bowel movements weekly received methyl naltrexone 12 mg once daily (n=150), every other day (n=148), or placebo (n=162) for 4 weeks, followed by open-label methylnaltrexone 12 mg (as needed [prn]; n=364) for 8 weeks. In the OLT, patients (n=1,034) on stable opioid doses with OIC received methylnaltrexone 12 mg prn for up to 48 weeks. Results Minimal fluctuations of median morphine equivalent dose from baseline (BL) were observed in the RCT double-blind period (BL, 154.8–161.0 mg/d; range, 137.1–168.0 mg/d), RCT open-label period (BL, 156.3–174.6; range, 144.0–180.0) and OLT (BL, 120 mg/d; range, 117.3–121.1 mg/d). No significant change from BL in pain intensity score occurred in any group at weeks 2 or 4 (both P≥0.1) of the RCT double-blind period, and scores remained stable during the open-label period and in the OLT (mean change, −0.2 to 0.1). Changes from BL in OOWS and SOWS scores during the double-blind period were not significantly impacted by methylnaltrexone exposure at weeks 2 or 4 (P>0.05 for all). Conclusion Methylnaltrexone did not affect opioid-mediated analgesia in patients with chronic noncancer pain and OIC. PMID:26586963

Assessment of extended-release opioid analgesics for the treatment of chronic pain.

PubMed

Gudin, Jeffrey A

2013-03-01

Approximately 3.8 million patients annually receive extended-release (ER) or long-acting opioid prescriptions in the outpatient setting, around half of which are written by primary care physicians. Compared with short-acting, immediate-release (IR) formulations, ER and oral long-acting opioid analgesics are associated with clinical advantages, such as extended periods of time during which drug plasma levels are within the therapeutic range, decreased peak-to-trough fluctuations, and prolonged analgesia over the dosing period. Additionally, ER opioids offer a more convenient, less frequent dosing regimen to chronic pain patients who are often taking several concomitant medications. The increased utilization of ER opioids has been accompanied by a rise in the misuse and abuse of these formulations. Certain pharmacokinetic parameters (e.g., longer time to maximum drug plasma concentration, lower maximum drug plasma concentration) may decrease the abuse potential of intact ER opioids by limiting the positive subjective and reinforcing effects relative to IR formulations. Putative abuse-deterrent formulations have also recently been introduced to impede physical manipulation of these formulations, or reduce the harm resulting from such behavior. Such formulations may represent an incremental advance to reduce non-oral forms of abuse. This article reviews the pharmacokinetic profiles and abuse-deterrent features of newer ER opioid analgesics for the treatment of moderate to severe chronic pain.

Ibogaine treatment outcomes for opioid dependence from a twelve-month follow-up observational study.

PubMed

Noller, Geoffrey E; Frampton, Chris M; Yazar-Klosinski, Berra

2018-01-01

The psychoactive indole alkaloid ibogaine has been associated with encouraging treatment outcomes for opioid dependence. The legal status of ibogaine in New Zealand provides a unique opportunity to evaluate durability of treatment outcomes. To examine longitudinal treatment effects over a 12-month period among individuals receiving legal ibogaine treatment for opioid dependence. This observational study measured addiction severity as the primary outcome in 14 participants (50% female) over 12 months post-treatment using the Addiction Severity Index-Lite (ASI-Lite) following a single ibogaine treatment by either of two treatment providers. Secondary effects on depression were assessed via the Beck Depression Inventory-II (BDI-II). The Subjective Opioid Withdrawal Scale (SOWS) was collected before and immediately after treatment to measure opioid withdrawal symptoms. Nonparametric comparisons via Friedman Test between baseline and 12-month follow-up for participants completing all interviews (n = 8) showed a significant reduction for the ASI-Lite drug use (p = 0.002) composite score. Reductions in BDI-II scores from baseline to 12-month follow-up were also significant (p < 0.001). Significant reductions in SOWS scores for all participants (n = 14) were also observed acutely after treatment (p = 0.015). Patients with partial data (n = 4) also showed reductions in ASI-Lite drug use scores and family/social status problems. One patient enrolled in the study died during treatment. A single ibogaine treatment reduced opioid withdrawal symptoms and achieved opioid cessation or sustained reduced use in dependent individuals as measured over 12 months. Ibogaine's legal availability in New Zealand may offer improved outcomes where legislation supports treatment providers to work closely with other health professionals.

42 CFR 8.6 - Withdrawal of approval of accreditation bodies.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 1 2012-10-01 2012-10-01 false Withdrawal of approval of accreditation bodies. 8.6 Section 8.6 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID TREATMENT PROGRAMS Accreditation § 8.6 Withdrawal of approval of...

42 CFR 8.6 - Withdrawal of approval of accreditation bodies.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 1 2011-10-01 2011-10-01 false Withdrawal of approval of accreditation bodies. 8.6 Section 8.6 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID TREATMENT PROGRAMS Accreditation § 8.6 Withdrawal of approval of...

42 CFR 8.6 - Withdrawal of approval of accreditation bodies.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 1 2014-10-01 2014-10-01 false Withdrawal of approval of accreditation bodies. 8.6 Section 8.6 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID TREATMENT PROGRAMS Accreditation § 8.6 Withdrawal of approval of...

42 CFR 8.6 - Withdrawal of approval of accreditation bodies.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 1 2013-10-01 2013-10-01 false Withdrawal of approval of accreditation bodies. 8.6 Section 8.6 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID TREATMENT PROGRAMS Accreditation § 8.6 Withdrawal of approval of...

Efficacy of Tramadol Extended-Release for Opioid Withdrawal: A Randomized Clinical Trial.

PubMed

Dunn, Kelly E; Tompkins, D Andrew; Bigelow, George E; Strain, Eric C

2017-09-01

Opioid use disorder (OUD) is a significant public health problem. Supervised withdrawal (ie, detoxification) from opioids using clonidine or buprenorphine hydrochloride is a widely used treatment. To evaluate whether tramadol hydrochloride extended-release (ER), an approved analgesic with opioid and nonopioid mechanisms of action and low abuse potential, is effective for use in supervised withdrawal settings. A randomized clinical trial was conducted in a residential research setting with 103 participants with OUD. Participants' treatment was stabilized with morphine, 30 mg, administered subcutaneously 4 times daily. A 7-day taper using clonidine (n = 36), tramadol ER (n = 36), or buprenorphine (n = 31) was then instituted, and patients were crossed-over to double-blind placebo during a post-taper period. The study was conducted from October 25, 2010, to June 23, 2015. Retention, withdrawal symptom management, concomitant medication utilization, and naltrexone induction. Results were analyzed over time and using area under the curve for the intention-to-treat and completer groups. Of the 103 participants, 88 (85.4%) were men and 43 (41.7%) were white; mean (SD) age was 28.9 (10.4) years. Buprenorphine participants (28 [90.3%]) were significantly more likely to be retained at the end of the taper compared with clonidine participants (22 [61.1%]); tramadol ER retention was intermediate and did not differ significantly from that of the other groups (26 [72.2%]; χ2 = 8.5, P = .01). Time-course analyses of withdrawal revealed significant effects of phase (taper, post taper) for the Clinical Opiate Withdrawal Scale (COWS) score (taper mean, 5.19 [SE, .26]; post-taper mean, 3.97 [SE, .23]; F2,170 = 3.6, P = .03) and Subjective Opiate Withdrawal Scale (SOWS) score (taper mean,8.81 [SE, .40]; post-taper mean, 4.14 [SE, .30]; F2,170 = 15.7, P < .001), but no group effects or group × phase interactions. Analyses of area under the curve of SOWS total scores showed significant reductions (F2,159 = 17.7, P < .001) in withdrawal severity between the taper and post-taper periods for clonidine (taper mean, 13.1; post-taper mean, 3.2; P < .001) and tramadol ER (taper mean, 7.4; post-taper mean, 2.8; P = .03), but not buprenorphine (taper mean, 6.4; post-taper mean, 7.4). Use of concomitant medication increased significantly (F2,159 = 30.7,  P < .001) from stabilization to taper in the clonidine (stabilization mean, 0.64 [SE, .05]; taper mean, 1.54 [SE, .10]; P < .001) and tramadol ER (stabilization mean, 0.53 [SE, .05]; taper mean, 1.19 [SE, .09]; P = .003) groups and from stabilization to post taper in the buprenorphine group (stabilization mean, 0.46 [SE, .05] post-taper mean, 1.17 [SE, .09]; P = .006), suggesting higher withdrawal for those groups during those periods. Naltrexone initiation was voluntary and the percentage of participants choosing naltrexone therapy within the clonidine (8 [22.2%]), tramadol ER (7 [19.4%]), or buprenorphine (3 [9.7%]) groups did not differ significantly (χ2 = 2.5, P = .29). The results of this trial suggest that tramadol ER is more effective than clonidine and comparable to buprenorphine in reducing opioid withdrawal symptoms during a residential tapering program. Data support further examination of tramadol ER as a method to manage opioid withdrawal symptoms. Clinicaltrials.gov Identifier: NCT01188421.

Dramatic Increases in Maternal Opioid Use and Neonatal Abstinence Syndrome

MedlinePlus

... estimated 21,732 infants were born with NAS —equivalent to one baby suffering from opiate withdrawal born ... for back pain shows missed opportunities to prescribe non-opioid medications ( June 2018 ) Methadone and buprenorphine reduce ...

Skin β-endorphin mediates addiction to UV light.

PubMed

Fell, Gillian L; Robinson, Kathleen C; Mao, Jianren; Woolf, Clifford J; Fisher, David E

2014-06-19

UV light is an established carcinogen, yet evidence suggests that UV-seeking behavior has addictive features. Following UV exposure, epidermal keratinocytes synthesize proopiomelanocortin (POMC) that is processed to melanocyte-stimulating hormone, inducing tanning. We show that, in rodents, another POMC-derived peptide, β-endorphin, is coordinately synthesized in skin, elevating plasma levels after low-dose UV. Increases in pain-related thresholds are observed and reversed by pharmacologic opioid antagonism. Opioid blockade also elicits withdrawal signs after chronic UV exposure. This effect was sufficient to guide operant behavioral choices to avoidance of opioid withdrawal (conditioned place aversion). These UV-induced nociceptive and behavioral effects were absent in β-endorphin knockout mice and in mice lacking p53-mediated POMC induction in epidermal keratinocytes. Although primordial UV addiction, mediated by the hedonic action of β-endorphin and anhedonic effects of withdrawal, may theoretically have enhanced evolutionary vitamin D biosynthesis, it now may contribute to the relentless rise in skin cancer incidence in humans. Copyright © 2014 Elsevier Inc. All rights reserved.

Skin β-endorphin mediates addiction to ultraviolet light

PubMed Central

Fell, Gillian L.; Robinson, Kathleen C.; Mao, Jianren; Woolf, Clifford J.; Fisher, David E.

2014-01-01

SUMMARY Ultraviolet light is an established carcinogen yet evidence suggests that UV-seeking behavior has addictive features. Following UV exposure, epidermal keratinocytes synthesize Proopiomelanocortin that is processed to Melanocyte Stimulating Hormone, inducing tanning. We show that in rodents another POMC-derived peptide, β-endorphin, is coordinately synthesized in skin, elevating plasma levels after low-dose UV. Increases in pain-related thresholds are observed, and reversed by pharmacologic opioid antagonism. Opioid blockade also elicits withdrawal signs after chronic UV exposure. This effect was sufficient to guide operant behavioral choices to avoidance of opioid withdrawal (conditioned place aversion). These UV-induced nociceptive and behavioral effects were absent in β-endorphin knockout mice and in mice lacking p53-mediated POMC induction in epidermal keratinocytes. While primordial UV addiction, mediated by the hedonic action of β-endorphin and anhedonic effects of withdrawal, may theoretically have enhanced evolutionary vitamin D biosynthesis, it now may contribute to the relentless rise in skin cancer incidence in man. PMID:24949966

The Behavioral Effects of a Mixed Efficacy Antinociceptive Peptide, VRP26, Following Chronic Administration in Mice

PubMed Central

Anand, Jessica P.; Boyer, Brett T.; Mosberg, Henry I.; Jutkiewicz, Emily M.

2016-01-01

Rationale VRP26 displays mu opioid receptor agonist and delta opioid receptor antagonist activity in vitro, a pharmacological profile purported to produce reduced tolerance, dependence, and rewarding effects. We hypothesized that VRP26 would display reduced adverse effects after chronic administration as compared with the traditional opioid analgesic fentanyl. Objective To explore the development of tolerance, dependence and conditioned place preference of VRP26 as compared with the traditional opioid analgesic fentanyl. Methods The antinociceptive effects of VRP26 and fentanyl were assessed using the mouse warm water tail withdrawal (WWTW) assay. Measurement of antinociceptive tolerance and physical dependence occurred after seven days of continuous administration of either fentanyl (0.3 mg/kg/day) or VRP26 (10 mg/kg/day); tolerance was measured by a shift in the antinociceptive dose response curve in the WWTW assay. Physical dependence was determined by observation of withdrawal symptoms after precipitated withdrawal. Rewarding effects were measured by the ability of VRP26 or fentanyl to produce conditioned place preference. Results Fentanyl produced significant tolerance and dependence, as well as significant conditioned place preference. VRP26 produced neither tolerance nor physical dependence, nor did it produce significant conditioned place preference. Conclusions These results suggest that chronic treatment with VRP26 may produce less tolerance or physical dependence than chronic treatment with clinically available mu opioid analgesics such as fentanyl. Additionally, VRP26 produces less rewarding effects than fentanyl. This desirable in vivo profile may be due to the mixed efficacy nature of VRP26 and could provide the framework for safer opioid analgesics. PMID:27117141

Activation of serotonin 5-HT2C receptor suppresses behavioral sensitization and naloxone-precipitated withdrawal symptoms in morphine-dependent mice

PubMed Central

Zhang, Gongliang; Wu, Xian; Zhang, Yong-Mei; Liu, Huan; Jiang, Qin; Pang, Gang; Tao, Xinrong; Dong, Liuyi; Stackman, Robert W.

2015-01-01

Opioid abuse and dependence have evolved into an international epidemic as a significant clinical and social problem with devastating consequences. Repeated exposure to the opioid, for example morphine, can induce profound, long-lasting behavioral sensitization and physical dependence, which are thought to reflect neuroplasticity in neural circuitry. Central serotonin (5-HT) neurotransmission participates in the development of dependence on and the expression of withdrawal from morphine. Serotonin 5-HT2C receptor (5-HT2CR) agonists suppress psychostimulant nicotine or cocaine-induced behavioral sensitization and drug-seeking behavior; however, the impact of 5-HT2CR agonists on behaviors relevant to opioid abuse and dependence has not been reported. In the present study, the effects of 5-HT2CR activation on the behavioral sensitization and naloxone-precipitated withdrawal symptoms were examined in mice underwent repeated exposure to morphine. Male mice received morphine (10 mg/kg, s.c.) to develop behavioral sensitization. Lorcaserin, a 5-HT2CR agonist, prevented the induction and expression, but not the development, of morphine-induced behavioral sensitization. Another cohort of mice received increasing doses of morphine over a 7-day period to induce morphine-dependence. Pretreatment of lorcaserin, or the positive control clonidine (an alpha 2-adrenoceptor agonist), ameliorated the naloxone-precipitated withdrawal symptoms. SB 242084, a selective 5-HT2CR antagonist, prevented the lorcaserin-mediated suppression of behavioral sensitization and withdrawal. Chronic morphine treatment was associated with an increase in the expression of 5-HT2CR protein in the ventral tegmental area, locus coeruleus and nucleus accumbens. These findings suggest that 5-HT2CR can modulate behavioral sensitization and withdrawal in morphine-dependent mice, and the activation of 5-HT2CR may represent a new avenue for the treatment of opioid addiction. PMID:26432939

Effect of Iboga Alkaloids on µ-Opioid Receptor-Coupled G Protein Activation

PubMed Central

Antonio, Tamara; Childers, Steven R.; Rothman, Richard B.; Dersch, Christina M.; King, Christine; Kuehne, Martin; Bornmann, William G.; Eshleman, Amy J.; Janowsky, Aaron; Simon, Eric R.; Reith, Maarten E. A.; Alper, Kenneth

2013-01-01

Objective The iboga alkaloids are a class of small molecules defined structurally on the basis of a common ibogamine skeleton, some of which modify opioid withdrawal and drug self-administration in humans and preclinical models. These compounds may represent an innovative approach to neurobiological investigation and development of addiction pharmacotherapy. In particular, the use of the prototypic iboga alkaloid ibogaine for opioid detoxification in humans raises the question of whether its effect is mediated by an opioid agonist action, or if it represents alternative and possibly novel mechanism of action. The aim of this study was to independently replicate and extend evidence regarding the activation of μ-opioid receptor (MOR)-related G proteins by iboga alkaloids. Methods Ibogaine, its major metabolite noribogaine, and 18-methoxycoronaridine (18-MC), a synthetic congener, were evaluated by agonist-stimulated guanosine-5´-O-(γ-thio)-triphosphate ([35S]GTPγS) binding in cells overexpressing the recombinant MOR, in rat thalamic membranes, and autoradiography in rat brain slices. Results And Significance In rat thalamic membranes ibogaine, noribogaine and 18-MC were MOR antagonists with functional Ke values ranging from 3 uM (ibogaine) to 13 uM (noribogaine and 18MC). Noribogaine and 18-MC did not stimulate [35S]GTPγS binding in Chinese hamster ovary cells expressing human or rat MORs, and had only limited partial agonist effects in human embryonic kidney cells expressing mouse MORs. Ibogaine did not did not stimulate [35S]GTPγS binding in any MOR expressing cells. Noribogaine did not stimulate [35S]GTPγS binding in brain slices using autoradiography. An MOR agonist action does not appear to account for the effect of these iboga alkaloids on opioid withdrawal. Taken together with existing evidence that their mechanism of action also differs from that of other non-opioids with clinical effects on opioid tolerance and withdrawal, these findings suggest a novel mechanism of action, and further justify the search for alternative targets of iboga alkaloids. PMID:24204784

Effect of Iboga alkaloids on µ-opioid receptor-coupled G protein activation.

PubMed

Antonio, Tamara; Childers, Steven R; Rothman, Richard B; Dersch, Christina M; King, Christine; Kuehne, Martin; Bornmann, William G; Eshleman, Amy J; Janowsky, Aaron; Simon, Eric R; Reith, Maarten E A; Alper, Kenneth

2013-01-01

The iboga alkaloids are a class of small molecules defined structurally on the basis of a common ibogamine skeleton, some of which modify opioid withdrawal and drug self-administration in humans and preclinical models. These compounds may represent an innovative approach to neurobiological investigation and development of addiction pharmacotherapy. In particular, the use of the prototypic iboga alkaloid ibogaine for opioid detoxification in humans raises the question of whether its effect is mediated by an opioid agonist action, or if it represents alternative and possibly novel mechanism of action. The aim of this study was to independently replicate and extend evidence regarding the activation of μ-opioid receptor (MOR)-related G proteins by iboga alkaloids. Ibogaine, its major metabolite noribogaine, and 18-methoxycoronaridine (18-MC), a synthetic congener, were evaluated by agonist-stimulated guanosine-5´-O-(γ-thio)-triphosphate ([(35)S]GTPγS) binding in cells overexpressing the recombinant MOR, in rat thalamic membranes, and autoradiography in rat brain slices. In rat thalamic membranes ibogaine, noribogaine and 18-MC were MOR antagonists with functional Ke values ranging from 3 uM (ibogaine) to 13 uM (noribogaine and 18MC). Noribogaine and 18-MC did not stimulate [(35)S]GTPγS binding in Chinese hamster ovary cells expressing human or rat MORs, and had only limited partial agonist effects in human embryonic kidney cells expressing mouse MORs. Ibogaine did not did not stimulate [(35)S]GTPγS binding in any MOR expressing cells. Noribogaine did not stimulate [(35)S]GTPγS binding in brain slices using autoradiography. An MOR agonist action does not appear to account for the effect of these iboga alkaloids on opioid withdrawal. Taken together with existing evidence that their mechanism of action also differs from that of other non-opioids with clinical effects on opioid tolerance and withdrawal, these findings suggest a novel mechanism of action, and further justify the search for alternative targets of iboga alkaloids.

A Stage I Pilot Study of Acceptance and Commitment Therapy for Methadone Detoxification

PubMed Central

Stotts, Angela L.; Green, Charles; Masuda, Akihiko; Grabowski, John; Wilson, Kelly; Northrup, Thomas; Moeller, F. Gerard; Schmitz, Joy

2012-01-01

BACKGROUND While agonist replacement therapies are effective for managing opioid dependence, community treatment programs are increasingly choosing detoxification. Unfortunately, success rates for opioid detoxification are very low, in part, due to physical and psychological symptoms associated with opioid withdrawal. Few behavior therapies specifically address the distressing experiences specific to opioid withdrawal. A novel behavioral treatment, Acceptance and Commitment Therapy (ACT), works from the premise that the avoidance of unpleasant private experiences (thoughts, feelings, bodily sensations) is ubiquitous yet may be pathogenic, resulting in treatment drop-out and further drug use. METHODS This Stage I pilot study developed and tested an ACT-based opioid detoxification behavioral therapy. Opioid dependent patients (N = 56) who were attending a licensed methadone clinic were randomized to receive either 24 individual therapy sessions of ACT or Drug Counseling (DC) in the context of a 6-month methadone dose reduction program. RESULTS While no difference was found on opioid use during treatment, 37% of participants in the ACT condition were successfully detoxified at the end of treatment compared to 19% of those who received DC. Fear of detoxification was also reduced across time in the ACT condition relative to DC. CONCLUSION This first study of ACT to assist opioid detoxification indicates promise. Research is needed to refine specific treatment strategies for this population to further strengthen effects. PMID:22425411

78 FR 48177 - Purdue Pharma L.P.; Withdrawal of Approval of a New Drug Application for Oxycontin

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-07

... or misuse. Both original and reformulated OxyContin are opioid agonist products. Original OxyContin was indicated for the management of moderate to severe pain when a continuous, around-the-clock opioid...

STEP signaling pathway mediates psychomotor stimulation and morphine withdrawal symptoms, but not for reward, analgesia and tolerance

PubMed Central

Kim, Yoon-Jung; Kang, Young; Park, Hye-Yeon; Lee, Jae-Ran; Yu, Dae-Yeul; Murata, Takuya; Gondo, Yoichi; Hwang, Jung Hwan; Kim, Yong-Hoon; Lee, Chul-Ho; Rhee, Myungchull; Han, Pyung-Lim; Chung, Bong-Hyun; Lee, Hyun-Jun; Kim, Kyoung-Shim

2016-01-01

Striatal-enriched protein tyrosine phosphatase (STEP) is abundantly expressed in the striatum, which strongly expresses dopamine and opioid receptors and mediates the effects of many drugs of abuse. However, little is known about the role of STEP in opioid receptor function. In the present study, we generated STEP-targeted mice carrying a nonsense mutation (C230X) in the kinase interaction domain of STEP by screening the N-ethyl-N-nitrosourea (ENU)-driven mutant mouse genomic DNA library and subsequent in vitro fertilization. It was confirmed that the C230X nonsense mutation completely abolished functional STEP protein expression in the brain. STEPC230X−/− mice showed attenuated acute morphine-induced psychomotor activity and withdrawal symptoms, whereas morphine-induced analgesia, tolerance and reward behaviors were unaffected. STEPC230X−/− mice displayed reduced hyperlocomotion in response to intrastriatal injection of the μ-opioid receptor agonist DAMGO, but the behavioral responses to δ- and κ-opioid receptor agonists remained intact. These results suggest that STEP has a key role in the regulation of psychomotor action and physical dependency to morphine. These data suggest that STEP inhibition may be a critical target for the treatment of withdrawal symptoms associated with morphine. PMID:26915673

Pharmacokinetic evaluation of hydrocodone/acetaminophen for pain management.

PubMed

Singla, Aarti; Sloan, Paul

2013-01-01

Hydrocodone/acetaminophen is not only the most commonly prescribed opioid in the United States but also the most common prescription medication written in America. Although original and early trials confirmed its ability to manage acute pain from surgery and musculoskeletal injury, it is perhaps more widely used today in the management of chronic pain. However, the opioid product was introduced for the management of moderate to moderately severe pain. Because it has been greatly abused as a prescription opioid medication, physicians need to be aware of the current knowledge regarding this analgesic drug. This review summarizes the current knowledge of the pharmacokinetics, pharmacodynamics, and metabolism of hydrocodone. Recent information regarding the possibility of hydrocodone as a prodrug for hydromorphone is discussed. The available clinical trials for the use of hydrocodone in the management of acute, chronic, and cancer pain are presented.

Identifying and assessing the substance-exposed infant.

PubMed

Clark, Lisa; Rohan, Annie

2015-01-01

As the rate of opioid prescription grows, so does fetal exposure to opioids during pregnancy. With increasing fetal exposure to both prescription and nonprescription drugs, there has been a concurrent increase in identification of Neonatal Withdrawal Syndrome (NWS) and adaptation difficulties after birth. In addition, extended use of opioids, barbiturates, and benzodiazepines in neonatal intensive care has resulted in iatrogenic withdrawal syndromes. There is a lack of evidence to support the use of any one specific evaluation strategy to identify NWS. Clinicians caring for infants must use a multimethod approach to diagnosis, including interview and toxicology screening. Signs of NWS are widely variable, and reflect dysfunction in autonomic regulation, state control, and sensory and motor functioning. Several assessment tools have been developed for assessing severity of withdrawal in term neonates. These tools assist in determining need and duration of pharmacologic therapy and help in titration of these therapies. Considerable variability exists in the pharmacologic and nonpharmacologic approaches to affected babies across settings. An evidence-based protocol for identification, evaluation, and management of NWS should be in place in every nursery. This article provides an overview of identification and assessment considerations for providers who care for babies at risk for or who are experiencing alterations in state, behavior, and responses after prenatal or iatrogenic exposure to agents associated with the spectrum of withdrawal.

Dual-opioid therapy: changing the paradigm. Introduction.

PubMed

Nicholson, Bruce D

2012-03-01

Morphine sulfate and oxycodone hydrochloride are commonly used for pain management because of their pharmacologic profile, pharmacokinetics, and analgesic potency. However, opioids are associated with a significant adverse event (AE) burden that limits their use in both the acute and the chronic pain settings. Co-administration of opioids demonstrated synergistic analgesia and reduced side effects. Thus, dual-opioid therapy has the potential to enhance the positive analgesic benefits of opioids, while limiting the burden of opioid-related AEs. This symposium proceedings was based on presentations at the 13th World Congress on Pain in August 2010. This program will review the rationale for dual-opioid therapy based on preclinical findings and data from clinical studies showing the efficacy and tolerability profile of a dual-opioid formulation when used to treat acute postoperative pain. Wiley Periodicals, Inc.

Opioid adjuvant strategy: improving opioid effectiveness.

PubMed

Bihel, Frédéric

2016-01-01

Opioid analgesics continue to be the mainstay of pharmacologic treatment of moderate to severe pain. Many patients, particularly those suffering from chronic pain, require chronic high-dose analgesic therapy. Achieving clinical efficacy and tolerability of such treatment regimens is hampered by the appearance of opioid-induced side effects such as tolerance, hyperalgesia and withdrawal syndrome. Among the therapeutic options to improve the opioid effectiveness, this current review focuses on strategies combining opioids to other drugs that can modulate opioid-mediated effects. We will discuss about experimental evidences reported for several potential opioid adjuvants, including N-methyl-D-aspartate receptor antagonists, 5-HT7 agonists, sigma-1 antagonists, I2-R ligands, cholecystokinin antagonists, neuropeptide FF-R antagonists and toll-like receptor 4 antagonists.

Pharmacology of kratom: an emerging botanical agent with stimulant, analgesic and opioid-like effects.

PubMed

Prozialeck, Walter C; Jivan, Jateen K; Andurkar, Shridhar V

2012-12-01

Kratom (Mitragyna speciosa) is a plant indigenous to Thailand and Southeast Asia. Kratom leaves produce complex stimulant and opioid-like analgesic effects. In Asia, kratom has been used to stave off fatigue and to manage pain, diarrhea, cough, and opioid withdrawal. Recently, kratom has become widely available in the United States and Europe by means of smoke shops and the Internet. Analyses of the medical literature and select Internet sites indicate that individuals in the United States are increasingly using kratom for the self-management of pain and opioid withdrawal. Kratom contains pharmacologically active constituents, most notably mitragynine and 7-hydroxymitragynine. Kratom is illegal in many countries. Although it is still legal in the United States, the US Drug Enforcement Administration has placed kratom on its "Drugs and Chemicals of Concern" list. Physicians should be aware of the availability, user habits, and health effects of kratom. Further research on the therapeutic uses, toxic effects, and abuse potential of kratom and its constituent compounds are needed.

The Role of Opioid Analgesics in Geriatric Pain Management.

PubMed

Naples, Jennifer Greene; Gellad, Walid F; Hanlon, Joseph T

2016-11-01

When possible, chronic noncancer pain (CNCP) in older adults should be managed by nonpharmacologic modalities in conjunction with nonopioid analgesics. If moderate-to-severe pain persists despite these approaches, however, nonparenteral opioids may be considered as adjunctive therapy. This article reviews the epidemiology of opioid use and their effectiveness for CNCP in older adults and summarizes important age-related changes in opioid pharmacokinetics and pharmacodynamics that increase the risks of adverse effects in the elderly. Finally, to assist clinicians with selecting appropriate therapy, the article concludes with an evidence-based approach to optimize opioid prescribing in older adults with CNCP. Copyright © 2016 Elsevier Inc. All rights reserved.

Withdrawal from Buprenorphine/Naloxone and Maintenance with a Natural Dopaminergic Agonist: A Cautionary Note.

PubMed

Blum, Kenneth; Oscar-Berman, Marlene; Femino, John; Waite, Roger L; Benya, Lisa; Giordano, John; Borsten, Joan; Downs, William B; Braverman, Eric R; Loehmann, Raquel; Dushaj, Kristina; Han, David; Simpatico, Thomas; Hauser, Mary; Barh, Debmalya; McLaughlin, Thomas

2013-04-23

While numerous studies support the efficacy of methadone and buprenorphine for the stabilization and maintenance of opioid dependence, clinically significant opioid withdrawal symptoms occur upon tapering and cessation of dosage. We present a case study of a 35 year old Caucasian female (Krissie) who was prescribed increasing dosages of prescription opioids after carpel tunnel surgery secondary to chronic pain from reflex sympathetic dystrophy and fibromyalgia. Over the next 5 years, daily dosage requirements increased to over 80 mg of Methadone and 300 ug/hr Fentanyl transdermal patches, along with combinations of 12-14 1600 mcg Actig lollipop and oral 100 mg Morphine and 30 mg oxycodone 1-2 tabs q4-6hr PRN for breakthrough pain. Total monthly prescription costs including supplemental benzodiazepines, hypnotics and stimulants exceeded $50,000. The patient was subsequently transferred to Suboxone® in 2008, and the dosage was gradually tapered until her admission for inpatient detoxification with KB220Z a natural dopaminergic agonist. We carefully documented her withdrawal symptoms when she precipitously stopped taking buprenorphine/naloxone and during follow-up while taking KB220Z daily. We also genotyped the patient using a reward gene panel including (9 genes 18 alleles): DRD 2,3,4; MOA-A; COMT; DAT1; 5HTTLLR; OPRM1; and GABRA3. At 432 days post Suboxone® withdrawal the patient is being maintained on KB220Z, has been urine tested and is opioid free. Genotyping data revealed a moderate genetic risk for addiction showing a hypodopaminergic trait. This preliminary case data suggest that the daily use of KB220Z could provide a cost effective alternative substitution adjunctive modality for Suboxone®. We encourage double-blind randomized -placebo controlled studies to test the proposition that KB220Z may act as a putative natural opioid substitution maintenance adjunct.

Fentanyl Buccal Tablet for the Treatment of Breakthrough Pain: Pharmacokinetics of Buccal Mucosa Delivery and Clinical Efficacy

PubMed Central

Darwish, Mona; Hamed, Ehab; Messina, John

2010-01-01

The treatment of breakthrough pain (BTP), a transitory exacerbation of pain that occurs on a background of otherwise-controlled, persistent pain, requires an opioid formulation and/or method of administration that can provide rapid and extensive systemic exposure. Fentanyl buccal tablet (FBT; FENTORA®, Cephalon, Inc.) employs OraVescent® drug delivery technology, which enhances the rate and extent of fentanyl absorption. OraVescent technology enhances the oral dissolution and buccal absorption of fentanyl, which facilitates rapid uptake of fentanyl into the bloodstream, reducing gastrointestinal absorption and minimizing extensive first-pass metabolism. The resulting pharmacokinetic profile of FBT is characterized by greater bioavailability and a higher early systemic exposure compared with the earlier oral transmucosal fentanyl citrate formulation. In clinical studies of opioid-tolerant patients with cancer-related and noncancer-related BTP, FBT has provided consistent and clinically relevant improvements in pain intensity and pain relief relative to placebo, with a safety and tolerability profile that is generally typical of that observed with other potent opioids. The pharmacokinetic properties of FBT allow for meaningful clinical efficacy, with an onset of action that closely matches the onset of BTP. PMID:20634985

42 CFR 8.21 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-10-01

... PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID... Adverse Action Regarding Withdrawal of Approval of an Accreditation Body § 8.21 Applicability. The... body of an adverse action taken regarding withdrawal of approval of the accreditation body under the...

42 CFR 8.21 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-10-01

... PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID... Adverse Action Regarding Withdrawal of Approval of an Accreditation Body § 8.21 Applicability. The... body of an adverse action taken regarding withdrawal of approval of the accreditation body under the...

Distinct Mu, Delta, and Kappa Opioid Receptor Mechanisms Underlie Low Sociability and Depressive-Like Behaviors During Heroin Abstinence

PubMed Central

Lutz, Pierre-Eric; Ayranci, Gulebru; Chu-Sin-Chung, Paul; Matifas, Audrey; Koebel, Pascale; Filliol, Dominique; Befort, Katia; Ouagazzal, Abdel-Mouttalib; Kieffer, Brigitte L

2014-01-01

Addiction is a chronic disorder involving recurring intoxication, withdrawal, and craving episodes. Escaping this vicious cycle requires maintenance of abstinence for extended periods of time and is a true challenge for addicted individuals. The emergence of depressive symptoms, including social withdrawal, is considered a main cause for relapse, but underlying mechanisms are poorly understood. Here we establish a mouse model of protracted abstinence to heroin, a major abused opiate, where both emotional and working memory deficits unfold. We show that delta and kappa opioid receptor (DOR and KOR, respectively) knockout mice develop either stronger or reduced emotional disruption during heroin abstinence, establishing DOR and KOR activities as protective and vulnerability factors, respectively, that regulate the severity of abstinence. Further, we found that chronic treatment with the antidepressant drug fluoxetine prevents emergence of low sociability, with no impact on the working memory deficit, implicating serotonergic mechanisms predominantly in emotional aspects of abstinence symptoms. Finally, targeting the main serotonergic brain structure, we show that gene knockout of mu opioid receptors (MORs) in the dorsal raphe nucleus (DRN) before heroin exposure abolishes the development of social withdrawal. This is the first result demonstrating that intermittent chronic MOR activation at the level of DRN represents an essential mechanism contributing to low sociability during protracted heroin abstinence. Altogether, our findings reveal crucial and distinct roles for all three opioid receptors in the development of emotional alterations that follow a history of heroin exposure and open the way towards understanding opioid system-mediated serotonin homeostasis in heroin abuse. PMID:24874714

Gender differences in pharmacokinetics and pharmacodynamics of methadone substitution therapy.

PubMed

Graziani, Manuela; Nisticò, Robert

2015-01-01

Gender-related differences in the pharmacological effects of drug are an emerging topic. This review examines gender differences in both pharmacokinetic and pharmacodynamic aspects of methadone, a long-acting opioid agonist that is prescribed as a treatment for opioid dependence and the management of chronic pain. We performed a search in the Medline database from 1990 to 2014 in order to find published literature related to gender differences in pharmacokinetics (PK) and pharmacodynamics (PD) of methadone. None of the studies were carried out with the primary or secondary aim to identify any gender differences in the pharmacokinetic profile of methadone. Importantly; high inter-subjects variability in PK parameters was found also intra female population. The reported differences in volume of distribution could be ascribed to the physiological differences between men and women in body weight and composition, taking into account that the dose of methadone was established irrespective of body weight of patients (Peles and Adelson, 2006). On the other hand, the few studies present in literature found no gender difference in some direct pharmacodynamic parameters. Some reports have suggested that female gender is associated with an increased risk for long-QT-related cardiac arrhythmias in methadone maintenance subjects. Even though it may be too simplistic to expect variability only in one parameter to explain inter-individual variation in methadone response, we believe that a better knowledge of gender-related differences might have significant implications for better outcomes in opioid dependence substitution therapy in women.

The CLOSED trial; CLOnidine compared with midazolam for SEDation of paediatric patients in the intensive care unit: study protocol for a multicentre randomised controlled trial.

PubMed

Neubert, Antje; Baarslag, Manuel Alberto; Dijk, Monique van; Rosmalen, Joost van; Standing, Joseph F; Sheng, Yucheng; Rascher, Wolfgang; Roberts, Deborah; Winslade, Jackie; Rawcliffe, Louise; Hanning, Sara M; Metsvaht, Tuuli; Giannuzzi, Viviana; Larsson, Peter; Pokorná, Pavla; Simonetti, Alessandra; Tibboel, Dick

2017-06-21

Sedation is an essential part of paediatric critical care. Midazolam, often in combination with opioids, is the current gold standard drug. However, as it is a far-from-ideal agent, clonidine is increasingly being used in children. This drug is prescribed off-label for this indication, as many drugs in paediatrics are. Therefore, the CLOSED trial aims to provide data on the pharmacokinetics, safety and efficacy of clonidine for the sedation of mechanically ventilated patients in order to obtain a paediatric-use marketing authorisation. The CLOSED study is a multicentre, double-blind, randomised, active-controlled non-inferiority trial with a 1:1 randomisation between clonidine and midazolam. Both treatment groups are stratified according to age in three groups with the same size: <28 days (n=100), 28 days to <2 years (n=100) and 2-18 years (n=100). The primary end point is defined as the occurrence of sedation failure within the study period. Secondary end points include a pharmacokinetic/pharmacodynamic relationship, pharmacogenetics, occurrence of delirium and withdrawal syndrome, opioid consumption and neurodevelopment in the neonatal age group. Logistic regression will be used for the primary end point, appropriate statistics will be used for the secondary end points. Written informed consent will be obtained from the parents/caregivers. Verbal or deferred consent will be used in the sites where national legislation allows. The study has institutional review board approval at recruiting sites. The results will be published in a peer-reviewed journal and shared with the worldwide medical community. EudraCT: 2014-003582-24; Clinicaltrials.gov: NCT02509273; pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Informed consent to opioid agonist maintenance treatment: recommended ethical guidelines.

PubMed

Carter, Adrian; Hall, Wayne

2008-02-01

Some bioethicists have questioned whether opioid addicted individuals are able to provide free and informed consent to opioid agonist maintenance treatment. Conflicting motives for providing such treatment (e.g. improving the personal health of addicts and protecting public health and order) can also influence what individuals are required to consent to, and how that consent is obtained. We discuss both issues and attempt to specify the conditions for obtaining informed consent to agonist maintenance treatment for opioid addiction. We briefly review the neuroscientific literature on the effects of addiction on the autonomy and decision-making capacity of opioid dependent individuals, and ascertain how informed consent to the treatment of opioid addiction should be obtained. We also provide an ethical analysis of the competing social and medical forces that influence the consent process and make some recommendations on how to ensure that individuals enter maintenance treatment that is provided in an effective and ethical way. Our analysis shows that whilst the autonomy of opioid dependent individuals is impaired by their addiction, they do retain the ability to consent to treatment provided they are not in acute withdrawal or intoxication. These symptoms should have abated, either by supervised withdrawal or stabilisation on agonist maintenance, before they are asked to consent to a detailed treatment contract. Once stabilised, individuals should be provided with detailed information about the risks and benefits of all treatments, and restrictions and regulations under which they are provided. Informed consent is an important part of the treatment process that should be obtained in ways that increase the autonomy and decision-making capacity in opioid addicts.

The New Kid on the Block--Incorporating Buprenorphine into a Medical Toxicology Practice.

PubMed

Wiegand, Timothy J

2016-03-01

Buprenorphine represents a safe and effective therapy for treating opioid dependence, alleviating craving and withdrawal symptoms in opioid-dependent patients. Buprenorphine has a "blocking" effect against the action of other opioids at the mu-receptor, preventing not only opioid-induced euphoria, but CNS and respiratory depressant effects as well. Buprenorphine was approved for the treatment of opioid dependence in 2002 after the passage of Drug Abuse Treatment Act 2000 (DATA 2000) which allowed clinicians to treat opioid-dependent patients with specifically named opioid agonist therapies in an office setting. Buprenorphine programs reduce the prevalence of HIV and hepatitis C and reduce criminal behaviors associated with illicit drug use. Patients stabilized on buprenorphine have increased employment, enhanced engagement with social services, and better overall health and well-being.

The challenge of perioperative pain management in opioid-tolerant patients

PubMed Central

Coluzzi, Flaminia; Bifulco, Francesca; Cuomo, Arturo; Dauri, Mario; Leonardi, Claudio; Melotti, Rita Maria; Natoli, Silvia; Romualdi, Patrizia; Savoia, Gennaro; Corcione, Antonio

2017-01-01

The increasing number of opioid users among chronic pain patients, and opioid abusers among the general population, makes perioperative pain management challenging for health care professionals. Anesthesiologists, surgeons, and nurses should be familiar with some pharmacological phenomena which are typical of opioid users and abusers, such as tolerance, physical dependence, hyperalgesia, and addiction. Inadequate pain management is very common in these patients, due to common prejudices and fears. The target of preoperative evaluation is to identify comorbidities and risk factors and recognize signs and symptoms of opioid abuse and opioid withdrawal. Clinicians are encouraged to plan perioperative pain medications and to refer these patients to psychiatrists and addiction specialists for their evaluation. The aim of this review was to give practical suggestions for perioperative management of surgical opioid-tolerant patients, together with schemes of opioid conversion for chronic pain patients assuming oral or transdermal opioids, and patients under maintenance programs with methadone, buprenorphine, or naltrexone. PMID:28919771

Population Genetic-Based Pharmacokinetic Modeling of Methadone and its Relationship with the QTc Interval in Opioid-Dependent Patients.

PubMed

Csajka, Chantal; Crettol, Séverine; Guidi, Monia; Eap, Chin B

2016-12-01

Methadone is a μ-opioid agonist widely used for the treatment of pain, and for detoxification or maintenance treatment in opioid addiction. It has been shown to exhibit large pharmacokinetic variability and concentration-QTc relationships. In this study we investigated the relative influence of genetic polymorphism and other variables on the dose concentration-QTc relationship. A population model for methadone enantiomers in 251 opioid-dependent patients was developed using non-linear mixed effect modeling (NONMEM ® ). Various models were tested to characterize the pharmacokinetics of (R)- and (S)-methadone and the pharmacokinetic-pharmacodynamic relationship, while including demographics, physiological conditions, co-medications, and genetic variants as covariates. Model-based simulations were performed to assess the relative increase in QTc with dose upon stratification according to genetic polymorphisms involved in methadone disposition. A two-compartment model with first-order absorption and lag time provided the best model fit for (R)- and (S)-methadone pharmacokinetics. (S)-methadone clearance was influenced by cytochrome P450 (CYP) 2B6 activity, ABCB1 3435C>T, and α-1 acid glycoprotein level, while (R)-methadone clearance was influenced by CYP2B6 activity, POR*28, and CYP3A4*22. A linear model described the methadone concentration-QTc relationship, with a mean QTc increase of 9.9 ms and 19.2 ms per 1000 ng/ml of (R)- and (S)-methadone, respectively. Simulations with different methadone doses up to 240 mg/day showed that <8 % of patients presented with a QTc interval above 450 ms; however, this might reach 12 to 18 % for (R)- and (S)-methadone, respectively, in patients with a genetic status associated with a decreased methadone elimination at doses exceeding 240 mg/day. Risk factor assessment, electrocardiogram monitoring, and therapeutic drug monitoring are beneficial to optimize treatment in methadone patients, especially for those who have low levels despite high methadone doses, or who are at risk of overdosing.

Pharmacological prevention of rocuronium-induced injection pain or withdrawal movements: a meta-analysis.

PubMed

Kwak, Hyun Jeong; Kim, Ji Young; Kim, Yong Beom; Min, Sang Kee; Moon, Bong Ki; Kim, Jong Yeop

2013-10-01

Rocuronium is reported to be associated with injection pain or withdrawal movement (IPWM). This meta-analysis assessed the efficacy of different pharmacological treatments used to decrease the incidence of the rocuronium-induced IPWM. We searched the Cochrane Library, Embase and PubMed for randomized controlled trials comparing a pharmacological drug with a placebo to prevent the rocuronium-induced IPWM and found 37 studies with 5,595 patients. Overall incidence of rocuronium-induced IPWM was 74%. Pretreatment with opioids [risk ratio (RR) 0.16; 95% confidence interval (95% CI) 0.09-0.29], lidocaine (0.47; 0.35-0.64), and ketamine (0.41; 0.22-0.77) were effective in decreasing IPWM. Lidocaine pretreatment with venous occlusion (0.40; 0.32-0.49) and opioids pretreatment with venous occlusion (0.77; 0.61-0.96) were also effective. Mixing sodium bicarbonate (NaHCO3) with rocuronium (0.15; 0.06-0.34) was also efficacious in reducing IPWM. Indirect comparison shows that the RR of NaHCO3 admixture and pretreatment with opioids were lower than that of the other four interventions (pretreatments of ketamine or lidocaine, and lidocaine or opioids with venous occlusion). This meta-analysis suggests that opioids, lidocaine, ketamine, and NaHCO3 are effective in decreasing rocuronium-induced IPWM. Considering the efficacy and convenience, pretreatment with opioids without venous occlusion is recommended for reducing rocuronium-induced IPWM.

Dose-adjusted plasma concentrations of sublingual buprenorphine are lower during than after pregnancy.

PubMed

Bastian, Jaime R; Chen, Huijun; Zhang, Hongfei; Rothenberger, Scott; Tarter, Ralph; English, Dennis; Venkataramanan, Raman; Caritis, Steve N

2017-01-01

Buprenorphine is a Food and Drug Administration-approved maintenance therapy for opioid use disorders and is increasingly being used in pregnant women with opioid use disorders as an alternative to methadone. Dosing of buprenorphine in pregnant women is based on the regimen recommended for nonpregnant females and males. Limited data are available defining the pharmacokinetic properties of sublingual buprenorphine administered during pregnancy. This study evaluated the impact of physiological changes associated with pregnancy on the pharmacokinetics of sublingual buprenorphine during and after pregnancy. Pregnant women (n = 13), between 18 0/7 and 37 6/7 weeks' singleton gestation, receiving sublingual buprenorphine twice daily for opioid use disorders were studied. Pharmacokinetic-2 studies were performed between 18 and 25 weeks (n = 7), pharmacokinetic-3 studies were performed between 31 and 37 weeks (n = 11), and pharmacokinetic-P was performed 4-18 weeks postpartum (n = 10). On the day of the study, blood was withdrawn prior to the daily morning dose of buprenorphine and at 0.25, 0.5, 0.75, 1, 1.5, 2, 4, 8, and 12 hours after the dose. Buprenorphine plasma concentrations were analyzed by liquid chromatography tandem mass spectrometric detection. All pharmacokinetic parameters were observed or estimated using Microsoft Excel. Statistical analyses were performed to identify significant changes in study participants' buprenorphine pharmacokinetic parameter estimates over the duration of the study. Univariate linear and generalized linear mixed models were used to investigate changes in these measures over time, some of which were log transformed for normality. Dose-normalized (plasma concentration per dose) buprenorphine plasma concentrations were significantly lower during pregnancy (pharmacokinetic-2 plus pharmacokinetic-3) than during the postpartum period (pharmacokinetic-P). Specific pharmacokinetic parameters (and level of significance) were as follows: the area under the buprenorphine plasma concentration-time curves (P < .003), maximum buprenorphine concentrations (P < .018), buprenorphine concentrations at 0 hour (P < .002), and buprenorphine concentrations at 12 hours (P < .001). None of these parameters differed significantly during pregnancy (ie, pharmacokinetic-2 vs pharmacokinetic-3). The time to maximum buprenorphine concentrations did not differ significantly between groups. The dose-normalized plasma concentrations during a dosing interval and the overall exposure of buprenorphine (area under the buprenorphine plasma concentration-time curves) are lower throughout pregnancy compared with the postpartum period. This indicates an increase in apparent clearance of buprenorphine during pregnancy. These data suggest that pregnant women may need a higher dose of sublingual buprenorphine compared with postpartum individuals. The dose of buprenorphine should be assessed after delivery to maintain similar buprenorphine exposure during the postpartum period. Copyright © 2016 Elsevier Inc. All rights reserved.

“I Just Wanted to Tell You That Loperamide WILL WORK”: A Web-Based Study of Extra-Medical Use of Loperamide

PubMed Central

Daniulaityte, Raminta; Carlson, Robert; Falck, Russel; Cameron, Delroy; Perera, Sujan; Chen, Lu; Sheth, Amit

2013-01-01

Aims Many websites provide a means for individuals to share their experiences and knowledge about different drugs. Such User-Generated Content (UGC) can be a rich data source to study emerging drug use practices and trends. This study examined UGC on extra-medical use of loperamide among illicit opioid users. Methods A website that allows for the free discussion of illicit drugs and is accessible for public viewing was selected for analysis. Web-forum posts were retrieved using web crawlers and retained in a local text database. The database was queried to extract posts with a mention of loperamide and relevant brand/slang terms. Over 1,290 posts were identified. A random sample of 258 posts was coded using NVivo to identify intent, dosage, and side-effects of loperamide use. Results There has been an increase in discussions related to loperamide’s use by non-medical opioid users, especially in 2010–2011. Loperamide was primarily discussed as a remedy to alleviate a broad range of opioid withdrawal symptoms, and was sometimes referred to as “poor man’s” methadone. Typical doses ranged 70–100 mg per day, much higher than an indicated daily dose of 16 mg. Conclusions This study suggests that loperamide is being used extra-medically to self-treat opioid withdrawal symptoms. There is a growing demand among people who are opioid dependent for drugs to control withdrawal symptoms, and loperamide appears to fit that role. The study also highlights the potential of the Web as a “leading edge” data source in identifying emerging drug use practices. PMID:23201175

"I just wanted to tell you that loperamide WILL WORK": a web-based study of extra-medical use of loperamide.

PubMed

Daniulaityte, Raminta; Carlson, Robert; Falck, Russel; Cameron, Delroy; Perera, Sujan; Chen, Lu; Sheth, Amit

2013-06-01

Many websites provide a means for individuals to share their experiences and knowledge about different drugs. Such User-Generated Content (UGC) can be a rich data source to study emerging drug use practices and trends. This study examined UGC on extra-medical use of loperamide among illicit opioid users. A website that allows for the free discussion of illicit drugs and is accessible for public viewing was selected for analysis. Web-forum posts were retrieved using web crawlers and retained in a local text database. The database was queried to extract posts with a mention of loperamide and relevant brand/slang terms. Over 1290 posts were identified. A random sample of 258 posts was coded using NVivo to identify intent, dosage, and side-effects of loperamide use. There has been an increase in discussions related to loperamide's use by non-medical opioid users, especially in 2010-2011 Loperamide was primarily discussed as a remedy to alleviate a broad range of opioid withdrawal symptoms, and was sometimes referred to as "poor man's" methadone. Typical doses ranged 70-100mg per day, much higher than an indicated daily dose of 16mg. This study suggests that loperamide is being used extra-medically to self-treat opioid withdrawal symptoms. There is a growing demand among people who are opioid dependent for drugs to control withdrawal symptoms, and loperamide appears to fit that role. The study also highlights the potential of the Web as a "leading edge" data source in identifying emerging drug use practices. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Preliminary buprenorphine sublingual tablet pharmacokinetic data in plasma, oral fluid and sweat during treatment of opioid-dependent pregnant women

PubMed Central

Concheiro, Marta; Jones, Hendreé E.; Johnson, Rolley E.; Choo, Robin; Huestis, Marilyn A.

2011-01-01

Background Buprenorphine is currently under investigation as a pharmacotherapy to treat pregnant women for opioid dependence. This research evaluates buprenorphine (BUP), norbuprenophine (NBUP), buprenorphine-glucuronide (BUP-Gluc) and norbuprenorphine-glucuronide (NBUP-Gluc) pharmacokinetics after high dose (14–20 mg) BUP sublingual tablet administration in three opioid-dependent pregnant women. Methods Oral fluid and sweat specimens were collected in addition to plasma specimens for 24 h during gestation weeks 28 or 29 and 34, and 2 months after delivery. Tmax was not affected by pregnancy; however, BUP and NBUP Cmax and AUC0–24h tended to be lower during pregnancy compared to postpartum levels. Results Statistically significant but weak positive correlations were found for BUP plasma and OF concentrations, and BUP/NBUP ratios in plasma and OF. Conclusion Statistically significant negative correlations were observed for times of specimen collection and BUP and NBUP OF/plasma ratios. BUP-Gluc and NBUP-Gluc were detected in only 5% of OF specimens. In sweat, BUP and NBUP were detected in only 4 of 25 (12 or 24 h) specimens in low concentrations (<2.4 ng/patch). These preliminary data describe BUP and metabolite pharmacokinetics in pregnant women and suggest that, like methadone, upward dose adjustments may be needed with advancing gestation. PMID:21860340

Inhibitory effect of bacopasides on spontaneous morphine withdrawal induced depression in mice.

PubMed

Rauf, Khalid; Subhan, Fazal; Abbas, Muzaffar; Ali, Syed Mobasher; Ali, Gowhar; Ashfaq, Muhammad; Abbas, Ghulam

2014-06-01

Bacopa monnieri is a perennial herb with a world known image as a nootropic. We investigated the effect of Bacopa monnieri methanolic extract (Mt Ext BM) 10, 20, and 30 mg/kg body weight (b.w) on acquisition and expression of morphine withdrawal induced depression in mice. Locally available Bacopa monnieri (BM) was screened for contents of Bacoside A3, Bacopasaponin C, and Bacopaside II using HPLC with UV. Morphine dependence was induced in mice using twice daily escalating chronic morphine treatments (20-65 mg/kg b.w) for eight consecutive days. Morphine withdrawal induced depression was assayed in animals using forced swimming test (FST), three days after last morphine injection. The HPLC analysis revealed that Mt-ext BM contained Bacoside A3 as major component, i.e. 4 µg in each mg of extract. The chronic treatment with Met Ext BM 10, 20, and 30 mg/kg b.w. dosing significantly inhibited opioid withdrawal induced depression in mice. These findings imply a newer potential role of Bacopa monnieri in the clinical management of opioid withdrawal induced depression which can be attributed to Bacoside A3. Copyright © 2013 John Wiley & Sons, Ltd.

Mu-opioid receptor redistribution in the locus coeruleus upon precipitation of withdrawal in opiate-dependent rats.

PubMed

Scavone, Jillian L; Van Bockstaele, Elisabeth J

2009-03-01

Administration of mu-opioid receptor (MOR) agonists is known to produce adaptive changes within noradrenergic neurons of the rat locus coeruleus (LC). Alterations in the subcellular distribution of MOR have been shown to occur in the LC in response to full agonists and endogenous peptides; however, there is considerable debate in the literature whether trafficking of MOR occurs after chronic exposure to the partial-agonist morphine. In the present study, we examined adaptations in MOR after chronic opioid exposure using immunofluorescence and electron microscopy (EM), using receptor internalization as a functional endpoint. MOR trafficking in LC neurons was characterized in morphine-dependent rats that were given naltrexone at a dose known to precipitate withdrawal. After chronic morphine exposure, a subtle redistribution of MOR immunoreactivity from the membrane to the cytosol was detected within dendrites of LC neurons. Interestingly, an acute injection of naltrexone in rats exposed to chronic morphine produced a robust internalization of MOR, whereas administration of naltrexone failed to do so in naïve animals. These findings provide anatomical evidence for modified regulation of MOR trafficking after chronic morphine treatment in brain noradrenergic neurons. Adaptations in the MOR signaling pathways that regulate internalization may occur as a consequence of chronic treatment and precipitation of withdrawal. Mechanisms underlying this effect might include differential MOR regulation in the LC, or downstream effects of withdrawal-induced enkephalin (ENK) release from afferents to the LC. (c) 2009 Wiley-Liss, Inc.

Persistent Pain Maintains Morphine-Seeking Behavior after Morphine Withdrawal through Reduced MeCP2 Repression of Glua1 in Rat Central Amygdala

PubMed Central

Hou, Yuan-Yuan; Cai, You-Qing

2015-01-01

As long-term opioids are increasingly used for control of chronic pain, how pain affects the rewarding effect of opioids and hence risk of prescription opioid misuse and abuse remains a healthcare concern and a challenging issue in current pain management. In this study, using a rat model of morphine self-administration, we investigated the molecular mechanisms underlying the impact of pain on operant behavior of morphine intake and morphine seeking before and after morphine withdrawal. We found that rats with persistent pain consumed a similar amount of daily morphine to that in control rats without pain, but maintained their level-pressing behavior of morphine seeking after abstinence of morphine at 0.2 mg/kg, whereas this behavior was gradually diminished in control rats. In the central nucleus of amygdala (CeA), a limbic structure critically involved in the affective dimension of pain, proteins of GluA1 subunits of glutamate AMPA receptors were upregulated during morphine withdrawal, and viral knockdown of CeA GluA1 eliminated the morphine-seeking behavior in withdrawn rats of the pain group. Chromatin immunoprecipitation analysis revealed that the methyl CpG-binding protein 2 (MeCP2) was enriched in the promoter region of Gria1 encoding GluA1 and this enrichment was significantly attenuated in withdrawn rats of the pain group. Furthermore, viral overexpression of CeA MeCP2 repressed the GluA1 level and eliminated the maintenance of morphine-seeking behavior after morphine withdrawal. These results suggest direct MeCp2 repression of GluA1 function as a likely mechanism for morphine-seeking behavior maintained by long-lasting affective pain after morphine withdrawal. PMID:25716866

Concurrent Validation of the Clinical Opiate Withdrawal Scale (COWS) and Single-Item Indices against the Clinical Institute Narcotic Assessment (CINA) Opioid Withdrawal Instrument

PubMed Central

Tompkins, D. Andrew; Bigelow, George E.; Harrison, Joseph A.; Johnson, Rolley E.; Fudala, Paul J.; Strain, Eric C.

2009-01-01

Introduction The Clinical Opiate Withdrawal Scale (COWS) is an 11-item clinician-administered scale assessing opioid withdrawal. Though commonly used in clinical practice, it has not been systematically validated. The present study validated the COWS in comparison to the validated Clinical Institute Narcotic Assessment (CINA) scale. Method Opioid-dependent volunteers were enrolled in a residential trial and stabilized on morphine 30 mg given subcutaneously four times daily. Subjects then underwent double-blind, randomized challenges of intramuscularly administered placebo and naloxone (0.4 mg) on separate days, during which the COWS, CINA, and visual analog scale (VAS) assessments were concurrently obtained. Subjects completing both challenges were included (N=46). Correlations between mean peak COWS and CINA scores as well as self-report VAS questions were calculated. Results Mean peak COWS and CINA scores of 7.6 and 24.4, respectively, occurred on average 30 minutes post-injection of naloxone. Mean COWS and CINA scores 30 minutes after placebo injection were 1.3 and 18.9, respectively. The Pearson correlation coefficient for peak COWS and CINA scores during the naloxone challenge session was 0.85 (p<0.001). Peak COWS scores also correlated well with peak VAS self-report scores of bad drug effect (r=0.57, p<0.001) and feeling sick (r=0.57, p<0.001), providing additional evidence of concurrent validity. Placebo was not associated with any significant elevation of COWS, CINA, or VAS scores, indicating discriminant validity. Cronbach’s alpha for the COWS was 0.78, indicating good internal consistency (reliability). Discussion COWS, CINA, and certain VAS items are all valid measurement tools for acute opiate withdrawal. PMID:19647958

Treatment of opioid use disorder with ibogaine: detoxification and drug use outcomes.

PubMed

Brown, Thomas Kingsley; Alper, Kenneth

2018-01-01

Ibogaine is a monoterpene indole alkaloid used in medical and nonmedical settings for the treatment of opioid use disorder. Its mechanism of action is apparently novel. There are no published prospective studies of drug use outcomes with ibogaine. To study outcomes following opioid detoxification with ibogaine. In this observational study, 30 subjects with DSM-IV Opioid Dependence (25 males, 5 females) received a mean total dose of 1,540 ± 920 mg ibogaine HCl. Subjects used oxycodone (n = 21; 70%) and/or heroin (n = 18; 60%) in respective amounts of 250 ± 180 mg/day and 1.3 ± 0.94 g/day, and averaged 3.1 ± 2.6 previous episodes of treatment for opioid dependence. Detoxification and follow-up outcomes at 1, 3, 6, 9, and 12 months were evaluated utilizing the Subjective Opioid Withdrawal Scale (SOWS) and Addiction Severity Index Composite (ASIC) scores, respectively. SOWS scores decreased from 31.0 ± 11.6 pretreatment to 14.0 ± 9.8 at 76.5 ± 30 hours posttreatment (t = 7.07, df = 26, p < 0.001). At 1-month posttreatment follow-up, 15 subjects (50%) reported no opioid use during the previous 30 days. ASIC Drug Use and Legal and Family/Social Status scores were improved relative to pretreatment baseline at all posttreatment time points (p < .001). Improvement in Drug Use scores was maximal at 1 month, and subsequently sustained from 3 to 12 months at levels that did not reach equivalence to the effect at 1 month. Ibogaine was associated with substantive effects on opioid withdrawal symptoms and drug use in subjects for whom other treatments had been unsuccessful, and may provide a useful prototype for discovery and development of innovative pharmacotherapy of addiction.

Within- and between- subject variability in methadone pharmacokinetics and pharmacodynamics in methadone maintenance subjects

PubMed Central

Hanna, Julia; Foster, David JR; Salter, Amy; Somogyi, Andrew A; White, Jason M; Bochner, Felix

2005-01-01

Aims To investigate within- and between-subject variability of the pharmacodynamics and pharmacokinetics of (R)- and (S)-methadone in methadone maintenance subjects at steady-state. Methods Six non-holder subjects were studied on three occasions at 7–16 day intervals; doses (20–170 mg/day) remained unchanged. Blood samples and pharmacodynamic data were collected 10–12 times over a 24-h inter-dosing interval. All pharmacodynamic data were expressed as the area under the end-point versus time curve. Using analyses of variance with mixed effects, best estimates were made of the ratio of between- to within-subject variation, with corresponding 95% confidence intervals (CI) for within-subject variation at the average value. Results Subjects were relatively consistent between occasions, whereas there was much greater between-subject variability (P < 0.02) for all measures. Estimates of the ratio of between- to within-subject variation ranged from 2.2–12.8 for pharmacodynamic measures, and 1.3–7.9 for pharmacokinetic parameters. For pain, total mood disturbance, withdrawal, pupil size and respiration rate, 95% CI for within-subject measures ranged ≤2-fold, while this was greater for subjective direct opioid effects (4.2-fold). For CL/F of the active (R)-methadone, the variance ratio was 4.9 (P < 0.0003), with 95% CI for within-subject measures ranging ≤2-fold. (S)-methadone CL/F demonstrated greater within-subject variability (3.4-fold), possibly contributing to a smaller (2.7; P < 0.0003) ratio of between- to within-subject variance. Conclusions Non-holder methadone maintenance treatment participants appear to respond consistently with respect to pharmacokinetics and pharmacodynamics over a 1–2 month period. Such knowledge may help prescribers to determine whether alternative dosing regimens or treatments might be more appropriate in this population. PMID:16187972

The endogenous opioid system in cocaine addiction: what lessons have opioid peptide and receptor knockout mice taught us?

PubMed Central

Yoo, Ji Hoon; Kitchen, Ian; Bailey, Alexis

2012-01-01

Cocaine addiction has become a major concern in the UK as Britain tops the European ‘league table’ for cocaine abuse. Despite its devastating health and socio-economic consequences, no effective pharmacotherapy for treating cocaine addiction is available. Identifying neurochemical changes induced by repeated drug exposure is critical not only for understanding the transition from recreational drug use towards compulsive drug abuse but also for the development of novel targets for the treatment of the disease and especially for relapse prevention. This article focuses on the effects of chronic cocaine exposure and withdrawal on each of the endogenous opioid peptides and receptors in rodent models. In addition, we review the studies that utilized opioid peptide or receptor knockout mice in order to identify and/or clarify the role of different components of the opioid system in cocaine-addictive behaviours and in cocaine-induced alterations of brain neurochemistry. The review of these studies indicates a region-specific activation of the µ-opioid receptor system following chronic cocaine exposure, which may contribute towards the rewarding effect of the drug and possibly towards cocaine craving during withdrawal followed by relapse. Cocaine also causes a region-specific activation of the κ-opioid receptor/dynorphin system, which may antagonize the rewarding effect of the drug, and at the same time, contribute to the stress-inducing properties of the drug and the triggering of relapse. These conclusions have important implications for the development of effective pharmacotherapy for the treatment of cocaine addiction and the prevention of relapse. PMID:22428846

Discriminative Stimulus Effects of Tramadol in Humans

PubMed Central

Duke, Angela N.; Bigelow, George E.; Lanier, Ryan K.

2011-01-01

Tramadol is an unscheduled atypical analgesic that acts as an agonist at μ-opioid receptors and inhibits monoamine reuptake. Tramadol can suppress opioid withdrawal, and chronic administration can produce opioid physical dependence; however, diversion and abuse of tramadol is low. The present study further characterized tramadol in a three-choice discrimination procedure. Nondependent volunteers with active stimulant and opioid use (n = 8) participated in this residential laboratory study. Subjects were trained to discriminate between placebo, hydromorphone (8 mg), and methylphenidate (60 mg), and tests of acquisition confirmed that all volunteers could discriminate between the training drugs. The following drug conditions were then tested during discrimination test sessions: placebo, hydromorphone (4 and 8 mg), methylphenidate (30 and 60 mg), and tramadol (50, 100, 200, and 400 mg). In addition to discrimination measures, which included discrete choice, point distribution, and operant responding, subjective and physiological effects were measured for each test condition. Both doses of hydromorphone and methylphenidate were identified as hydromorphone- and methylphenidate-like, respectively. Lower doses of tramadol were generally identified as placebo, with higher doses (200 and 400 mg) identified as hydromorphone, or opioid-like. The highest dose of tramadol increased ratings on the stimulant scale, but was not significantly identified as methylphenidate-like. Tramadol did not significantly increase subjective ratings associated with reinforcement. Taken together, these results extend previous work with tramadol as a potential medication for the treatment of opioid dependence and withdrawal, showing acute doses of tramadol exhibit a profile of effects similar to opioid agonists and may have abuse liability in certain populations. PMID:21467190

Role of mu-opioids as cofactors in human immunodeficiency virus type 1 disease progression and neuropathogenesis

PubMed Central

Banerjee, Anupam; Strazza, Marianne; Wigdahl, Brian; Pirrone, Vanessa; Meucci, Olimpia

2013-01-01

About one third of acquired immunodeficiency syndrome cases in the USA have been attributed to the use of injected addictive drugs, frequently involving opioids like heroin and morphine, establishing them as significant predisposing risk factors for contracting human immuno-deficiency virus type 1 (HIV-1). Accumulating evidence from in vitro and in vivo experimental systems indicates that opioids act in concert with HIV-1 proteins to exacerbate dysregulation of neural and immune cell function and survival through diverse molecular mechanisms. In contrast, the impact of opioid exposure and withdrawal on the viral life cycle and HIV-1 disease progression itself is unclear, with conflicting reports emerging from the simian immunodeficiency virus and simian–human immunodeficiency virus infection models. However, these studies suggest a potential role of opioids in elevated viral production. Because human microglia, astrocytes, CD4+ T lymphocytes, and monocyte-derived macrophages express opioid receptors, it is likely that intracellular signaling events triggered by morphine facilitate enhancement of HIV-1 infection in these target cell populations. This review highlights the biochemical changes that accompany prolonged exposure to and withdrawal from morphine that synergize with HIV-1 proteins to disrupt normal cellular physiological functions especially within the central nervous system. More importantly, it collates evidence from epidemiological studies, animal models, and heterologous cell systems to propose a mechanistic link between such physiological adaptations and direct modulation of HIV-1 production. Understanding the opioid–HIV-1 interface at the molecular level is vitally important in designing better treatment strategies for HIV-1-infected patients who abuse opioids. PMID:21735315

A test of the opponent-process theory of motivation using lesions that selectively block morphine reward.

PubMed

Vargas-Perez, Hector; Ting-A-Kee, Ryan A; Heinmiller, Andrew; Sturgess, Jessica E; van der Kooy, Derek

2007-06-01

The opponent-process theory of motivation postulates that motivational stimuli activate a rewarding process that is followed by an opposed aversive process in a homeostatic control mechanism. Thus, an acute injection of morphine in nondependent animals should evoke an acute rewarding response, followed by a later aversive response. Indeed, the tegmental pedunculopontine nucleus (TPP) mediates the rewarding effects of opiates in previously morphine-naive animals, but not other unconditioned effects of opiates, or learning ability. The aversive opponent process for acute morphine reward was revealed using a place-conditioning paradigm. The conditioned place aversion induced by 16-h spontaneous morphine withdrawal from an acute morphine injection in nondependent rats was abolished by TPP lesions performed prior to drug experience. However, TPP-lesioned rats did show conditioned aversions for an environment paired with the acute administration of the opioid antagonist naloxone, which blocks endogenous opioids. The results show that blocking the rewarding effects of morphine with TPP lesions also blocked the opponent aversive effects of acute morphine withdrawal in nondependent animals. Thus, this spontaneous withdrawal aversion (the opponent process) is induced by the acute rewarding effects of morphine and not by other unconditioned effects of morphine, the pharmacological effects of morphine or endogenous opioids being displaced from opiate receptors.

Pharmacokinetics of ammonium sulfate gradient loaded liposome-encapsulated oxymorphone and hydromorphone in healthy dogs

PubMed Central

Smith, Lesley J.; Kukanich, Butch K.; Krugner-Higby, Lisa A.; Schmidt, Brynn H.; Heath, Timothy D.

2013-01-01

Objective To evaluate the pharmacokinetics, in dogs, of liposome-encapsulated oxymorphone and hydromorphone made by the ammonium sulfate gradient loading technique (ASG). Animals Four healthy purpose-bred Beagles aged 9.5 ± 3.2 months and weighing 13.4 ± 2.3 kg. Study Design Randomized cross-over design. Methods Each dog was given either 4.0 mg kg−1 of ASG-oxymorphone or 8.0 mg kg−1 of ASG-hydromorphone SC on separate occasions with a 3-month washout period. Blood was collected at baseline and at serial time points up to 1032 hours (43 days) after injection for determination of serum opioid concentrations. Serum opioid concentrations were measured with HPLC-MS and pharmacokinetic parameters were calculated using commercial software and non-compartmental methods. Results Serum concentrations of oxymorphone remained above the limit of quantification for 21 days, while those for hydromorphone remained above the limit of quantification for 29 days. Cmax for ASG-oxymorphone was 7.5 ng mL−1; Cmax for ASG-hydromorphone was 5.7 ng mL−1. Conclusions and clinical relevance Oxymorphone and hydromorphone, when encapsulated into liposomes using the ammonium sulfate gradient loading technique, result in measureable serum concentrations for between 3 to 4 weeks. This formulation may have promise in the convenient use of opioids for clinical treatment of chronically painful conditions in dogs. PMID:23601353

Opioid-Induced Bowel Dysfunction

PubMed Central

Cheng, Vivian; Lembo, Anthony

2013-01-01

Opioid-induced bowel dysfunction (OIBD) is a potentially debilitating side effect of chronic opioid use. It refers to a collection of primarily gastrointestinal motility disorders induced by opioids, of which opioid-induced constipation (OIC) is the most common. Management of OIBD is difficult, and affected patients will often limit their opioid intake at the expense of experiencing more pain, to reduce the negative impact of OIBD on their quality of life. Effective pharmacologic therapy for OIC is considered an unmet need and several agents have recently been given priority review and approval for OIC. Furthermore, multiple agents currently in development show promise in treating OIC without significant impact on analgesia or precipitation of withdrawal symptoms. The approval and availability of such medications would represent a significant improvement in the management of OIC and OIBD in patients with chronic pain. PMID:23900996

Opioid Peptidomimetics: Leads for the Design of Bioavailable Mixed Efficacy Mu Opioid Receptor (MOR) Agonist/Delta Opioid Receptor (DOR) Antagonist Ligands

PubMed Central

Mosberg, Henry I.; Yeomans, Larisa; Harland, Aubrie A.; Bender, Aaron M.; Sobczyk-Kojiro, Katarzyna; Anand, Jessica P.; Clark, Mary J.; Jutkiewicz, Emily M.; Traynor, John R.

2013-01-01

We have previously described opioid peptidomimetic, 1, employing a tetrahydroquinoline scaffold and modeled on a series of cyclic tetrapeptide opioid agonists. We have recently described modifications to these peptides that confer a mu opioid receptor (MOR) agonist, delta opioid receptor (DOR) antagonist profile, which has been shown to reduce the development of tolerance to the analgesic actions of MOR agonists. Several such bifunctional ligands have been reported, but none has been demonstrated to cross the blood brain barrier. Here we describe the transfer of structural features that evoked MOR agonist/DOR antagonist behavior in the cyclic peptides to the tetrahydroquinoline scaffold and show that the resulting peptidomimetics maintain the desired pharmacological profile. Further, the 4R diastereomer of 1 was fully efficacious and approximately equipotent to morphine in the mouse warm water tail withdrawal assay following intraperitoneal administration and thus a promising lead for the development of opioid analgesics with reduced tolerance. PMID:23419026

A Novel Strategy for Attenuating Opioid Withdrawal in Neonates

PubMed Central

Santoro, Giovanni C; Shukla, Samarth; Patel, Krishna; Kaczmarzyk, Jakub; Agorastos, Stergiani; Scherrer, Sandra; Choi, Yoon Young; Veith, Christina; Carrion, Joseph; Silverman, Rebecca; Mullin, Danielle; Ahmed, Mohamed; Schiffer, Wynne K; Brodie, Jonathan D; Dewey, Stephen L

2016-01-01

The rate of Neonatal Abstinence Syndrome (NAS) has drastically increased over the past decade. The average hospital expense per NAS patient has tripled, while the number of babies born to opioid-dependent mothers has increased to 5 in 1000 births. Current treatment options are limited to opioid replacement and tapering. Consequently, we examined the efficacy of prenatal, low-dose and short-term vigabatrin (γ-vinyl GABA, GVG) exposure for attenuating these symptoms as well as the metabolic changes observed in the brains of these animals upon reaching adolescence. Pregnant Sprague-Dawley rats were treated in one of four ways: 1) saline; 2) morphine alone; 3) morphine+GVG at 25 mg/kg; 4) morphine+GVG at 50 mg/kg. Morphine was administered throughout gestation, while GVG administration occurred only during the last 5 days of gestation. On post-natal day 1, naloxone-induced withdrawal behaviours were recorded in order to obtain a gross behaviour score. Approximately 28 days following birth, 18FDG microPET scans were obtained on these same animals (Groups 1, 2, and 4). Morphine-treated neonates demonstrated significantly higher withdrawal scores than saline controls. However, GVG at 50 but not 25 mg/kg/day significantly attenuated them. Upon reaching adolescence, morphine treated animals showed regionally specific changes in 18FDG uptake. Again, prenatal GVG exposure blocked them. These data demonstrate that low-dose, short-term prenatal GVG administration blocks naloxone-induced withdrawal in neonates. Taken together, these preliminary findings suggest that GVG may provide an alternative and long-lasting pharmacologic approach for the management of neonatal and adolescent symptoms associated with NAS. PMID:28078167

Extended release naltrexone injection is performed in the majority of opioid dependent patients receiving outpatient induction: a very low dose naltrexone and buprenorphine open label trial.

PubMed

Mannelli, Paolo; Wu, Li-Tzy; Peindl, Kathleen S; Swartz, Marvin S; Woody, George E

2014-05-01

The approval of extended release injectable naltrexone (XR-NTX; Vivitrol(®)) has introduced a new option for treating opioid addiction, but studies are needed to identify its place within the spectrum of available therapies. The absence of physiological opioid dependence is a necessary and challenging first step for starting XR-NTX. Outpatient detoxification gives poor results and inpatient detoxification is either unavailable or too brief for the physiological effects of opioids to resolve. Here we present findings from an open label study that tested whether the transition from opioid addiction to XR-NTX can be safely and effectively performed in an outpatient setting using very low dose naltrexone and buprenorphine. Twenty treatment seeking opioid addicted individuals were given increasing doses of naltrexone starting at 0.25mg with decreasing doses of buprenorphine starting at 4 mg during a 7-day outpatient XR-NTX induction procedure. Withdrawal discomfort, craving, drug use, and adverse events were assessed daily until the XR-NTX injection, then weekly over the next month. Fourteen of the 20 participants received XR-NTX and 13 completed weekly assessments. Withdrawal, craving, and opioid or other drug use were significantly lower during induction and after XR-NTX administration compared with baseline, and no serious adverse events were recorded. Outpatient transition to XR-NTX combining upward titration of very low dose naltrexone with downward titration of low dose buprenorphine was safe, well tolerated, and completed by most participants. Further studies with larger numbers of subjects are needed to see if this approach is useful for naltrexone induction. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

[Interaction of opioid analgesics at the level of biotransformation].

PubMed

Petri, H; Grandt, D

2016-12-01

Opioids are an important component of the drug treatment of patients with acute and chronic pain. They differ in effectiveness, side effect profile and the risk of interactions. In this article the pharmacokinetic mechanisms of drug-drug interactions at the level of biotransformation are described and the clinical consequences which can arise are discussed. The relation of the active components to the two isoenzymes CYP2D6 and CYP3A4 is of major importance for assessing the potential drug-drug interactions of opioid analgesics at the level of the cytochrome P450 enzyme.

Therapeutic switch to buprenorphine/naloxone from buprenorphine alone: clinical experience in an Italian addiction centre.

PubMed

Montesano, Franco; Zaccone, Domenico; Battaglia, Egidio; Genco, Felice; Mellace, Vincenzo

2010-01-01

Pharmacological therapy has an important place in the management of opioid dependence. Methadone has been the mainstay of therapy but has a number of limitations. Buprenorphine monotherapy is another option, but misuse and diversion can have negative consequences. The opioid receptor antagonist, naloxone, has been added to buprenorphine to create a combination product with a reduced potential for misuse and diversion. This study evaluated the use of buprenorphine/naloxone for 24 weeks as a pharmacological management of opioid-dependent patients after therapeutic switch from buprenorphine alone. Patients (n = 43) received sublingual tablets of buprenorphine/naloxone. The buprenorphine dose was 2-24 mg (mean 16). Patients saw a physician, including an interview using a structured data sheet, and had counselling each week. Assessments were performed at week 2 (period 1), week 6 (period 2), week 16 (period 3) and week 24 (period 4). Laboratory immunoenzymatic testing was performed weekly to detect drugs in the urine. The management of withdrawal symptoms was rated as 'satisfactory' by 67% of patients during period 1 and 91% during period 4. The majority of patients was highly satisfied with therapy and considered that buprenorphine/naloxone provided good control of cravings. Two patients dropped out of therapy, but all others continued to receive buprenorphine throughout the study. Approximately 50% of patients stated that they disliked the sensory properties (taste, colour, odour and feel) of buprenorphine/naloxone. Adverse effects were as would be expected on the basis of the mechanism of action of buprenorphine (i.e. opioid-induced constipation) and for patients undergoing drug withdrawal. Only 2% of patients attempted the intravenous misuse of buprenorphine/naloxone, none of whom experienced any gratifying effects. Opioid-dependent patients maintained on buprenorphine monotherapy can be safely switched to a sublingual buprenorphine/naloxone tablet without any loss of treatment effectiveness. Buprenorphine/naloxone can be administered in an outpatient or primary care setting, and effectively controls cravings and withdrawal symptoms. Patient satisfaction was high, making retention in treatment more likely.

Rates of opioid dispensing and overdose after introduction of abuse-deterrent extended-release oxycodone and withdrawal of propoxyphene.

PubMed

Larochelle, Marc R; Zhang, Fang; Ross-Degnan, Dennis; Wharam, J Frank

2015-06-01

In the second half of 2010, abuse-deterrent extended-release oxycodone hydrochloride (OxyContin; Purdue Pharma) was introduced and propoxyphene was withdrawn from the US market. The effect of these pharmaceutical market changes on opioid dispensing and overdose rates is unknown. To evaluate the association between 2 temporally proximate changes in the opioid market and opioid dispensing and overdose rates. Claims from a large national US health insurer were analyzed, using an interrupted time series study design. Participants included an open cohort of 31.3 million commercially insured members aged 18 to 64 years between January 1, 2003, and December 31, 2012, with median follow-up of 20 months (last follow-up, December 31, 2012). Introduction of abuse-deterrent OxyContin (resistant to crushing or dissolving) on August 9, 2010, and market withdrawal of propoxyphene on November 19, 2010. Standardized opioid dispensing rates and prescription opioid and heroin overdose rates were the primary outcomes. We used segmented regression to analyze changes in outcomes from 30 quarters before to 8 quarters after the 2 interventions. Two years after the opioid market changes, total opioid dispensing decreased by 19% from the expected rate (absolute change, -32.2 mg morphine-equivalent dose per member per quarter [95% CI, -38.1 to -26.3]). By opioid subtype, the absolute change in dispensing by milligrams of morphine-equivalent dose per member per quarter at 2 years was -11.3 (95% CI, -12.4 to -10.1) for extended-release oxycodone, 3.26 (95% CI, 1.40 to 5.12) for other long-acting opioids, -8.19 (95% CI, -9.30 to -7.08) for propoxyphene, and -16.2 (95% CI, -18.8 to -13.5) for other immediate-release opioids. Two years after the market changes, the estimated overdose rate attributed to prescription opioids decreased by 20% (absolute change, -1.10 per 100,000 members per quarter [95% CI, -1.47 to -0.74]), but heroin overdose increased by 23% (absolute change, 0.26 per 100,000 members per quarter [95% CI, -0.01 to 0.53]). Opioid dispensing and prescription opioid overdoses decreased substantially after 2 major changes in the pharmaceutical market in late 2010. Pharmaceutical market interventions may have value in combatting the prescription opioid overdose epidemic, but heroin overdose rates continue to increase. Complementary strategies to identify and treat opioid abuse and addiction are urgently needed.

Safety and tolerability of the switch from buprenorphine to buprenorphine/naloxone in an Italian addiction treatment centre.

PubMed

Stimolo, Clementina; Favero, Valentina Del; Zecchinato, Giancarlo; Buson, Roberto; Cusin, Davide; Pellachin, Patrizia; Simonetto, Pamela

2010-01-01

Abuse and misuse of pharmacological therapies represent major challenges in the healthcare system, particularly in patients receiving long-acting opioid drugs for the treatment of heroin or opioid addiction. The partial mu-opioid receptor agonist buprenorphine is used to treat opioid dependence, but diversion and misuse may occur. The sublingual combination formulation of buprenorphine and the opioid receptor antagonist naloxone (buprenorphine/naxolone) is associated with a reduced abuse potential, and has been shown to have promising efficacy for the treatment of opioid dependence. This observational study assessed the safety and efficacy of sublingual buprenorphine/naloxone combination therapy in patients with opioid dependence after therapeutic switch from buprenorphine monotherapy. A total of 94 patients being treated with buprenorphine monotherapy (average dose 8 mg/day; mean duration of therapy 840 days) were switched to buprenorphine/naloxone combination therapy. Patients were asked to rate their level of satisfaction with buprenorphine/naloxone combination treatment with respect to the management of withdrawal symptoms, and urinary toxicology tests were carried out before and 14 days after switching to combination therapy. Within 3 months, 75/94 patients (80%) previously treated with buprenorphine monotherapy had switched to sublingual buprenorphine/naloxone combination treatment (average dose buprenorphine 8 mg). Among patients receiving combination treatment for >3 months, 83% were receiving medication either weekly or fortnightly, based on the results of toxicological testing. A reduction in positive urinary toxicology tests was observed in patients within two weeks after being switched to combination treatment (before switch: 28, 9 and 2 positive tests for heroin, cocaine and heroin + cocaine, respectively vs 11, 3 and 1 after switch) and a total of 64 patients of the 75 who switched to combination therapy (85%) were satisfied with the management of withdrawal symptoms during buprenorphine/naloxone treatment. Few adverse events were reported and no patients dropped out of treatment. This study shows that switching from buprenorphine monotherapy to sublingual buprenorphine/naloxone combination therapy is effective and well tolerated, and associated with good control of withdrawal symptoms in the majority of patients. In addition, combination therapy reduced illicit drug use (based on negative urinary toxicology texts) and allowed the time between clinic visits to be increased.

HIV-gp120 and physical dependence to buprenorphine.

PubMed

Palma, J; Abood, M E; Benamar, K

2015-05-01

Opioids are among the most effective and commonly used analgesics in clinical practice for severe pain. However, the use of opioid medications is clinically limited by several adverse properties including dependence. While opioid dependence is a complex health condition, the treatment of HIV-infected individuals with opioid dependence presents additional challenges. The goal of this study was to examine the physical dependence to buprenorphine in the context of HIV. Young adult male rats (Sprague-Dawley) were pretreated with HIV-1 envelope glycoprotein 120 (gp120) injected into the periaqueductal gray area (PAG) and we examined the impact on physical dependence to opioid. It was found that the physical dependence to methadone occurred earlier than that to buprenorphine, and that gp120 did not enhance or precipitate the buprenorphine withdrawal. The results suggest that buprenorphine could be the better therapeutic option to manage opioid dependence in HIV. Copyright © 2015. Published by Elsevier Ireland Ltd.

The α3β4* nicotinic ACh receptor subtype mediates physical dependence to morphine: mouse and human studies.

PubMed

Muldoon, P P; Jackson, K J; Perez, E; Harenza, J L; Molas, S; Rais, B; Anwar, H; Zaveri, N T; Maldonado, R; Maskos, U; McIntosh, J M; Dierssen, M; Miles, M F; Chen, X; De Biasi, M; Damaj, M I

2014-08-01

Recent data have indicated that α3β4* neuronal nicotinic (n) ACh receptors may play a role in morphine dependence. Here we investigated if nACh receptors modulate morphine physical withdrawal. To assess the role of α3β4* nACh receptors in morphine withdrawal, we used a genetic correlation approach using publically available datasets within the GeneNetwork web resource, genetic knockout and pharmacological tools. Male and female European-American (n = 2772) and African-American (n = 1309) subjects from the Study of Addiction: Genetics and Environment dataset were assessed for possible associations of polymorphisms in the 15q25 gene cluster and opioid dependence. BXD recombinant mouse lines demonstrated an increased expression of α3, β4 and α5 nACh receptor mRNA in the forebrain and midbrain, which significantly correlated with increased defecation in mice undergoing morphine withdrawal. Mice overexpressing the gene cluster CHRNA5/A3/B4 exhibited increased somatic signs of withdrawal. Furthermore, α5 and β4 nACh receptor knockout mice expressed decreased somatic withdrawal signs compared with their wild-type counterparts. Moreover, selective α3β4* nACh receptor antagonists, α-conotoxin AuIB and AT-1001, attenuated somatic signs of morphine withdrawal in a dose-related manner. In addition, two human datasets revealed a protective role for variants in the CHRNA3 gene, which codes for the α3 nACh receptor subunit, in opioid dependence and withdrawal. In contrast, we found that the α4β2* nACh receptor subtype is not involved in morphine somatic withdrawal signs. Overall, our findings suggest an important role for the α3β4* nACh receptor subtype in morphine physical dependence. © 2014 The British Pharmacological Society.

Fatal poisonings involving propoxyphene before and after voluntary withdrawal from the United States' market: An analysis from the state of Florida.

PubMed

Delcher, Chris; Chen, Guanming; Wang, Yanning; Slavova, Svetla; Goldberger, Bruce A

2017-11-01

The synthetic opioid propoxyphene was a schedule IV controlled substance with multiple reported health risks before the US Food and Drug Administration issued a request for voluntary market withdrawal in November 2010. The purpose of this study is to investigate the characteristics and occurrences of propoxyphene-related deaths in Florida before and after voluntary market removal. Decedent-level toxicology data from Florida's Medical Examiners Commission was used to compare the temporal, polysubstance use, sociodemographic, and geographic profiles associated with propoxyphene-involved deaths for a pre-withdrawal (November 2008-November 2010) and post-withdrawal (December 2010-December 2012) period. Sensitivity analyses using multiple data sources, including Florida's Prescription Drug Monitoring Program and other states' data, were conducted to examine potential reporting bias. Results showed that the number of propoxyphene-involved deaths declined by 84% from 580 deaths to 92 deaths after market withdrawal. The co-occurrence of other prevalent drugs, such as oxycodone (17.2% to 26.1%, p=0.0422) increased significantly in the post-withdrawal study period. A larger proportion of the propoxyphene-related deaths were reported from South Florida after the withdrawal (28.4% to 56.5%, p<0.0001). No significant changes in age and race/ethnicity were observed. Sensitivity analyses revealed that several deaths occurred in other states after market withdrawal, as recently as 2016. Our findings are consistent with previous studies that propoxyphene was still available after removal from the US market. Continued surveillance is recommended after highly abused opioids are withdrawn from the market due to on-going safety risks. Copyright © 2017 Elsevier B.V. All rights reserved.

Current and Potential Pharmacological Treatment Options for Maintenance Therapy in Opioid-Dependent Individuals

PubMed Central

Tetrault, Jeanette M.; Fiellin, David A.

2013-01-01

Opioid dependence, manifesting as addiction to heroin and pharmaceutical opioids is increasing. Internationally, there are an estimated 15.6 million illicit opioid users. The global economic burden of opioid dependence is profound both in terms of HIV and hepatitis C virus transmission, direct healthcare costs, and indirectly through criminal activity, absenteeism and lost productivity. Opioid agonist medications, such as methadone and buprenorphine, that stabilize neuronal systems and provide narcotic blockade are the most effective treatments. Prolonged provision of these medications, defined as maintenance treatment, typically produces improved outcomes when compared with short-duration tapers and withdrawal. The benefits of opioid agonist maintenance include decreased illicit drug use, improved retention in treatment, decreased HIV risk behaviours and decreased criminal behaviour. While regulations vary by country, these medications are becoming increasingly available internationally, especially in regions experiencing rapid transmission of HIV due to injection drug use. In this review, we describe the rationale for maintenance treatment of opioid dependence, discuss emerging uses of opioid antagonists such as naltrexone, and sustained-release formulations of naltrexone and buprenorphine, and provide a description of the experimental therapies. PMID:22235870

Neonatal abstinence syndrome: Historical perspective, current focus, future directions.

PubMed

Jones, Hendrée E; Fielder, Andrea

2015-11-01

Neonatal abstinence syndrome (NAS) occurs following prenatal opioid exposure. It is characterized by signs and symptoms indicating central nervous system hyperirritability and autonomic nervous system, gastrointestinal tract, and respiratory system dysfunction. This article: (1) briefly reviews NAS history, including initial identification, assessment, and treatment efforts; (2) summarizes the current status of and current issues surrounding recent NAS assessment and treatment, and (3) details future directions in NAS conceptualization, measurement, and treatment. Mortality rate estimates in neonates treated for NAS exceeded 33%, and surpassed 90% for un-treated infants during the late-1800s until the mid-1900s. The focus of both assessment and treatment over the past 50years is predominantly due to two forces. First, methadone pharmacotherapy for "heroin addiction" led to women in methadone maintenance programs who were, or became pregnant. The second was defining NAS and developing a measure of neonatal withdrawal, the Neonatal Abstinence Scoring System (NASS). Various NAS treatment protocols were based on the NASS as well as other NAS measures. Future research must focus on psychometrically sound screening and assessment measures of neonatal opioid withdrawal for premature, term and older infants, measuring and treating possible withdrawal from non-opioids, particularly benzodiazepines, integrated non-pharmacological treatment of NAS, weight-based versus symptom-based treatment of NAS, and second-line treatment for NAS. Copyright © 2015 Elsevier Inc. All rights reserved.

Past anabolic-androgenic steroid use among men admitted for substance abuse treatment: an underrecognized problem?

PubMed

Kanayama, Gen; Cohane, Geoffrey H; Weiss, Roger D; Pope, Harrison G

2003-02-01

Recent reports suggest that anabolic-androgenic steroids (AAS) may cause mood disorders or dependence syndromes and may help to introduce some individuals to opioid abuse. At present, however, little is known about prior AAS use among men entering inpatient substance abuse treatment. We assessed lifetime AAS use in 223 male substance abusers admitted to a substance abuse treatment unit primarily for treatment of alcohol, cocaine, and opioid dependence. Subjects reporting definite or possible AAS use were then asked to participate in a detailed semistructured interview that covered demographics, drug use history, and symptoms experienced during AAS use and withdrawal, and whether AAS use had helped introduce the subject to other classes of drugs. Twenty-nine men (13%) reported prior AAS use, but this history was documented on physicians' admission evaluations in only 4 cases. Among 88 men listing opioids as their drug of choice, 22 (25%) acknowledged AAS use, versus only 7 (5%) of the other 135 men (p <.001). Twenty-four (83%) of the 29 AAS users were interviewed in detail. Seven (29%) of the men interviewed, all with opioid dependence, reported that they first learned about opioids from friends at the gym and subsequently first obtained opioids from the same person who had sold them AAS. Eighteen (75%) of the men interviewed reported that AAS were the first drugs that they had ever self-administered by injection, 4 (17%) reported severe aggressiveness or violence during AAS use, 1 (4%) attempted suicide during AAS withdrawal, and 5 (21%) described a history of AAS dependence. Prior AAS use appears to be common but underrecognized among men entering inpatient substance abuse treatment, especially those with opioid dependence. AAS use may serve as a "gateway" to opioid abuse in some cases and may also cause morbidity in its own right.

Opioid analgesics: does potency matter?

PubMed

Passik, Steven D; Webster, Lynn

2014-01-01

Prescription opioid analgesics with a wide range of potencies are currently used for the treatment of chronic pain. Yet understanding the clinical relevance and therapeutic consequences of opioid potency remains ill defined. Both patients and clinicians alike have misperceptions about opioid potency, expecting that less-potent opioids will be less effective or fearing that more-potent opioids are more dangerous or more likely to be abused. In this review, common myths about the potency of opioid analgesics will be discussed. Clinicians should understand that pharmacologic potency per se does not necessarily imply more effective analgesia or higher abuse liability. Published dose conversion tables may not accurately calculate the dose for effective and safe rotation from one opioid to another in patients receiving long-term opioid therapy because they are based on limited data that may not apply to chronic pain. Differences in pharmacologic potency are largely accounted for by the actual doses prescribed, according to individualized patient need. Factors for achieving effective analgesia and reducing the risks involved with opioid use include careful medication selection based on patient characteristics, appropriate dosing titration and opioid rotation practices, knowledge of product formulation characteristics (eg, extended release, immediate release, and tamper-resistant features), and an awareness of differences in opioid pharmacokinetics and metabolism. Clinicians should remain vigilant in monitoring patients on any opioid medication, regardless of classification along the opioid potency continuum.

Opioid Addiction: Social Problems Associated and Implications of Both Current and Possible Future Treatments, including Polymeric Therapeutics for Giving Up the Habit of Opioid Consumption.

PubMed

Benéitez, M Cristina; Gil-Alegre, M Esther

2017-01-01

Detoxification programmes seek to implement the most secure and compassionate ways of withdrawing from opiates so that the inevitable withdrawal symptoms and other complications are minimized. Once detoxification has been achieved, the next stage is to enable the patient to overcome his or her drug addiction by ensuring consumption is permanently and completely abandoned, only after which can the subject be regarded as fully recovered. A systematic search on the common databases of relevant papers published until 2016 inclusive. Our study of the available oral treatments for opioid dependence has revealed that no current treatment can actually claim to be fully effective. These treatments require daily oral administration and, consequently, regular visits to dispensaries, which in most cases results in a lack of patient compliance, which causes fluctuations in drug plasma levels. We then reviewed alternative treatments in the available scientific literature on polymeric sustained release formulations. Research has been done not only on release systems for detoxification but also on release systems for giving up the habit of taking opioids. These efforts have obtained the recent authorization of polymeric systems for use in patients that could help them to reduce their craving for drugs.

Drugged Driving

MedlinePlus

... ctrl+c to copy Additional Drug Facts NIDA Science Spotlight- Cannabis Effects on Driving Performance View the ... to First FDA-Approved Medication for Opioid Withdrawal Science Highlight Scientists discover path to better pain medicines ...

The Association between Outpatient Buprenorphine Detoxification Duration and Clinical Treatment Outcomes: A Review

PubMed Central

Sigmon, Stacey C.; Strain, Eric C.; Heil, Sarah H.; Higgins, Stephen T.

2011-01-01

Background The association between buprenorphine taper duration and treatment outcomes is not well understood. This review evaluated whether duration of outpatient buprenorphine taper is significantly associated with treatment outcomes. Methods Studies that were published in peer-reviewed journals, administered buprenorphine as an outpatient taper to opioid-dependent participants, and provided data on at least one of three primary treatment outcome measures (opioid abstinence, retention, peak withdrawal severity) were reviewed. Primary treatment outcomes were evaluated as a function of taper duration using hierarchical linear regressions using pre-taper maintenance as a cofactor. Results Twenty-eight studies were reviewed. Taper duration significantly predicted percent of opioid-negative samples provided during treatment, however pre-taper maintenance period predicted percent participants abstinent on the final day of treatment. High rates of relapse were reported. No significant association between taper duration and retention in treatment or peak withdrawal severity was observed. Conclusion The data reviewed here suggest taper duration is associated with opioid abstinence achieved during detoxification but not with other markers of treatment outcome. The reviewed studies varied widely on several parameters (e.g., frequency of urinalysis testing, provision of ancillary medications) that may influence treatment outcome and thus could have interfered with the ability to identify relationships between taper duration and outcomes. Future studies evaluating opioid detoxification should utilize rigorous experimental methods and report a wider range of outcome measures in order to help advance our understanding of the association between taper duration and treatment outcomes. PMID:21741781

TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION AT BOTH HIGH AND LOW FREQUENCIES ACTIVATES VENTROLATERAL PERIAQUEDUCTAL GREY TO DECREASE MECHANICAL HYPERALGESIA IN ARTHRITIC RATS

PubMed Central

Desantana, J. M.; Da Silva, L. F. S.; De Resende, M. A.; Sluka, K. A.

2014-01-01

Transcutaneous electric nerve stimulation (TENS) is widely used for the treatment of pain. TENS produces an opioid-mediated antinociception that utilizes the rostroventromedial medulla (RVM). Similarly, antinociception evoked from the periaqueductal grey (PAG) is opioid-mediated and includes a relay in the RVM. Therefore, we investigated whether the ventrolateral or dorsolateral PAG mediates antinociception produced by TENS in rats. Paw and knee joint mechanical withdrawal thresholds were assessed before and after knee joint inflammation (3% kaolin/carrageenan), and after TENS stimulation (active or sham). Cobalt chloride (CoCl2; 5 mM) or vehicle was microinjected into the ventrolateral periaqueductal grey (vlPAG) or dorsolateral periaqueductal grey (dlPAG) prior to treatment with TENS. Either high (100 Hz) or low (4 Hz) frequency TENS was then applied to the inflamed knee for 20 min. Active TENS significantly increased withdrawal thresholds of the paw and knee joint in the group microinjected with vehicle when compared to thresholds prior to TENS (P<0.001) or to sham TENS (P<0.001). The increases in withdrawal thresholds normally observed after TENS were prevented by microinjection of CoCl2 into the vlPAG, but not the dlPAG prior to TENS and were significantly lower than controls treated with TENS (P<0.001). In a separate group of animals, microinjection of CoCl2 into the vlPAG temporarily reversed the decreased mechanical withdrawal threshold suggesting a role for the vlPAG in the facilitation of joint pain. No significant difference was observed for dlPAG. We hypothesize that the effects of TENS are mediated through the vlPAG that sends projections through the RVM to the spinal cord to produce an opioid-mediated analgesia. PMID:19576962

Naloxegol: A Novel Therapy in the Management of Opioid-Induced Constipation.

PubMed

Jones, Rachel; Prommer, Eric; Backstedt, David

2016-11-01

Opioid-related bowel dysfunction is a common and potentially severe adverse effect from treatment with opioid analgesics. Its development is not dose related, nor do patients develop tolerance. Opioid-induced constipation (OIC) can lead to fecal impaction, bowel obstruction, and bowel perforation as well as noncompliance with opioid analgesics and poor quality of life. Routine administration of laxatives is necessary to maintain bowel function, and, in refractory cases, other modalities must be pursued. Available options are limited but include peripherally acting μ-opioid receptor antagonists (PAMORAs), including methylnaltrexone. Naloxegol is a newly developed PAMORA that is available through the oral route. At the therapeutic dose of 25 mg daily, naloxegol is effective and safe, with a limited side effect profile and is associated with preservation of centrally mediated analgesia. In this article, we discuss the pharmacokinetics, pharmacodynamics, adverse effects, clinical trials, and cost considerations of naloxegol. Finally, we discuss its potential role as a novel key treatment for OIC in palliative medicine patients. © The Author(s) 2015.

Comorbid Post-Traumatic Stress Disorder and Opioid Dependence.

PubMed

Patel, Rikinkumar S; Elmaadawi, Ahmed; Nasr, Suhayl; Haskin, John

2017-09-03

Post-traumatic stress disorder (PTSD) is predominant amongst individuals addicted to opioids and obscures the course of illness and the treatment outcome. We report the case of a patient with major depressive disorder and opioid dependence, who experienced post-traumatic stress disorder symptoms during a recent visit to the inpatient unit. The similarity of symptoms between post-traumatic stress disorder and opioid dependence is so high that, sometimes, it is a challenge to differentiate between these conditions. Since opioid withdrawal symptoms mimic hyper vigilance, this results in an exaggeration of the response of patients with post-traumatic stress disorder. This comorbidity is associated with worse health outcomes, as its pathophysiology involves a common neurobiological circuit. Opioid substitution therapy and psychotherapeutic medications in combination with evidence-based cognitive behavioral therapy devised for individuals with comorbid post-traumatic stress disorder and opioid dependence may improve treatment outcomes in this population. Therefore, we conclude that the screening for post-traumatic stress disorder in the opioid-abusing population is crucial. To understand the underlying mechanisms for this comorbidity and to improve the treatment response, further research should be encouraged.

Evaluation of CART peptide level in rat plasma and CSF: Possible role as a biomarker in opioid addiction.

PubMed

Bakhtazad, Atefeh; Vousooghi, Nasim; Garmabi, Behzad; Zarrindast, Mohammad Reza

2016-10-01

It has been shown previously that cocaine- and amphetamine-regulated transcript (CART) peptide has a modulatory role and homeostatic regulatory effect in motivation to and reward of the drugs of abuse specially psychostimulants. Recent data also showed that in addition to psychostimulants, CART is critically involved in the different stages of opioid addiction. Here we have evaluated the fluctuations in the level of CART peptide in plasma and CSF in different phases of opioid addiction to find out whether CART can serve as a suitable marker in opioid addiction studies. Male rats were randomly distributed in groups of control, acute low-dose (10mg/kg) morphine, acute high-dose morphine (80mg/kg), chronic escalating doses of morphine, withdrawal syndrome precipitated by administration of naloxone (1mg/kg), and abstinent after long-term drug-free maintenance of addicted animals. The level of CART peptide in CSF and plasma samples was measured by enzyme immunoassay. CART peptide concentration in the CSF and plasma was significantly elevated in acute high-dose morphine and withdrawal state animals and down-regulated in addicted rats. In abstinent group, CART peptide level was up-regulated in plasma but not in CSF samples. As the observed results are in agreement with data regarding the CART mRNA and protein expression in the brain reward pathway in opioid addiction phases, it may be suggested that evaluation of CART peptide level in CSF or plasma could be a suitable marker which reflects the rises and falls of the peptide concentration in brain in the development of opioid addiction. Copyright © 2016 Elsevier Inc. All rights reserved.

Pharmacokinetics of butorphanol after intravenous, intramuscular, and oral administration in Hispaniolan Amazon parrots (Amazona ventralis).

PubMed

Guzman, David Sanchez-Migallon; Flammer, Keven; Paul-Murphy, Joanne R; Barker, Steven A; Tully, Thomas N

2011-09-01

Previous studies have validated the clinical use of opioids with kaap-receptor affinities for pain management in birds. Butorphanol, a kappa opioid receptor agonist and a mu opioid receptor antagonist, is currently considered by many clinicians to be the opioid of choice for this use. However, despite studies reporting the analgesic properties of butorphanol in psittacine birds, dosing intervals have not been established for any psittacine species. The goals of this study in the Hispaniolan Amazon parrot (Amazona ventralis) were to evaluate the pharmacokinetics of butorphanol tartrate after intravenous (IV), intramuscular (IM), and oral (PO) administration and to determine the bioavailability of butorphanol tartrate after oral administration. Twelve Hispaniolan Amazon parrots were used in the study, with a complete-crossover experimental design and a 3-month period separating each part of the study. The birds were randomly assigned to 3 groups (n = 4) for each stage. Butorphanol tartrate was administered once at a dose of 5 mg/kg in the basilic vein or pectoral muscles or as an oral solution delivered via feeding tube into the crop for the IV, IM, and PO studies, respectively. After butorphanol administration, blood samples were collected at 1, 5, 15, 30, 60, 90, 120, 180, and 240 minutes for the IV and IM studies and at 5, 15, 30, 60, 90, 120, 180, 240, and 300 minutes for the PO study. Because of the size limitation of the birds, naive pooling of datum points was used to generate a mean plasma butorphanol concentration at each time point. For each study, birds in each group (n = 4) were bled 3 times after dosing. Plasma butorphanol concentrations were determined by high-performance liquid chromatography/tandem mass spectrometry, and pharmacokinetic parameters were calculated. Butorphanol tartrate was found to have high bioavailability and rapid elimination following IM administration. In contrast, oral administration resulted in low bioavailability (< 10%), thus precluding the use of this route of administration for clinical purposes. Based on these results, in Hispaniolan Amazon parrots, butorphanol tartrate dosed at 5 mg/kg IV or IM would have to be administered every 2 and 3 hours, respectively, to maintain plasma concentrations consistent with published therapeutic levels. To our knowledge, this is the first published study presenting the pharmacokinetic analysis of butorphanol tartrate in a psittacine species as well as the first study presenting pharmacokinetic analysis of butorphanol after oral administration in any avian species.

Addiction as a Stress Surfeit Disorder

PubMed Central

Koob, George F.; Buck, Cara L.; Cohen, Ami; Edwards, Scott; Park, Paula E.; Schlosburg, Joel E.; Schmeichel, Brooke; Vendruscolo, Leandro F.; Wade, Carrie L.; Whitfield, Timothy W.; George, Olivier

2013-01-01

Drug addiction has been conceptualized as a chronically relapsing disorder of compulsive drug seeking and taking that progresses through three stages: binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation. Drug addiction impacts multiple motivational mechanisms and can be conceptualized as a disorder that progresses from positive reinforcement (binge/intoxication stage) to negative reinforcement (withdrawal/negative affect stage). The construct of negative reinforcement is defined as drug taking that alleviates a negative emotional state. Our hypothesis is that the negative emotional state that drives such negative reinforcement is derived from dysregulation of key neurochemical elements involved in the brain stress systems within the frontal cortex, ventral striatum, and extended amygdala. Specific neurochemical elements in these structures include not only recruitment of the classic stress axis mediated by corticotropin-releasing factor (CRF) in the extended amygdala as previously hypothesized but also recruitment of dynorphin-κ opioid aversive systems in the ventral striatum and extended amygdala. Additionally, we hypothesized that these brain stress systems may be engaged in the frontal cortex early in the addiction process. Excessive drug taking engages activation of CRF not only in the extended amygdala, accompanied by anxiety-like states, but also in the medial prefrontal cortex, accompanied by deficits in executive function that may facilitate the transition to compulsive-like responding. Excessive activation of the nucleus accumbens via the release of mesocorticolimbic dopamine or activation of opioid receptors has long been hypothesized to subsequently activate the dynorphin-κ opioid system, which in turn can decrease dopaminergic activity in the mesocorticolimbic dopamine system. Blockade of the κ opioid system can also block anxiety-like and reward deficits associated with withdrawal from drugs of abuse and block the development of compulsive-like responding during extended access to drugs of abuse, suggesting another powerful brain stress/anti-reward system that contributes to compulsive drug seeking. Thus, brain stress response systems are hypothesized to be activated by acute excessive drug intake, to be sensitized during repeated withdrawal, to persist into protracted abstinence, and to contribute to the development and persistence of addiction. The recruitment of anti-reward systems provides a powerful neurochemical basis for the negative emotional states that are responsible for the dark side of addiction. PMID:23747571

Tolerance and sensitization to chronic escalating-dose heroin following extended withdrawal in Fischer rats: possible role of mu-opioid receptors

PubMed Central

Seip-Cammack, Katharine M.; Reed, Brian; Zhang, Yong; Ho, Ann; Kreek, Mary Jeanne

2012-01-01

Rationale/objectives Heroin addiction is characterized by recurrent cycles of drug use, abstinence and relapse. It is likely that neurobiological changes during chronic heroin exposure persist across withdrawal and impact behavioral responses to re-exposure. We hypothesized that, after extended withdrawal, heroin-withdrawn rats would express behavioral tolerance and/or sensitization in response to heroin re-exposure and that these responses might be associated with altered mu-opioid receptor (MOPr) activity. Methods Male Fischer rats were exposed chronically to escalating doses of heroin (7.5–75mg/kg/day), experienced acute spontaneous withdrawal and extended (10-day) abstinence, and were re-exposed chronically to heroin. Homecage behaviors and locomotor activity in response to heroin, as well as somatic withdrawal signs, were recorded. Separate groups of rats were sacrificed after extended abstinence and MOPr expression and G-protein coupling were analyzed using [3H]DAMGO and [35S]GTPγS assays. Results The depth of behavioral stupor was lower during the initial days of heroin re-exposure compared to the initial days of the first exposure period. Behavioral responses (e.g., stereotypy) and locomotion were elevated in response to heroin re-exposure at low doses. Rats conditioned for heroin place preference during the chronic re-exposure period expressed heroin preference during acute withdrawal; this preference was stronger than rats conditioned during chronic heroin exposure that followed chronic saline and injection-free periods. Extended withdrawal was associated with increased MOPr expression in the caudate-putamen and frontal and cingulate cortices. No changes in G-protein coupling were identified. Conclusions Aspects of tolerance/sensitization to heroin are present even after extended abstinence and may be associated with altered MOPr density. PMID:22829433

Corticotropin-releasing factor (CRF) and α 2 adrenergic receptors mediate heroin withdrawal-potentiated startle in rats.

PubMed

Park, Paula E; Vendruscolo, Leandro F; Schlosburg, Joel E; Edwards, Scott; Schulteis, Gery; Koob, George F

2013-09-01

Anxiety is one of the early symptoms of opioid withdrawal and contributes to continued drug use and relapse. The acoustic startle response (ASR) is a component of anxiety that has been shown to increase during opioid withdrawal in both humans and animals. We investigated the role of corticotropin-releasing factor (CRF) and norepinephrine (NE), two key mediators of the brain stress system, on acute heroin withdrawal-potentiated ASR. Rats injected with heroin (2 mg/kg s.c.) displayed an increased ASR when tested 4 h after heroin treatment. A similar increase in ASR was found in rats 10-20 h into withdrawal from extended access (12 h) to i.v. heroin self-administration, a model that captures several aspects of heroin addiction in humans. Both the α 2 adrenergic receptor agonist clonidine (10 μg/kg s.c.) and CRF1 receptor antagonist N,N-bis(2-methoxyethyl)-3-(4-methoxy-2-methylphenyl)-2,5-dimethyl-pyrazolo[1,5-a] pyrimidin-7-amine (MPZP; 20 mg/kg s.c.) blocked heroin withdrawal-potentiated startle. To investigate the relationship between CRF1 and α 2 adrenergic receptors in the potentiation of the ASR, we tested the effect of MPZP on yohimbine (1.25 mg/kg s.c.)-potentiated startle and clonidine on CRF (2 μg i.c.v.)-potentiated startle. Clonidine blocked CRF-potentiated startle, whereas MPZP partially attenuated but did not reverse yohimbine-potentiated startle, suggesting that CRF may drive NE release to potentiate startle. These results suggest that CRF1 and α 2 receptors play an important role in the heightened anxiety-like behaviour observed during acute withdrawal from heroin, possibly via CRF inducing the release of NE in stress-related brain regions.

Hyperhidrosis (Excessive Sweating)

MedlinePlus

... your daily routine Sweating causes emotional distress or social withdrawal You suddenly begin to sweat more than usual ... can lead to heavy sweating, as can opioid ... infections. Social and emotional effects. Having clammy or dripping hands ...

“Listening” and “talking” to neurons: Implications of immune activation for pain control and increasing the efficacy of opioids

PubMed Central

Watkins, Linda R.; Hutchinson, Mark R.; Milligan, Erin D.; Maier, Steven F.

2008-01-01

It is recently become clear that activated immune cells and immune-like glial cells can dramatically alter neuronal function. By increasing neuronal excitability, these non-neuronal cells are now implicated in the creation and maintenance of pathological pain, such as occurs in response to peripheral nerve injury. Such effects are exerted at multiple sites along the pain pathway, including at peripheral nerves, dorsal root ganglia, and spinal cord. In addition, activated glial cells are now recognized as disrupting the pain suppressive effects of opioid drugs and contributing to opioid tolerance and opioid dependence/withdrawal. While this review focuses on regulation of pain and opioid actions, such immune-neuronal interactions are broad in their implications. Such changes in neuronal function would be expected to occur wherever immune-derived substances come in close contact with neurons. PMID:17706291

[Continuous subcutaneous infusion of opioids in cancer patients].

PubMed

Galamba, J M; Olsen, A K; Crawford, M E; Sjøgren, P

1995-07-17

This review article describes pharmacokinetics, pharmaco-dynamics, side effects and the practical use of continuous subcutaneous infusion of opioids in cancer patients with pain. Clinical studies have shown that the analgesic effects of continuous subcutaneous infusion of morphine are comparable to continuous intravenous morphine, and that the treatment modality is associated with a low frequency of side-effects and complications. Continuous subcutaneous infusions of morphine are therefore recommended as the treatment of choice for cancer patients with pain, when oral analgesic treatment is no longer possible.

Opioid glycopeptide analgesics derived from endogenous enkephalins and endorphins

PubMed Central

Li, Yingxue; Lefever, Mark R; Muthu, Dhanasekaran; Bidlack, Jean M; Bilsky, Edward J; Polt, Robin

2012-01-01

Over the past two decades, potent and selective analgesics have been developed from endogenous opioid peptides. Glycosylation provides an important means of modulating interaction with biological membranes, which greatly affects the pharmacodynamics and pharmacokinetics of the resulting glycopeptide analogues. Furthermore, manipulation of the membrane affinity allows penetration of cellular barriers that block efficient drug distribution, including the blood–brain barrier. Extremely potent and selective opiate agonists have been developed from endogenous peptides, some of which show great promise as drug candidates. PMID:22300099

The prescription opioid epidemic: a review of qualitative studies on the progression from initial use to abuse

PubMed Central

Cicero, Theodore J.; Ellis, Matthew S.

2017-01-01

Most research designed to answer the “why” of the prescription opioid epidemic has relied on structured interviews, which rigidly attempt to capture the complex reasons people use opioids. In contrast this systematic literature review focuses on peer-reviewed studies that have used a qualitative approach to examine the development of an opioid-use disorder from the point of initial exposure. Rather than simply providing a “high,” opioids reportedly relieve psychological/emotional problems or provide an escape from life stressors. As use continues, avoidance of withdrawal sickness becomes an overriding concern, with all other benefits playing minor roles in persistent use. These studies indicate that terms used in structured interviews, such as “nontherapeutic use” or variations thereof, poorly capture the complex range of needs opioids satisfy. Both quantitative/structured studies and more qualitative ones, as well as more focused studies, have an important role in better informing prevention and treatment efforts. PMID:29302223

Hypothesizing that a Pro-Dopaminergic Regulator (KB220z™ Liquid Variant) can Induce “Dopamine Homeostasis” and Provide Adjunctive Detoxification Benefits in Opiate/Opioid Dependence

PubMed Central

Blum, Kenneth; Whitney, Debra; Fried, Lye; Febo, Marcelo; Waite, Roger L; Braverman, Eric R; Dushaj, Kristina; Li, Mona; Giordano, John; Demetrovics, Zsolt; Badgaiyan, Rajendra D

2017-01-01

In order to explore the initiation of detoxification of addictive patients to opiates/opioids (along with some other anti-withdrawal agents), we developed a protocol to be utilized in treatment centers particularly with heavily dependent opiate/opioid subjects. Out of 17 subjects, only three received Buprenorphine/Naloxone (Bup/nx) along with KB220Z. In this pilot, we first used a dose of KB220Z of 2 oz twice daily before meals along with clonidine and benzodiazepines and other anti-nausea and sleep aids including Gabapentin. The dose of KB220Z was maintained for 6 days in five individuals. In a second scenario, we utilized a higher dose of 4 oz every 6 hours, over a 6-day period. The higher dose was employed in another 12 patients. It is noteworthy that only 3 people have relapsed utilizing these two protocols during the first two weeks of the study, allowing for the remaining 82% to be maintained on KB220Z. The patients have been maintained without any additional Bup/nx for a minimum of 120 days and in one subject, 214 days. We are in the process of testing this hypothesis in multiple treatment centers across the United Sates utilizing data from the Clinical opiate Withdrawal Scale (COWS) pre and post KB220Z. We are in the process of testing this hypothesis in multiple treatment centers across the United Sates. While this does not constitute an acceptable controlled experiment, it does provide some preliminary evidence that agrees with an earlier study. Moreover, because of the utilization of standard detoxifying agents in this detoxification protocol, we cannot make any inference to KB220Z’s effects. However, out of 17 subjects, only three required Bup/nx suggesting an interesting finding. If further confirmed in larger studies, the utilization for opiate/opioid detoxification may provide a novel way to eliminate the need for addictive opioids during withdrawal and detoxification. This paradigm shift may translate to a reduction in utilizing powerful and addictive opioids like buprenorphine and methadone (especially in these patients at high genetic risk for addiction) as not only detoxifying agents, but also maintenance drugs. While extensive research is required, this pilot paves the way for future investigations that could assist in the reduction of addictive opiate/opioid use and mortalities amongst both the young and old in America. PMID:29034323

"Should I stay or should I go?" Coming off methadone and buprenorphine treatment.

PubMed

Winstock, Adam R; Lintzeris, Nicholas; Lea, Toby

2011-01-01

This study aimed to investigate patient perspectives regarding coming off maintenance opioid substitution treatment (OST). The study explored previous experiences, current interest and concerns about stopping treatment, and perceptions of how and when coming off treatment should be supported. A cross-sectional survey was used. Participants were 145 patients receiving OST at public opioid treatment clinics in Sydney, Australia. Sixty-two percent reported high interest in coming off treatment in the next 6 months. High interest was associated with having discussed coming off treatment with a greater number of categories of people (OR=1.72), not citing concern about heroin relapse (OR=3.18), and shorter duration of current treatment episode (OR=0.99). Seventy-one percent reported previous withdrawal attempts and 23% had achieved opioid abstinence for ≥3 months following a previous withdrawal attempt. Attempts most commonly involved jumping off (59%), and doctor-controlled (52%) or self-controlled (48%) gradual reduction. For future attempts respondents were most interested in doctor-controlled (68%) or self-controlled (41%) gradual reduction. Concerns regarding coming off treatment included withdrawal discomfort (68%), increased pain (50%), and relapse to heroin use (48%). While some patients may require lifetime maintenance, the issue of coming off treatment is important to many patients and should be discussed regularly throughout treatment and where appropriate supported by a menu of clinical options. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.

Resolution of an oral ulcer secondary to acetaminophen/hydrocodone withdrawal.

PubMed

Balasubramaniam, Ramesh; Lin, Po-Ching; White, Dean K; Yepes, Juan F

2007-01-01

Acetaminophen/hydrocodone is a common non-opioid/opioid analgesic indicated for the treatment of moderate to severe pain. The following report depicts a unique case involving a 57-year-old woman with a persistent, painful oral ulcer that was unresponsive to standard treatments. The ulcer was resolved when the patient discontinued acetaminophen/hydrocodone use. The cause of the ulcer is unclear but it was speculated to result from a systemic hypersensitivity reaction to acetaminophen/hydrocodone.

Pharmacodynamic and pharmacokinetic studies of agmatine after spinal administration in the mouse.

PubMed

Roberts, John C; Grocholski, Brent M; Kitto, Kelley F; Fairbanks, Carolyn A

2005-09-01

Agmatine is an endogenous decarboxylation product of arginine that has been previously shown to antagonize the N-methyl-d-aspartate (NMDA) receptor and inhibit nitric-oxide synthase. Many neuropharmacological studies have shown that exogenous administration of agmatine prevents or reverses biological phenomena dependent on central nervous system glutamatergic systems, including opioid-induced tolerance, opioid self-administration, and chronic pain. However, the central nervous system (CNS) pharmacokinetic profile of agmatine remains minimally defined. The present study determined the spinal cord pharmacokinetics and acute pharmacodynamics of intrathecally administered agmatine in mice. After a single bolus intrathecal injection, agmatine concentrations in spinal cord (cervical, thoracic, and lumbosacral) tissue and serum were quantified by an isocratic high-performance liquid chromatography fluorescence detection system. Agmatine persisted at near maximum concentrations in all levels of the spinal cord for several hours with a half-life of approximately 12 h. Initial agmatine concentrations in serum were 10% those in CNS. However, the serum half-life was less than 10 min after intrathecal injection of agmatine, consistent with previous preliminary pharmacokinetic reports of systemically administered agmatine. The pharmacodynamic response to agmatine in the NMDA-nociceptive behavior and thermal hyperalgesia tests was assessed. Whereas MK-801 (dizocilpine maleate) inhibits these two responses with equal potency, agmatine inhibits the thermal hyperalgesia with significantly increased potency compared with the nociceptive behavior, suggesting two sites of action. In contrast to the pharmacokinetic results, the agmatine inhibition of both behaviors had a duration of only 10 to 30 min. Collectively, these results suggest the existence of a currently undefined agmatinergic extracellular clearance process in spinal cord.

Kratom, an Emerging Drug of Abuse: A Case Report of Overdose and Management of Withdrawal.

PubMed

Diep, Jack; Chin, David Tian; Gupta, Somdatta; Syed, Faraz; Xiong, Ming; Cheng, Jianguo

2018-04-15

Kratom is an herb indigenous to Southeast Asia with psychoactive opioid compounds, often used as a treatment for chronic pain or opiate withdrawal symptoms. It is legally and readily available via Internet sales and has been identified as an emerging drug of abuse in the United States. Kratom use has been associated with psychosis, seizures, and even death. At lower doses, kratom acts as a stimulant, while at higher doses, it produces analgesia and euphoria. Here, we describe the successful management of kratom overdose and withdrawal in a young man with negative toxicology screens.

Kratom, an Emerging Drug of Abuse: A Case Report of Overdose and Management of Withdrawal.

PubMed

Diep, Jack; Chin, David Tian; Gupta, Somdatta; Syed, Faraz; Xiong, Ming; Cheng, Jianguo

2017-10-26

Kratom is an herb indigenous to Southeast Asia with psychoactive opioid compounds, often used as a treatment for chronic pain or opiate withdrawal symptoms. It is legally and readily available via Internet sales and has been identified as an emerging drug of abuse in the United States. Kratom use has been associated with psychosis, seizures, and even death. At lower doses, kratom acts as a stimulant, while at higher doses, it produces analgesia and euphoria. Here, we describe the successful management of kratom overdose and withdrawal in a young man with negative toxicology screens.

Buprenorphine implants for treatment of opioid dependence: a randomized controlled trial.

PubMed

Ling, Walter; Casadonte, Paul; Bigelow, George; Kampman, Kyle M; Patkar, Ashwin; Bailey, Genie L; Rosenthal, Richard N; Beebe, Katherine L

2010-10-13

Limitations of existing pharmacological treatments for opioid dependence include low adherence, medication diversion, and emergence of withdrawal symptoms. To determine the efficacy of buprenorphine implants that provide a low, steady level of buprenorphine over 6 months for the treatment of opioid dependence. A randomized, placebo-controlled, 6-month trial conducted at 18 sites in the United States between April 2007 and June 2008. One hundred sixty-three adults, aged 18 to 65 years, diagnosed with opioid dependence. One hundred eight were randomized to receive buprenorphine implants and 55 to receive placebo implants. After induction with sublingual buprenorphine-naloxone tablets, patients received either 4 buprenorphine implants (80 mg per implant) or 4 placebo implants. A fifth implant was available if a threshold for rescue use of sublingual buprenorphine-naloxone treatment was exceeded. Standardized individual drug counseling was provided to all patients. The percentage of urine samples negative for illicit opioids for weeks 1 through 16 and for weeks 17 through 24. The buprenorphine implant group had significantly more urine samples negative for illicit opioids during weeks 1 through 16 (P = .04). Patients with buprenorphine implants had a mean percentage of urine samples that tested negative for illicit opioids across weeks 1 through 16 of 40.4% (95% confidence interval [CI], 34.2%-46.7%) and a median of 40.7%; whereas those in the placebo group had a mean of 28.3% (95% CI, 20.3%-36.3%) and a median of 20.8%. A total of 71 of 108 patients (65.7%) who received buprenorphine implants completed the study vs 17 of 55 (30.9%) who received placebo implants (P < .001). Those who received buprenorphine implants also had fewer clinician-rated (P <.001) and patient-rated (P = .004) withdrawal symptoms, had lower patient ratings of craving (P <.001), and experienced a greater change on clinician global ratings of severity of opioid dependence (P<.001) and on the clinician global ratings of improvement (P < .001) than those who received placebo implants. Minor implant site reactions were the most common adverse events: 61 patients (56.5%) in the buprenorphine group and 29 (52.7%) in the placebo group. Among persons with opioid dependence, the use of buprenorphine implants compared with placebo resulted in less opioid use over 16 weeks as assessed by urine samples. clinicaltrials.gov Identifier: NCT00447564.

42 CFR 8.34 - Court review of final administrative action; exhaustion of administrative remedies.

Code of Federal Regulations, 2010 CFR

2010-10-01

... HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID TREATMENT PROGRAMS Procedures for... Withdrawal of Approval of an Accreditation Body § 8.34 Court review of final administrative action...

42 CFR 8.34 - Court review of final administrative action; exhaustion of administrative remedies.

Code of Federal Regulations, 2011 CFR

2011-10-01

... HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID TREATMENT PROGRAMS Procedures for... Withdrawal of Approval of an Accreditation Body § 8.34 Court review of final administrative action...

The α3β4* nicotinic ACh receptor subtype mediates physical dependence to morphine: mouse and human studies

PubMed Central

Muldoon, P P; Jackson, K J; Perez, E; Harenza, J L; Molas, S; Rais, B; Anwar, H; Zaveri, N T; Maldonado, R; Maskos, U; McIntosh, J M; Dierssen, M; Miles, M F; Chen, X; De Biasi, M; Damaj, M I

2014-01-01

BACKGROUND AND PURPOSE Recent data have indicated that α3β4* neuronal nicotinic (n) ACh receptors may play a role in morphine dependence. Here we investigated if nACh receptors modulate morphine physical withdrawal. EXPERIMENTAL APPROACHES To assess the role of α3β4* nACh receptors in morphine withdrawal, we used a genetic correlation approach using publically available datasets within the GeneNetwork web resource, genetic knockout and pharmacological tools. Male and female European-American (n = 2772) and African-American (n = 1309) subjects from the Study of Addiction: Genetics and Environment dataset were assessed for possible associations of polymorphisms in the 15q25 gene cluster and opioid dependence. KEY RESULTS BXD recombinant mouse lines demonstrated an increased expression of α3, β4 and α5 nACh receptor mRNA in the forebrain and midbrain, which significantly correlated with increased defecation in mice undergoing morphine withdrawal. Mice overexpressing the gene cluster CHRNA5/A3/B4 exhibited increased somatic signs of withdrawal. Furthermore, α5 and β4 nACh receptor knockout mice expressed decreased somatic withdrawal signs compared with their wild-type counterparts. Moreover, selective α3β4* nACh receptor antagonists, α-conotoxin AuIB and AT-1001, attenuated somatic signs of morphine withdrawal in a dose-related manner. In addition, two human datasets revealed a protective role for variants in the CHRNA3 gene, which codes for the α3 nACh receptor subunit, in opioid dependence and withdrawal. In contrast, we found that the α4β2* nACh receptor subtype is not involved in morphine somatic withdrawal signs. CONCLUSION AND IMPLICATIONS Overall, our findings suggest an important role for the α3β4* nACh receptor subtype in morphine physical dependence. PMID:24750073

Safety and pharmacokinetics of oral cannabidiol when administered concomitantly with intravenous fentanyl in humans

PubMed Central

Manini, Alex F.; Yiannoulos, Georgia; Bergamaschi, Mateus M.; Hernandez, Stephanie; Olmedo, Ruben; Barnes, Allan J.; Winkel, Gary; Sinha, Rajita; Jutras-Aswad, Didier; Huestis, Marilyn A.; Hurd, Yasmin L.

2015-01-01

Objectives Cannabidiol (CBD) is hypothesized as a potential treatment for opioid addiction, with safety studies an important first step for medication development. We determined CBD safety and pharmacokinetics when administered concomitantly with a high-potency opioid in healthy subjects. Methods This double-blind, placebo-controlled cross-over study of CBD co-administered with intravenous fentanyl, was conducted at the Clinical Research Center in Mount Sinai Hospital, a tertiary care medical center in New York City. Participants were healthy volunteers aged 21–65 years with prior opioid exposure, regardless of route. Blood samples were obtained before and after 400 or 800 mg CBD pretreatment, followed by a single 0.5 (Session 1) or 1.0mcg/Kg (Session 2) intravenous fentanyl dose. The primary outcome was the Systematic Assessment for Treatment Emergent Events (SAFTEE) to assess safety and adverse effects. CBD peak plasma concentrations, time to reach peak plasma concentrations (tmax), and area under the curve (AUC) were measured. Results SAFTEE data were similar between groups without respiratory depression or cardiovascular complications during any test session. Following low dose CBD, tmax occurred at 3 and 1.5h (Sessions 1 and 2, respectively). Following high dose CBD, tmax occurred at 3 and 4h in Sessions 1 and 2, respectively. There were no significant differences in plasma CBD or cortisol (AUC p=NS) between sessions. Conclusions CBD does not exacerbate adverse effects associated with intravenous fentanyl administration. Co-administration of CBD and opioids was safe and well tolerated. These data provide the foundation for future studies examining CBD as a potential treatment for opioid abuse. PMID:25748562

Evidence that opioids may have toll-like receptor 4 and MD-2 effects.

PubMed

Hutchinson, Mark R; Zhang, Yingning; Shridhar, Mitesh; Evans, John H; Buchanan, Madison M; Zhao, Tina X; Slivka, Peter F; Coats, Benjamen D; Rezvani, Niloofar; Wieseler, Julie; Hughes, Travis S; Landgraf, Kyle E; Chan, Stefanie; Fong, Stephanie; Phipps, Simon; Falke, Joseph J; Leinwand, Leslie A; Maier, Steven F; Yin, Hang; Rice, Kenner C; Watkins, Linda R

2010-01-01

Opioid-induced proinflammatory glial activation modulates wide-ranging aspects of opioid pharmacology including: opposition of acute and chronic opioid analgesia, opioid analgesic tolerance, opioid-induced hyperalgesia, development of opioid dependence, opioid reward, and opioid respiratory depression. However, the mechanism(s) contributing to opioid-induced proinflammatory actions remains unresolved. The potential involvement of toll-like receptor 4 (TLR4) was examined using in vitro, in vivo, and in silico techniques. Morphine non-stereoselectively induced TLR4 signaling in vitro, blocked by a classical TLR4 antagonist and non-stereoselectively by naloxone. Pharmacological blockade of TLR4 signaling in vivo potentiated acute intrathecal morphine analgesia, attenuated development of analgesic tolerance, hyperalgesia, and opioid withdrawal behaviors. TLR4 opposition to opioid actions was supported by morphine treatment of TLR4 knockout mice, which revealed a significant threefold leftward shift in the analgesia dose response function, versus wildtype mice. A range of structurally diverse clinically-employed opioid analgesics was found to be capable of activating TLR4 signaling in vitro. Selectivity in the response was identified since morphine-3-glucuronide, a morphine metabolite with no opioid receptor activity, displayed significant TLR4 activity, whilst the opioid receptor active metabolite, morphine-6-glucuronide, was devoid of such properties. In silico docking simulations revealed ligands bound preferentially to the LPS binding pocket of MD-2 rather than TLR4. An in silico to in vitro prediction model was built and tested with substantial accuracy. These data provide evidence that select opioids may non-stereoselectively influence TLR4 signaling and have behavioral consequences resulting, in part, via TLR4 signaling.

Evidence that opioids may have toll like receptor 4 and MD-2 effects

PubMed Central

Hutchinson, Mark R.; Zhang, Yingning; Shridhar, Mitesh; Evans, John H.; Buchanan, Madison M.; Zhao, Tina X.; Slivka, Peter F.; Coats, Benjamen D.; Rezvani, Niloofar; Wieseler, Julie; Hughes, Travis S.; Landgraf, Kyle E.; Chan, Stefanie; Fong, Stephanie; Phipps, Simon; Falke, Joseph J.; Leinwand, Leslie A.; Maier, Steven F.; Yin, Hang; Rice, Kenner C.; Watkins, Linda R.

2009-01-01

Opioid-induced proinflammatory glial activation modulates wide-ranging aspects of opioid pharmacology including: opposition of acute and chronic opioid analgesia, opioid analgesic tolerance, opioid-induced hyperalgesia, development of opioid dependence, opioid reward, and opioid respiratory depression. However, the mechanism(s) contributing to opioid-induced proinflammatory actions remains unresolved. The potential involvement of toll like receptor 4 (TLR4) was examined using in vitro, in vivo, and in silico techniques. Morphine non-stereoselectively induced TLR4 signaling in vitro, blocked by a classical TLR4 antagonist and non-stereoselectively by naloxone. Pharmacological blockade of TLR4 signaling in vivo potentiated acute intrathecal morphine analgesia, attenuated development of analgesic tolerance, hyperalgesia, and opioid withdrawal behaviors. TLR4 opposition to opioid actions was supported by morphine treatment of TLR4 knockout mice, which revealed a significant threefold leftward shift in the analgesia dose response function, versus wildtype mice. A range of structurally diverse clinically employed opioid analgesics was found to be capable of activating TLR4 signaling in vitro. Selectivity in the response was identified since morphine-3-glucuronide, a morphine metabolite with no opioid receptor activity, displayed significant TLR4 activity, whilst the opioid receptor active metabolite, morphine-6-glucuronide, was devoid of such properties. In silico docking simulations revealed ligands bound preferentially to the LPS binding pocket of MD-2 rather than TLR4. An in silico to in vitro prediction model was built and tested with substantial accuracy. These data provide evidence that select opioids may non-stereoselectively influence TLR4 signaling and have behavioral consequences resulting, in part, via TLR4 signaling. PMID:19679181

Reasons for Benzodiazepine Use Among Persons Seeking Opioid Detoxification.

PubMed

Stein, Michael D; Kanabar, Mitika; Anderson, Bradley J; Lembke, Anna; Bailey, Genie L

2016-09-01

Over the past decade, patients admitted to addiction treatment programs have reported increasing rates of concurrent opioid and benzodiazepine (BZD) use. This drug combination places individuals at high risk for accidental overdose. Little is known about reasons for BZD use among individuals seeking treatment for opioid use disorders. We surveyed consecutive persons initiating inpatient opioid detoxification and identified 176 out of 438 who reported BZD use in the past 30 days and/or had a positive toxicology. Forty percent of persons surveyed used a BZD in the month prior to admission, and 25% of these met criteria for BZD dependence (DSM IV). BZD users averaged 32.0 years of age, 63.6% were male, 85.2% used heroin, and reported, on average, 13.3 (±11.2) days of BZD use during the past month. Alprazolam (Xanax) was the most commonly used BZD (52%), and buying it on the street the most common source (48%). The most commonly reported reason for BZD use was 'to manage anxiety' (42.6%), followed by 'to get or enhance a high' (27.7%), 'to help with sleep' (11.4%), and 'to decrease opioid withdrawal' (10.2%). The most common reason for BZD use was significantly associated (p<.001) with most likely source of BZDs, with persons who got their BZDs from a prescriber (23%) more likely to report BZD anxiety as their primary reason for use, while persons who bought BZDs on "the street" (48%) had the highest likelihood of reporting using BZD to get or enhance a high. Participants using BZDs most commonly for anxiety did not endorse lower anxiety than those using BZDs for other reasons. Two in five persons seeking detoxification for an opioid use disorder used a BZD in the prior month. Anxiety was the most common reason patients reported using a benzodiazepine, but they also reported using BZDs to enhance a 'high' and manage opioid withdrawal. Evidence-based discussions about the risks of combining BZDs and opioids, and alternatives to BZDs should be a high priority in detoxification settings. Copyright © 2016 Elsevier Inc. All rights reserved.

Musical Agency during Physical Exercise Decreases Pain.

PubMed

Fritz, Thomas H; Bowling, Daniel L; Contier, Oliver; Grant, Joshua; Schneider, Lydia; Lederer, Annette; Höer, Felicia; Busch, Eric; Villringer, Arno

2017-01-01

Objectives: When physical exercise is systematically coupled to music production, exercisers experience improvements in mood, reductions in perceived effort, and enhanced muscular efficiency. The physiology underlying these positive effects remains unknown. Here we approached the investigation of how such musical agency may stimulate the release of endogenous opioids indirectly with a pain threshold paradigm. Design: In a cross-over design we tested the opioid-hypothesis with an indirect measure, comparing the pain tolerance of 22 participants following exercise with or without musical agency. Method: Physical exercise was coupled to music by integrating weight-training machines with sensors that control music-synthesis in real time. Pain tolerance was measured as withdrawal time in a cold pressor test. Results: On average, participants tolerated cold pain for ~5 s longer following exercise sessions with musical agency. Musical agency explained 25% of the variance in cold pressor test withdrawal times after factoring out individual differences in general pain sensitivity. Conclusions: This result demonstrates a substantial pain reducing effect of musical agency in combination with physical exercise, probably due to stimulation of endogenous opioid mechanisms. This has implications for exercise endurance, both in sports and a multitude of rehabilitative therapies in which physical exercise is effective but painful.

Musical Agency during Physical Exercise Decreases Pain

PubMed Central

Fritz, Thomas H.; Bowling, Daniel L.; Contier, Oliver; Grant, Joshua; Schneider, Lydia; Lederer, Annette; Höer, Felicia; Busch, Eric; Villringer, Arno

2018-01-01

Objectives: When physical exercise is systematically coupled to music production, exercisers experience improvements in mood, reductions in perceived effort, and enhanced muscular efficiency. The physiology underlying these positive effects remains unknown. Here we approached the investigation of how such musical agency may stimulate the release of endogenous opioids indirectly with a pain threshold paradigm. Design: In a cross-over design we tested the opioid-hypothesis with an indirect measure, comparing the pain tolerance of 22 participants following exercise with or without musical agency. Method: Physical exercise was coupled to music by integrating weight-training machines with sensors that control music-synthesis in real time. Pain tolerance was measured as withdrawal time in a cold pressor test. Results: On average, participants tolerated cold pain for ~5 s longer following exercise sessions with musical agency. Musical agency explained 25% of the variance in cold pressor test withdrawal times after factoring out individual differences in general pain sensitivity. Conclusions: This result demonstrates a substantial pain reducing effect of musical agency in combination with physical exercise, probably due to stimulation of endogenous opioid mechanisms. This has implications for exercise endurance, both in sports and a multitude of rehabilitative therapies in which physical exercise is effective but painful. PMID:29387030

Discovery and development of tramadol for the treatment of pain.

PubMed

Bravo, Lidia; Mico, Juan Antonio; Berrocoso, Esther

2017-12-01

Tramadol is an opioid drug that, unlike classic opioids, also modulates the monoaminergic system by inhibiting noradrenergic and serotoninergic reuptake. For this reason, tramadol is considered an atypical opioid. These special pharmacological characteristics have made tramadol one of the most commonly prescribed analgesic drugs to treat moderate to severe pain. Areas covered: The aim of this review is to provide a historical description of the biochemistry, pharmacokinetics and particularly, the mechanisms of action of tramadol. In addition, a summary is offered of the analgesic effects of tramadol in a variety of animal models of acute and chronic pain. Finally, clinical studies that demonstrate the efficacy and safety of tramadol in the treatment of pain are also assessed. Expert opinion: The discovery that tramadol combines opioid and monoaminergic effects represented a milestone in the evolution of pain treatment. Given its 'mild effect' on opioid receptors, tramadol induces fewer side effects than classic opioids. Tramadol produces satisfactory analgesia against various types of pain and it is currently approved for the treatment of moderate to severe pain. Thus, the combination of monoamine and opioid mechanisms opens new avenues for the design of innovative analgesics.

Pain Therapy Guided by Purpose and Perspective in Light of the Opioid Epidemic

PubMed Central

Severino, Amie L.; Shadfar, Arash; Hakimian, Joshua K.; Crane, Oliver; Singh, Ganeev; Heinzerling, Keith; Walwyn, Wendy M.

2018-01-01

Prescription opioid misuse is an ongoing and escalating epidemic. Although these pharmacological agents are highly effective analgesics prescribed for different types of pain, opioids also induce euphoria, leading to increasing diversion and misuse. Opioid use and related mortalities have developed in spite of initial claims that OxyContin, one of the first opioids prescribed in the USA, was not addictive in the presence of pain. These claims allayed the fears of clinicians and contributed to an increase in the number of prescriptions, quantity of drugs manufactured, and the unforeseen diversion of these drugs for non-medical uses. Understanding the history of opioid drug development, the widespread marketing campaign for opioids, the immense financial incentive behind the treatment of pain, and vulnerable socioeconomic and physical demographics for opioid misuse give perspective on the current epidemic as an American-born problem that has expanded to global significance. In light of the current worldwide opioid epidemic, it is imperative that novel opioids are developed to treat pain without inducing the euphoria that fosters physical dependence and addiction. We describe insights from preclinical findings on the properties of opioid drugs that offer insights into improving abuse-deterrent formulations. One finding is that the ability of some agonists to activate one pathway over another, or agonist bias, can predict whether several novel opioid compounds bear promise in treating pain without causing reward among other off-target effects. In addition, we outline how the pharmacokinetic profile of each opioid contributes to their potential for misuse and discuss the emergence of mixed agonists as a promising pipeline of opioid-based analgesics. These insights from preclinical findings can be used to more effectively identify opioids that treat pain without causing physical dependence and subsequent opioid abuse. PMID:29740351

Effect of chronic delivery of the Toll-like receptor 4 antagonist (+)-Naltrexone on incubation of heroin craving

PubMed Central

Theberge, Florence R.; Li, Xuan; Kambhampati, Sarita; Pickens, Charles L.; St. Laurent, Robyn; Bossert, Jennifer M.; Baumann, Michael H.; Hutchinson, Mark R.; Rice, Kenner C.; Watkins, Linda R.; Shaham, Yavin

2013-01-01

Background Recent evidence implicates toll-like receptor 4 (TLR4) in opioid analgesia, tolerance, conditioned place preference, and self-administration. Here we determined the effect of the TLR4 antagonist (+)-naltrexone (a μ-opioid receptor inactive isomer) on the time-dependent increases in cue-induced heroin seeking after withdrawal (incubation of heroin craving). Methods In an initial experiment, we trained rats for 9 h/day to self-administer heroin (0.1 mg/kg/infusion) for 9 days; lever presses were paired with a 5-sec tone-light cue. We then assessed cue-induced heroin seeking in 30-min extinction sessions on withdrawal day 1; immediately after testing, we surgically implanted rats with Alzet minipumps delivering (+)-naltrexone (0, 7.5, 15, 30 mg/kg/day, s.c.) for 14 days. We then tested the rats for incubated cue-induced heroin seeking in 3-h extinction tests on withdrawal day 13. Results We found that chronic delivery of (+)-naltrexone via minipumps during the withdrawal phase decreased incubated cue-induced heroin seeking. In follow-up experiments, we found that acute injections of (+)-naltrexone immediately before withdrawal day 13 extinction test had no effect on incubated cue-induced heroin seeking. Furthermore, chronic delivery of (+)-naltrexone (15 or 30 mg/kg/day) or acute systemic injections (15 or 30 mg/kg) had no effect on ongoing extended access heroin self-administration. Finally, in rats trained to self-administer methamphetamine (0.1 mg/kg/infusion, 9 h/d, 9 days), chronic delivery of (+)-naltrexone (30 mg/kg/day) during the withdrawal phase had no effect on incubated cue-induced methamphetamine seeking. Conclusions The present results suggest a critical role of TLR4 in the development of incubation of heroin, but not methamphetamine, craving. PMID:23384483

Involvement of delta opioid receptors in alcohol withdrawal-induced mechanical allodynia in male C57BL/6 mice.

PubMed

Alongkronrusmee, Doungkamol; Chiang, Terrance; van Rijn, Richard M

2016-10-01

As a legal drug, alcohol is commonly abused and it is estimated that 17 million adults in the United States suffer from alcohol use disorder. Heavy alcoholics can experience withdrawal symptoms including anxiety and mechanical allodynia that can facilitate relapse. The molecular mechanisms underlying this phenomenon are not well understood, which stifles development of new therapeutics. Here we investigate whether delta opioid receptors (DORs) play an active role in alcohol withdrawal-induced mechanical allodynia (AWiMA) and if DOR agonists may provide analgesic relief from AWiMA. To study AWiMA, adult male wild-type and DOR knockout C57BL/6 mice were exposed to alcohol by a voluntary drinking model or oral gavage exposure model, which we developed and validated here. We also used the DOR-selective agonist TAN-67 and antagonist naltrindole to examine the involvement of DORs in AWiMA, which was measured using a von Frey model of mechanical allodynia. We created a robust model of alcohol withdrawal-induced anxiety and mechanical allodynia by orally gavaging mice with 3g/kg alcohol for three weeks. AWiMA was exacerbated and prolonged in DOR knockout mice as well as by pharmacological blockade of DORs compared to control mice. However, analgesia induced by TAN-67 was attenuated during withdrawal in alcohol-gavaged mice. DORs appear to play a protective role in the establishment of AWiMA. Our current results indicate that DORs could be targeted to prevent or reduce the development of AWiMA during alcohol use; however, DORs may be a less suitable target to treat AWiMA during active withdrawal. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

42 CFR 8.30 - Transmission of written communications by reviewing official and calculation of deadlines.

Code of Federal Regulations, 2010 CFR

2010-10-01

... HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID TREATMENT PROGRAMS Procedures for... Withdrawal of Approval of an Accreditation Body § 8.30 Transmission of written communications by reviewing...

42 CFR 8.30 - Transmission of written communications by reviewing official and calculation of deadlines.

Code of Federal Regulations, 2011 CFR

2011-10-01

... HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID TREATMENT PROGRAMS Procedures for... Withdrawal of Approval of an Accreditation Body § 8.30 Transmission of written communications by reviewing...

Suboxone misuse along the opiate maintenance treatment pathway.

PubMed

Furst, R Terry

2013-01-01

This study explores strategies that Suboxone misusers utilize while in drug treatment. Ethnographic interviews were conducted with 14 patients who had cycled in and out of Suboxone treatment. The objective of the study is to identify strategies implemented by patients who intermittently use opiates/opioids while in Suboxone treatment. Findings indicate that some patients serially stop and start treatment in a Harm Reduction setting in New York City. Many patients suggest that they manage their opiate/opioid dependency through a sequential use of Suboxone and heroin to avoid withdrawal and to continue their misuse of opiates/opioids. Results are discussed in conjunction with the difficulties inherent to substance abuse treatment and suggestions for improvement are offered.

Cocaine Dysregulates Opioid Gating of GABA Neurotransmission in the Ventral Pallidum

PubMed Central

Scofield, Michael D.; Rice, Kenner C.; Cheng, Kejun; Roques, Bernard P.

2014-01-01

The ventral pallidum (VP) is a target of dense nucleus accumbens projections. Many of these projections coexpress GABA and the neuropeptide enkephalin, a δ and μ opioid receptor (MOR) ligand. Of these two, the MOR in the VP is known to be involved in reward-related behaviors, such as hedonic responses to palatable food, alcohol intake, and reinstatement of cocaine seeking. Stimulating MORs in the VP decreases extracellular GABA, indicating that the effects of MORs in the VP on cocaine seeking are via modulating GABA neurotransmission. Here, we use whole-cell patch-clamp on a rat model of withdrawal from cocaine self-administration to test the hypothesis that MORs presynaptically regulate GABA transmission in the VP and that cocaine withdrawal changes the interaction between MORs and GABA. We found that in cocaine-extinguished rats pharmacological activation of MORs no longer presynaptically inhibited GABA release, whereas blocking the MORs disinhibited GABA release. Moreover, MOR-dependent long-term depression of GABA neurotransmission in the VP was lost in cocaine-extinguished rats. Last, GABA neurotransmission was found to be tonically suppressed in cocaine-extinguished rats. These substantial synaptic changes indicated that cocaine was increasing tone on MOR receptors. Accordingly, increasing endogenous tone by blocking the enzymatic degradation of enkephalin inhibited GABA neurotransmission in yoked saline rats but not in cocaine-extinguished rats. In conclusion, our results indicate that following withdrawal from cocaine self-administration enkephalin levels in the VP are elevated and the opioid modulation of GABA neurotransmission is impaired. This may contribute to the difficulties withdrawn addicts experience when trying to resist relapse. PMID:24431463

Morphine clearance in children: does race or genetics matter?

PubMed

Sadhasivam, Senthilkumar; Krekels, Elke H J; Chidambaran, Vidya; Esslinger, Hope R; Ngamprasertwong, Pornswan; Zhang, Kejian; Fukuda, Tsuyoshi; Vinks, Alexander A

2012-01-01

Interindividual variability in analgesic response and adverse effects of opioids because of narrow therapeutic indices are major clinical problems. Morphine is an opioid commonly used in children to manage perioperative pain. Al-though size and age often are considered primary covariates for morphine pharmacokinetic models, the impact of other factors important in personalizing care such as race and genetic variations on morphine disposition is not well documented. Genotype blinded clinical observational pharmacokinetic study. One hundred forty-six African American and Caucasian children scheduled for elective outpatient adenotonsillectomy were enrolled in our prospective genotype blinded observational study with standard perioperative clinical care. Tertiary care pediatric institution. Morphine bolus for intraoperative analgesia in children and pharmacokinetic analyses in different races. Pharmacokinetics and pharmacogenetics of intravenous morphine in a homogeneous pediatric outpatient surgical pain population were evaluated. The authors observed that African American children have higher morphine clearance than Caucasian children. The increased clearance is directed toward the formation of morphine-3-glucuronide formation, rather than the formation of morphine-6-glucuronide. Common uridine diphosphate glucuronosyl transferase (UGT) 2B7 genetic variations (2161C>T and 802C>T) were not associated with observed racial differences in morphine's clearance although the wild type of the UGT2B7 isozyme is more prevalent in the African Americans. Race of the child is an important factor in perioperative intravenous morphine's clearance and its potential role in personalizing analgesia with morphine needs further investigation.

Caring for Pregnant Women with Opioid Use Disorder in the USA: Expanding and Improving Treatment.

PubMed

Saia, Kelley A; Schiff, Davida; Wachman, Elisha M; Mehta, Pooja; Vilkins, Annmarie; Sia, Michelle; Price, Jordana; Samura, Tirah; DeAngelis, Justin; Jackson, Clark V; Emmer, Sawyer F; Shaw, Daniel; Bagley, Sarah

Opioid use disorder in the USA is rising at an alarming rate, particularly among women of childbearing age. Pregnant women with opioid use disorder face numerous barriers to care, including limited access to treatment, stigma, and fear of legal consequences. This review of opioid use disorder in pregnancy is designed to assist health care providers caring for pregnant and postpartum women with the goal of expanding evidence-based treatment practices for this vulnerable population. We review current literature on opioid use disorder among US women, existing legislation surrounding substance use in pregnancy, and available treatment options for pregnant women with opioid use disorder. Opioid agonist treatment (OAT) remains the standard of care for treating opioid use disorder in pregnancy. Medically assisted opioid withdrawal ("detoxification") is not recommended in pregnancy and is associated with high maternal relapse rates. Extended release naltrexone may confer benefit for carefully selected patients. Histories of trauma and mental health disorders are prevalent in this population; and best practice recommendations incorporate gender-specific, trauma-informed, mental health services. Breastfeeding with OAT is safe and beneficial for the mother-infant dyad. Further research investigating options of OAT and the efficacy of opioid antagonists in pregnancy is needed. The US health care system can adapt to provide quality care for these mother-infant dyads by expanding comprehensive treatment services and improving access to care.

A Report of Nausea and Vomiting with Discontinuation of Chronic Use of Salvia divinorum

PubMed Central

Travis, C. R.; Ray, G. A.; Marlowe, K. F.

2012-01-01

Introduction. This is the first reported case of gastrointestinal symptoms associated with withdrawal after chronic use of this substance. Case Presentation. A 51-year-old Caucasian woman was referred to a hospital with a 3-day history of nausea, vomiting, diarrhea, and abdominal discomfort. She reported no sick family members or contact with anyone who was ill. She did report smoking 3–5 cigarettes of the herb “Salvia” consistently for 3-4 months and quit approximately 48 hours before symptoms appeared. Her use of the herb had been consistent; she smoked several cigarettes each day. Laboratory results were essentially normal including the white blood cell count. She received symptomatic treatment and was released after one day. Discussion. Salvinorin A, a kappa-opioid receptor agonist, is the major active ingredient of S. divinorum. The unique opioid properties of this herb may explain its ability to cause changes in intestinal transit time. Conclusion. A 51-year-old woman possibly developed gastrointestinal manifestations suggestive of withdrawal from Salvia divinorum after smoking the substance consistently for 3 to 4 months. The widespread use of this herb will make the potential for withdrawal syndromes more commonplace. PMID:22611407

A Report of Nausea and Vomiting with Discontinuation of Chronic Use of Salvia divinorum.

PubMed

Travis, C R; Ray, G A; Marlowe, K F

2012-01-01

Introduction. This is the first reported case of gastrointestinal symptoms associated with withdrawal after chronic use of this substance. Case Presentation. A 51-year-old Caucasian woman was referred to a hospital with a 3-day history of nausea, vomiting, diarrhea, and abdominal discomfort. She reported no sick family members or contact with anyone who was ill. She did report smoking 3-5 cigarettes of the herb "Salvia" consistently for 3-4 months and quit approximately 48 hours before symptoms appeared. Her use of the herb had been consistent; she smoked several cigarettes each day. Laboratory results were essentially normal including the white blood cell count. She received symptomatic treatment and was released after one day. Discussion. Salvinorin A, a kappa-opioid receptor agonist, is the major active ingredient of S. divinorum. The unique opioid properties of this herb may explain its ability to cause changes in intestinal transit time. Conclusion. A 51-year-old woman possibly developed gastrointestinal manifestations suggestive of withdrawal from Salvia divinorum after smoking the substance consistently for 3 to 4 months. The widespread use of this herb will make the potential for withdrawal syndromes more commonplace.

Failure to identify or effectively manage prescription opioid dependence acted as a gateway to heroin use-buprenorphine/naloxone treatment and recovery in a surgical patient.

PubMed

Conroy, Stephen; Hill, Duncan

2014-12-17

The prescribing of opioid pain medication has increased markedly in recent years, with strong opioid dispensing increasing 18-fold in Tayside, Scotland since 1995. Despite this, little data is available to quantify the problem of opioid pain medication dependence (OPD) and until recently there was little guidance on best-practice treatment. We report the case of a young mother prescribed dihydrocodeine for postoperative pain relief who became opioid dependent. When her prescription was stopped without support, she briefly used heroin to overcome her withdrawal. After re-exposure to dihydrocodeine following surgery 9 years later and treatment with methadone for dependency, she was transferred to buprenorphine/naloxone. In our clinical experience and in agreement with Department of Health and Royal College of General Practitioner guidance, buprenorphine/naloxone is the preferred opioid substitution treatment for OPD. Our patient remains within her treatment programme and has returned to work on buprenorphine 16 mg/naloxone 4 mg in conjunction with social and psychological support. 2014 BMJ Publishing Group Ltd.

Social Stress Engages Opioid Regulation of Locus Coeruleus Norepinephrine Neurons and Induces a State of Cellular and Physical Opiate Dependence

PubMed Central

Chaijale, Nayla N; Curtis, Andre L; Wood, Susan K; Zhang, Xiao-Yan; Bhatnagar, Seema; Reyes, Beverly AS; Van Bockstaele, Elisabeth J; Valentino, Rita J

2013-01-01

Stress is implicated in diverse psychiatric disorders including substance abuse. The locus coeruleus–norepinephrine (LC–NE) system is a major stress response system that is also a point of intersection between stress neuromediators and endogenous opioids and so may be a site at which stress can influence drug-taking behaviors. As social stress is a common stressor for humans, this study characterized the enduring impact of repeated social stress on LC neuronal activity. Rats were exposed to five daily consecutive sessions of social stress using the resident-intruder model or control manipulation. LC discharge rate recorded 2 days after the last manipulation was decreased in stressed rats compared with controls. By 10 days after the last manipulation, LC rates were comparable between groups. Systemic administration of the opiate antagonist, naloxone, robustly increased LC discharge rate in a manner suggestive of opiate withdrawal, selectively in stressed rats when administered 2 or 10 days after the last manipulation. This was accompanied by behavioral signs of mild opiate withdrawal. Western blot and electron microscopic studies indicated that repeated social stress decreased corticotropin-releasing factor type 1 receptor and increased μ-opioid receptor levels in the LC. Together, the results suggest that repeated social stress engages endogenous opioid modulation of LC activity and induces signs of cellular and physical opiate dependence that endure after the stress. These cellular effects may predispose individuals with a history of repeated social stress to substance abuse behaviors. PMID:23660707

Social stress engages opioid regulation of locus coeruleus norepinephrine neurons and induces a state of cellular and physical opiate dependence.

PubMed

Chaijale, Nayla N; Curtis, Andre L; Wood, Susan K; Zhang, Xiao-Yan; Bhatnagar, Seema; Reyes, Beverly As; Van Bockstaele, Elisabeth J; Valentino, Rita J

2013-09-01

Stress is implicated in diverse psychiatric disorders including substance abuse. The locus coeruleus-norepinephrine (LC-NE) system is a major stress response system that is also a point of intersection between stress neuromediators and endogenous opioids and so may be a site at which stress can influence drug-taking behaviors. As social stress is a common stressor for humans, this study characterized the enduring impact of repeated social stress on LC neuronal activity. Rats were exposed to five daily consecutive sessions of social stress using the resident-intruder model or control manipulation. LC discharge rate recorded 2 days after the last manipulation was decreased in stressed rats compared with controls. By 10 days after the last manipulation, LC rates were comparable between groups. Systemic administration of the opiate antagonist, naloxone, robustly increased LC discharge rate in a manner suggestive of opiate withdrawal, selectively in stressed rats when administered 2 or 10 days after the last manipulation. This was accompanied by behavioral signs of mild opiate withdrawal. Western blot and electron microscopic studies indicated that repeated social stress decreased corticotropin-releasing factor type 1 receptor and increased μ-opioid receptor levels in the LC. Together, the results suggest that repeated social stress engages endogenous opioid modulation of LC activity and induces signs of cellular and physical opiate dependence that endure after the stress. These cellular effects may predispose individuals with a history of repeated social stress to substance abuse behaviors.

Acute pain management in opioid-tolerant patients: a growing challenge.

PubMed

Huxtable, C A; Roberts, L J; Somogyi, A A; MacIntyre, P E

2011-09-01

In Australia and New Zealand, in parallel with other developed countries, the number of patients prescribed opioids on a long-term basis has grown rapidly over the last decade. The burden of chronic pain is more widely recognised and there has been an increase in the use of opioids for both cancer and non-cancer indications. While the prevalence of illicit opioid use has remained relatively stable, the diversion and abuse of prescription opioids has escalated, as has the number of individuals receiving methadone or buprenorphine pharmacotherapy for opioid addiction. As a result, the proportion of opioid-tolerant patients requiring acute pain management has increased, often presenting clinicians with greater challenges than those faced when treating the opioid-naïve. Treatment aims include effective relief of acute pain, prevention of drug withdrawal, assistance with any related social, psychiatric and behavioural issues, and ensuring continuity of long-term care. Pharmacological approaches incorporate the continuation of usual medications (or equivalent), short-term use of sometimes much higher than average doses of additional opioid, and prescription of non-opioid and adjuvant drugs, aiming to improve pain relief and attenuate opioid tolerance and/or opioid-induced hyperalgesia. Discharge planning should commence at an early stage and may involve the use of a 'Reverse Pain Ladder' aiming to limit duration of additional opioid use. Legislative requirements may restrict which drugs can be prescribed at the time of hospital discharge. At all stages, there should be appropriate and regular consultation and liaison with the patient, other treating teams and specialist services.

Simulation and Prediction of the Drug-Drug Interaction Potential of Naloxegol by Physiologically Based Pharmacokinetic Modeling.

PubMed

Zhou, D; Bui, K; Sostek, M; Al-Huniti, N

2016-05-01

Naloxegol, a peripherally acting μ-opioid receptor antagonist for the treatment of opioid-induced constipation, is a substrate for cytochrome P450 (CYP) 3A4/3A5 and the P-glycoprotein (P-gp) transporter. By integrating in silico, preclinical, and clinical pharmacokinetic (PK) findings, minimal and full physiologically based pharmacokinetic (PBPK) models were developed to predict the drug-drug interaction (DDI) potential for naloxegol. The models reasonably predicted the observed changes in naloxegol exposure with ketoconazole (increase of 13.1-fold predicted vs. 12.9-fold observed), diltiazem (increase of 2.8-fold predicted vs. 3.4-fold observed), rifampin (reduction of 76% predicted vs. 89% observed), and quinidine (increase of 1.2-fold predicted vs. 1.4-fold observed). The moderate CYP3A4 inducer efavirenz was predicted to reduce naloxegol exposure by ∼50%, whereas weak CYP3A inhibitors were predicted to minimally affect exposure. In summary, the PBPK models reasonably estimated interactions with various CYP3A modulators and can be used to guide dosing in clinical practice when naloxegol is coadministered with such agents. © 2016 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

Investigation of clinical pharmacokinetic variability of an opioid antagonist through physiologically based absorption modeling.

PubMed

Ding, Xuan; He, Minxia; Kulkarni, Rajesh; Patel, Nita; Zhang, Xiaoyu

2013-08-01

Identifying the source of inter- and/or intrasubject variability in pharmacokinetics (PK) provides fundamental information in understanding the pharmacokinetics-pharmacodynamics relationship of a drug and project its efficacy and safety in clinical populations. This identification process can be challenging given that a large number of potential causes could lead to PK variability. Here we present an integrated approach of physiologically based absorption modeling to investigate the root cause of unexpectedly high PK variability of a Phase I clinical trial drug. LY2196044 exhibited high intersubject variability in the absorption phase of plasma concentration-time profiles in humans. This could not be explained by in vitro measurements of drug properties and excellent bioavailability with low variability observed in preclinical species. GastroPlus™ modeling suggested that the compound's optimal solubility and permeability characteristics would enable rapid and complete absorption in preclinical species and in humans. However, simulations of human plasma concentration-time profiles indicated that despite sufficient solubility and rapid dissolution of LY2196044 in humans, permeability and/or transit in the gastrointestinal (GI) tract may have been negatively affected. It was concluded that clinical PK variability was potentially due to the drug's antagonism on opioid receptors that affected its transit and absorption in the GI tract. Copyright © 2013 Wiley Periodicals, Inc.

Acute Myocardial Infarction following Naltrexone Consumption; a Case Report.

PubMed

Dadpour, Bita; Gholoobi, Arash; Tajoddini, Shahrad; Habibi, Amir

2017-01-01

Cardiovascular effects of opioid withdrawal have long been studied. It was reported that patients with underlying ischemic heart disease and atherosclerotic vessels may be complicated by a sudden physical and emotional stress due to withdrawal syndrome. But some other believes sudden increase in catecholamine level as a sympathetic overflow might effect on heart with and without underlying ischemia. In the current study, a patient on methadone maintenance therapy (MMT) who experienced myocardial infarction (MI) after taking naltrexone was described.

Pharmacokinetics of Oral and Intravenous Paracetamol (Acetaminophen) When Co-Administered with Intravenous Morphine in Healthy Adult Subjects.

PubMed

Raffa, Robert B; Pawasauskas, Jayne; Pergolizzi, Joseph V; Lu, Luke; Chen, Yin; Wu, Sutan; Jarrett, Brant; Fain, Randi; Hill, Lawrence; Devarakonda, Krishna

2018-03-01

Several features favor paracetamol (acetaminophen) administration by the intravenous rather than the oral route in the postoperative setting. This study compared the pharmacokinetics and bioavailability of oral and intravenous paracetamol when given with or without an opioid, morphine. In this randomized, single-blind, parallel, repeat-dose study in healthy adults, subjects received four repeat doses of oral or intravenous 1000 mg paracetamol at 6-h intervals, and morphine infusions (0.125 mg/kg) at the 2nd and 3rd intervals. Comparisons of plasma pharmacokinetic profiles were conducted before, during, and after opioid co-administrations. Twenty-two subjects were included in the pharmacokinetic analysis. Observed paracetamol peak concentration (C max ) and area under the plasma concentration-time curve over the dosing interval (AUC 0-6 ) were reduced when oral paracetamol was co-administered with morphine (reduced from 11.6 to 7.25 µg/mL and from 31.00 to 25.51 µg·h/mL, respectively), followed by an abruptly increased C max and AUC 0-6 upon discontinuation of morphine (to 13.5 µg/mL and 52.38 µg·h/mL, respectively). There was also a significantly prolonged mean time to peak plasma concentration (T max ) after the 4th dose of oral paracetamol (2.84 h) compared to the 1st dose (1.48 h). However, pharmacokinetic parameters of paracetamol were not impacted when intravenous paracetamol was co-administered with morphine. Morphine co-administration significantly impacted the pharmacokinetics of oral but not intravenous paracetamol. The abrupt release of accumulated paracetamol at the end of morphine-mediated gastrointestinal inhibition following oral but not intravenous administration of paracetamol suggests that intravenous paracetamol provides a better option for the management of postoperative pain. CLINICALTRIALS. NCT02848729.

Application of hot-melt extrusion technology in immediate-release abuse-deterrent formulations.

PubMed

Wening, Klaus; Schwier, Sebastian; Stahlberg, Hans-J; Galia, Eric

Hot-melt extrusion (HME) technology has been used for manufacturing extended-release abuse-deterrent formulations (ADFs) of opioid-type analgesics with improved tamper-resistant properties. Our objective was to describe application of this technology to immediate-release (IR) ADFs. For development of a sample IR ADF (hydrocodone 10 mg/acetaminophen 325 mg) based on HME, feasibility studies were performed using different excipients. The formulation selected for further development was evaluated via in vitro test battery. Moreover, in vivo performance of IR ADF technologies was investigated in an open-label, randomized, cross-over, phase 1, relative oral bioavailability study with another opioid (model compound). Single-center bioavailability trial. Twenty-four healthy white male subjects. ADF IR formulation of an opioid and marketed IR formulation. For feasibility and in vitro studies, dissolution profiles, syringeability, particle size distribution after physical manipulation, and extractability were evaluated. For the phase 1 study, pharmacokinetic parameters were evaluated and compared for ADF IR and a marketed IR formulation. After manipulation, the majority of particles from the ADF IR formulation were >500µm and, thus, not considered suitable for intranasal abuse, while the majority of particles for the reference marketed IR formulation were <500µm. The ADF IR formulation was resistant to syringing and preparation for potential intravenous injection. In healthy subjects, pharmacokinetics of an ADF and marketed IR formulation of an opioid were nearly identical. Application of HME to IR formulations led to development of products with improved mechanical resistance to manipulation for intranasal or intravenous preparation, but similar bioavailability.

Behavioral and electrographic effects of opioids on kindled seizures in rats.

PubMed

Caldecott-Hazard, S; Shavit, Y; Ackermann, R F; Engel, J; Frederickson, R C; Liebeskind, J C

1982-11-18

Our laboratory previously suggested that opioid peptides are released by an amygdaloid kindled seizure and may affect the elicitation of a subsequent seizure. The present study examined the effects of morphine, naloxone, enkephalin analogues, and conditions of morphine tolerance and withdrawal on the severity and duration of a series of amygdaloid kindled seizures. The results suggest two distinct opiate/opioid actions on seizures. The first is an anticonvulsant effect on the behavioral manifestations of seizures. This effect is seen following a high dose (50 mg/kg) of morphine or a low dose (6 mg/kg) of enkephalin analogue (LY146104), and is reversed by naloxone. The second is a naloxone-reversible prolonging effect of the high dose of morphine on the electrographic components of the seizures. Receptor affinities of these various opiate/opioid drugs suggest that these two actions are mediated by different receptors which appear not to include high affinity mu receptors.

Pharmacokinetics, efficacy prediction indexes, and residue depletion of ribavirin in Atlantic salmon's (Salmo salar) muscle after oral administration in feed.

PubMed

San Martín, B; Muñoz, R; Cornejo, J; Martínez, M A; Araya-Jordán, C; Maddaleno, A; Anadón, A

2016-08-01

Ribavirin is an antiviral used in human medicine, but it has not been authorized for use in veterinary medicine although it is effective against infectious salmon anemia (ISA) virus, between others. In this study, we present a pharmacokinetic profile of ribavirin in Atlantic salmon (Salmo salar), efficacy prediction indexes, and the measure of its withdrawal time. To determine the pharmacokinetic profile, fishes were orally administered with a single ribavirin dose of 1.6 mg/kg bw, and then, plasma concentrations were measured at different times. From the time-vs.-concentration curve, Cmax = 413.57 ng/mL, Tmax  = 6.96 h, AUC = 21394.01 μg·h/mL, t1/2  = 81.61 h, and K10  = 0.0421/h were obtained. Ribavirin reached adequate concentrations during the pharmacokinetic study, with prediction indexes of Cmax /IC50  = 20.7, AUC/IC50  = 1069.7, and T>IC50  = 71 h, where IC is the inhibitory concentration 50%. For ribavirin depletion study, fishes were orally administered with a dairy dose of 1.6 mg/kg bw during 10 days. Concentrations were measured on edible tissue on different days post-treatment. A linear regression of the time vs. concentration was conducted, obtaining a withdrawal time of 1966 °C days. Results obtained reveal that the dose of 1.6 mg/kg bw orally administered is effective for ISA virus, originating a reasonable withdrawal period within the productive schedules of Atlantic salmon. © 2016 John Wiley & Sons Ltd.

Treating opioid dependence. Growing implications for primary care.

PubMed

Krantz, Mori J; Mehler, Philip S

2004-02-09

Almost 3 million Americans have abused heroin. The most effective treatment for this concerning epidemic is opioid replacement therapy. Although, from a historical perspective, acceptance of this therapy has been slow, growing evidence supports its efficacy. There are 3 approved medications for opioid maintenance therapy: methadone hydrochloride, levomethadyl acetate, and buprenorphine hydrochloride. Each has unique characteristics that determine its suitability for an individual patient. Cardiac arrhythmias have been reported with methadone and levomethadyl, but not with buprenorphine. Due to concerns about cardiac risk, levomethadyl use has declined and the product may ultimately be discontinued. These recent safety concerns, specifics about opioid detoxification and maintenance, and new federal initiatives were studied. Opioid detoxification has a role in both preventing acute withdrawal and maintaining long-term abstinence. Although only a minority of eligible patients are engaged in treatment, opioid maintenance therapy appears to offer the greatest public health benefits. There is growing interest in expanding treatment into primary care, allowing opioid addiction to be managed like other chronic illnesses. This model has gained wide acceptance in Europe and is now being implemented in the United States. The recent Drug Addiction Treatment Act enables qualified physicians to treat opioid-dependent patients with buprenorphine in an office-based setting. Mainstreaming opioid addiction treatment has many advantages; its success will depend on resolution of ethical and delivery system issues as well as improved and expanded training of physicians in addiction medicine.

Psychotropic drugs in opioid addicts on methadone treatment.

PubMed

Ferris, G N

1976-07-01

Psychotropic drug treatment of persons on methadone maintenance is discussed. Patients with clear target symptoms, such as anxiety, depression, or psychosis responded just as non-opioid addicts would to the major psychotropic agents. The minor tranquilizers are felt to be of doubtful value, and subject to abuse. Sleep disturbances cannot be treated by the usual means, as the drugs needed again are abused. However, chlorpromazine shows some promise here. Methods of drug delivery and goals of treatment must be adapted to the realities of this patient-group's characteristics, particularly anti-social traits, poor motivation and unreliability. Psychotropic drugs are unlikely to be of aid in multiple drug abusers, personality and character disorders, and opioid withdrawal. Four case histories are presented.

Investigational opioid antagonists for treating opioid-induced bowel dysfunction.

PubMed

Mozaffari, Shilan; Nikfar, Shekoufeh; Abdollahi, Mohammad

2018-03-01

Opioids have been highlighted for their role in pain relief among cancer and non-cancer patients. Novel agents have been investigated to reduce opioid-induced constipation (OIC) as the main adverse effect that may lead to treatment discontinuation. Development of peripherally acting mu-opioid receptor antagonists (PAMORA) has resulted in a novel approach to preserve the efficacy of pain control along with less OIC. Areas covered: Clinical evidence for investigational PAMORAs was reviewed and clinical trials on investigational agents to reduce OIC were included. TD-1211 is currently being evaluated in Phase II clinical trial. Oxycodone-naltrexone and ADL-5945 went through Phase III clinical trials, but have been discontinued. Expert opinion: There is a substantial need to develop agents with specific pharmacokinetic properties to meet the needs of patients with underlying diseases. Holding the efficacy of a medicine with the highest selectivity on targeted receptors and the least adverse effects is the main approach in upcoming investigations to improve patients' quality of life (QoL). Novel agents to reduce opioid-induced bowel dysfunction (OIBD) that do not reverse peripherally mediated pain analgesia are of great interest. Direct comparison of available agents in this field is lacking in the literature.

Benzodiazepines: a major component in unintentional prescription drug overdoses with opioid analgesics.

PubMed

Jann, Michael; Kennedy, William Klugh; Lopez, Gaylord

2014-02-01

The misuse and abuse of prescription medications in the United States continues to increase despite interventions by health care professionals, regulatory, and law enforcement agencies. Opioid analgesics are the leading class of prescription drugs that have caused unintentional overdose deaths. Benzodiazepines when taken alone are relatively safe agents in overdose. However, a 5-fold increase in deaths attributed to benzodiazepines occurred from 1999 to 2009. Emergency department visits related to opioid analgesics increased by 111% followed by benzodiazepines 89%. During 2003 to 2009, the 2 prescriptions drugs with the highest increase in death rates were oxycodone 264.6% and alprazolam 233.8%. Therefore, benzodiazepines have a significant impact on prescription drug unintentional overdoses second only to the opioid analgesics. The combination prescribing of benzodiazepines and opioid analgesics commonly takes place. The pharmacokinetic drug interactions between benzodiazepines and opioid analgesics are complex. The pharmacodynamic actions of these agents differ as their combined effects produce significant respiratory depression. Physician and pharmacy shopping by patients occurs, and prescription drug-monitoring programs can provide important information on benzodiazepine and opioid analgesic prescribing patterns and patient usage. Health care professionals need to inform patients and work closely with regulatory agencies and legislatures to stem the increasing fatalities from prescription drug unintentional overdoses.

Delta-Selective Glycopeptides Related to Enkephalin Produce Profound Analgesia with Reduced Side Effects in Mice

DTIC Science & Technology

2004-09-01

depression or the risk of overdose is particularly appealing. Further research needs to be completed in order to quantify the effects of the... fentanyl and other morphine-like analgesics on the warm water-induced tail- withdrawal reflex in rats. Jannsen, P.A.J.; Niemegeers, C.J.E.; Dorg, J.G.H...the delta opioid agonist BW373U86 and the mu opioid agonist fentanyl in mice. O’Neill, S.J.; Collins, M.A.; Pettit, H.O.; McNutt, R.W.; Chang, K.J. J

Intranasal Opioid Administration in Rhesus Monkeys: PET Imaging and Antinociception.

PubMed

Saccone, Phillip A; Lindsey, Angela M; Koeppe, Robert A; Zelenock, Kathy A; Shao, Xia; Sherman, Phillip; Quesada, Carole A; Woods, James H; Scott, Peter J H

2016-11-01

The goal of this study was to evaluate the effects of intranasally administered opioids in rhesus monkeys using the tail-withdrawal assay, and to correlate these effects with measures of receptor occupancy using positron emission tomography (PET) imaging. Initial experiments characterized the antinociceptive effects of intranasal (IN) fentanyl and buprenorphine relative to intramuscular (IM) injection. Fentanyl (0.010-0.032 mg/kg) and buprenorphine (0.1-1.0 mg/kg) produced dose-dependent increases in tail-withdrawal latency that did not differ between routes of delivery. The second experiment compared the ability of IN and intravenous (IV) naloxone (NLX) to block the antinociceptive effects IV fentanyl, and to measure receptor occupancy at equipotent doses of NLX using PET imaging. IN and IV NLX (0.0032-0.032 mg/kg) produced dose-dependent decreases in fentanyl-induced antinociception. Again, there was no difference observed in overall potency between routes. PET imaging showed that IV and IN NLX produced similar decreases in receptor occupancy as measured by [ 11 C]carfentanil blocking, although there was a trend for IV NLX to produce marginally greater occupancy changes. This study validated the first procedures to evaluate the IN effects of opioids in rhesus monkeys. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

42 CFR 8.22 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID... Adverse Action Regarding Withdrawal of Approval of an Accreditation Body § 8.22 Definitions. The following... requested a review of the suspension or proposed revocation, or (2) The accreditation body which has been...

42 CFR 8.22 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID... Adverse Action Regarding Withdrawal of Approval of an Accreditation Body § 8.22 Definitions. The following... requested a review of the suspension or proposed revocation, or (2) The accreditation body which has been...

Glial Attenuation With Ibudilast in the Treatment of Medication Overuse Headache: A Double-Blind, Randomized, Placebo-Controlled Pilot Trial of Efficacy and Safety.

PubMed

Johnson, Jacinta L; Kwok, Yuen H; Sumracki, Nicole M; Swift, James E; Hutchinson, Mark R; Johnson, Kirk; Williams, Desmond B; Tuke, Jonathon; Rolan, Paul E

2015-10-01

Medication overuse headache (MOH) is a condition bordering between a chronic pain condition and a substance dependence disorder. Activation of immunocompetent glial cells in the central nervous system has been linked to both pathological pain and drug addiction/reward. Preclinically, ibudilast attenuates glial activation and is able to reduce neuropathic pain and markers of substance dependence. We therefore hypothesized ibudilast would reduce headache burden and opioid analgesic requirements in patients with opioid overuse headache. To determine if treatment with ibudilast provides a greater reduction in headache index than placebo in MOH patients consuming opioids. Participants with MOH who were using opioids were randomized via computer-generated code to ibudilast 40 mg or placebo twice daily for 8 weeks in a double-blind, parallel groups study. Before randomization participants completed a 4-week baseline headache diary. During treatment, headache diary data collection continued and participants attended 4 study visits during which quantitative sensory testing was performed. Blood samples for immune biomarker analyses were collected before and after treatment in a subgroup of participants. Thirty-four participants were randomized, 13 of 15 randomized to ibudilast and 17 of 19 randomized to placebo completed treatment. Ibudilast was generally well-tolerated with mild, transient nausea reported as the most common adverse event (66.7% vs 10.5% in placebo group). Results are shown as mean (SD). At the end of treatment no differences in the primary outcome average daily headache index (placebo 62 [44] vs ibudilast 77 [72] groups, difference -15, CI -65 to 35 h × numerical rating scale), or secondary outcomes headache frequency (placebo 23 [8.1] vs ibudilast 24.5 [6.2], difference -1.5, CI -7.7 to 4.8 days/month) and opioid intake (placebo 20.6 [43] vs ibudilast 19 [24.3], difference 1.6, CI -31.5 to 34.8 mg morphine equivalent) were observed between placebo and ibudilast groups. Using the current dosing regimen, ibudilast does not improve headache or reduce opioid use in patients with MOH without mandated opioid withdrawal. However, it would be of interest to determine in future trials if ibudilast is able to improve ease of withdrawal during a forced opioid down-titration when incorporated into an MOH detoxification program. © 2015 American Headache Society.

A Combination of Buprenorphine and Naltrexone Blocks Compulsive Cocaine Intake in Rodents Without Producing Dependence

PubMed Central

Wee, Sunmee; Vendruscolo, Leandro F.; Misra, Kaushik K.; Schlosburg, Joel E.; Koob, George F.

2012-01-01

Buprenorphine, a synthetic opioid that acts at both μ and κ opioid receptors, can decrease cocaine use in individuals with opioid addiction. However, the potent agonist action of buprenorphine at μ opioid receptors raises its potential for creating opioid dependence in non–opioid-dependent cocaine abusers. Here, we tested the hypothesis that a combination of buprenorphine and naltrexone (a potent μ opioid antagonist with weaker δ and κ antagonist properties) could block compulsive cocaine self-administration without producing opioid dependence. The effects of buprenorphine and various doses of naltrexone on cocaine self-administration were assessed in rats that self-administered cocaine under conditions of either short access (noncompulsive cocaine seeking) or extended access (compulsive cocaine seeking). Buprenorphine alone reproducibly decreased cocaine self-administration. Although this buprenorphine-alone effect was blocked in a dose-dependent manner by naltrexone in both the short-access and the extended-access groups, the combination of the lowest dose of naltrexone with buprenorphine blocked cocaine self-administration in the extended-access group but not in the short-access group. Rats given this low dose of naltrexone with buprenorphine did not exhibit the physical opioid withdrawal syndrome seen in rats treated with buprenorphine alone, and naltrexone at this dose did not block κ agonist–induced analgesia. The results suggest that the combination of buprenorphine and naltrexone at an appropriate dosage decreases compulsive cocaine self-administration with minimal liability to produce opioid dependence and may be useful as a treatment for cocaine addiction. PMID:22875830

A combination of buprenorphine and naltrexone blocks compulsive cocaine intake in rodents without producing dependence.

PubMed

Wee, Sunmee; Vendruscolo, Leandro F; Misra, Kaushik K; Schlosburg, Joel E; Koob, George F

2012-08-08

Buprenorphine, a synthetic opioid that acts at both μ and κ opioid receptors, can decrease cocaine use in individuals with opioid addiction. However, the potent agonist action of buprenorphine at μ opioid receptors raises its potential for creating opioid dependence in non-opioid-dependent cocaine abusers. Here, we tested the hypothesis that a combination of buprenorphine and naltrexone (a potent μ opioid antagonist with weaker δ and κ antagonist properties) could block compulsive cocaine self-administration without producing opioid dependence. The effects of buprenorphine and various doses of naltrexone on cocaine self-administration were assessed in rats that self-administered cocaine under conditions of either short access (noncompulsive cocaine seeking) or extended access (compulsive cocaine seeking). Buprenorphine alone reproducibly decreased cocaine self-administration. Although this buprenorphine-alone effect was blocked in a dose-dependent manner by naltrexone in both the short-access and the extended-access groups, the combination of the lowest dose of naltrexone with buprenorphine blocked cocaine self-administration in the extended-access group but not in the short-access group. Rats given this low dose of naltrexone with buprenorphine did not exhibit the physical opioid withdrawal syndrome seen in rats treated with buprenorphine alone, and naltrexone at this dose did not block κ agonist-induced analgesia. The results suggest that the combination of buprenorphine and naltrexone at an appropriate dosage decreases compulsive cocaine self-administration with minimal liability to produce opioid dependence and may be useful as a treatment for cocaine addiction.

International patent applications for non-injectable naloxone for opioid overdose reversal: Exploratory search and retrieve analysis of the PatentScope database.

PubMed

McDonald, Rebecca; Danielsson Glende, Øyvind; Dale, Ola; Strang, John

2018-02-01

Non-injectable naloxone formulations are being developed for opioid overdose reversal, but only limited data have been published in the peer-reviewed domain. Through examination of a hitherto-unsearched database, we expand public knowledge of non-injectable formulations, tracing their development and novelty, with the aim to describe and compare their pharmacokinetic properties. (i) The PatentScope database of the World Intellectual Property Organization was searched for relevant English-language patent applications; (ii) Pharmacokinetic data were extracted, collated and analysed; (iii) PubMed was searched using Boolean search query '(nasal OR intranasal OR nose OR buccal OR sublingual) AND naloxone AND pharmacokinetics'. Five hundred and twenty-two PatentScope and 56 PubMed records were identified: three published international patent applications and five peer-reviewed papers were eligible. Pharmacokinetic data were available for intranasal, sublingual, and reference routes. Highly concentrated formulations (10-40 mg mL -1 ) had been developed and tested. Sublingual bioavailability was very low (1%; relative to intravenous). Non-concentrated intranasal spray (1 mg mL -1 ; 1 mL per nostril) had low bioavailability (11%). Concentrated intranasal formulations (≥10 mg mL -1 ) had bioavailability of 21-42% (relative to intravenous) and 26-57% (relative to intramuscular), with peak concentrations (dose-adjusted C max  = 0.8-1.7 ng mL -1 ) reached in 19-30 min (t max ). Exploratory analysis identified intranasal bioavailability as associated positively with dose and negatively with volume. We find consistent direction of development of intranasal sprays to high-concentration, low-volume formulations with bioavailability in the 20-60% range. These have potential to deliver a therapeutic dose in 0.1 mL volume. [McDonald R, Danielsson Glende Ø, Dale O, Strang J. International patent applications for non-injectable naloxone for opioid overdose reversal: Exploratory search and retrieve analysis of the PatentScope database. Drug Alcohol Rev 2017;00:000-000]. © 2017 Australasian Professional Society on Alcohol and other Drugs.

Co-administration of delta- and mu-opioid receptor agonists promotes peripheral opioid receptor function

PubMed Central

Schramm, Cicely L.; Honda, Christopher N.

2010-01-01

Enhancement of peripheral opioid analgesia following tissue injury or inflammation in animal models is well-documented, but clinical results of peripheral opioid therapy remain inconsistent. Previous studies in the central nervous system have shown that co-administration of μ- and δ-opioid receptor agonists can enhance analgesic outcomes; however, less is known about the functional consequences of opioid receptor interactions in the periphery. The present study examines the effects of intraplantar injection of the μ- and δ-opioid receptor agonists, morphine and deltorphin, alone and in combination on behavioral tests of nociception in naïve rats and on potassium-evoked release of CGRP from sciatic nerves of naïve rats. Neither drug alone affected nociceptive behaviors or CGRP release. Two separate measures of mechanical nociceptive sensitivity remained unchanged after co-administration of the two drugs. In contrast, when deltorphin was co-injected with morphine, dose-dependent and peripherally-restricted increases in paw withdrawal latencies to radiant heat were observed. Similarly, concentration-dependent inhibition of CGRP release was observed when deltorphin and morphine were administered in sequence prior to potassium stimulation. However, no inhibition was observed when morphine was administered prior to deltorphin. All combined opioid effects were blocked by co-application of antagonists. Deltorphin exposure also enhanced the in vivo and in vitro effects of another μ-opioid receptor agonist, DAMGO. Together, these results suggest that under normal conditions, δ-opioid receptor agonists enhance the effect of μ-opioid receptor agonists in the periphery, and local co-administration of δ- and μ-opioid receptor agonists may improve results of peripheral opioid therapy for the treatment of pain. PMID:20970925

Baclofen prevents the elevated plus maze behavior and BDNF expression during naloxone precipitated morphine withdrawal in male and female mice.

PubMed

Pedrón, Valeria T; Varani, André P; Balerio, Graciela N

2016-05-01

In previous studies we have shown that baclofen, a selective GABAB receptor agonist, prevents the somatic expression and reestablishes the dopamine and μ-opioid receptors levels, modified during naloxone-precipitated morphine withdrawal syndrome in male and female mice. There are no previous reports regarding sex differences in the elevated plus maze (EPM) and the expression of BDNF in morphine-withdrawn mice. The present study analyses the behavioral and biochemical variations during morphine withdrawal in mice of both sexes, and whether these variations are prevented with baclofen. Swiss-Webster albino prepubertal mice received morphine (2 mg/kg, i.p.) twice daily, for 9 consecutive days. On the 10th day, one group of morphine-treated mice received naloxone (opioid receptor antagonist; 6 mg/kg, i.p.) 1 h after the last dose of morphine to precipitate withdrawal. A second group received baclofen (2 mg/kg, i.p.) before naloxone administration. The EPM behavior was measured during 15 min after naloxone injection. The expression of BDNF-positive cells was determined by immunohistochemistry. Withdrawn male mice showed a higher percentage of time spent and number of entries to the open arms compared to withdrawn female mice. Baclofen prevented this behavior in both sexes. BDNF expression decreased in the AcbC, BNST, CeC, and CA3 of the hippocampus while increased in the BLA of morphine withdrawn male. Baclofen pretreatment prevented the BDNF expression observed in morphine withdrawn male mice in all the brain areas studied except in the CeC. Baclofen prevention of the EPM behavior associated to morphine withdrawal could be partially related to changes in BDNF expression. © 2016 Wiley Periodicals, Inc.

Altering ethanol pharmacokinetics to treat alcohol use disorder: Can you teach an old dog new tricks?

PubMed

Haass-Koffler, Carolina L; Akhlaghi, Fatemeh; Swift, Robert M; Leggio, Lorenzo

2017-07-01

Disulfiram was the first pharmacotherapy approved to treat alcohol use disorder in the 1950s. Disulfiram alters ethanol pharmacokinetics and causes uncomfortable reactions (e.g. headache, tachycardia, nausea, flushing and hypotension) when alcohol is consumed. Subsequently, a better understanding of the neurobiological pathways involved in alcohol use disorder led to the development of other medications (e.g. naltrexone and acamprosate). These neurobiological-based medications act on alcohol use disorder-related phenotypes including craving, stress, and/or withdrawal. The original approach to treat alcohol use disorder, by altering ethanol pharmacokinetics has been much less investigated. Recent research on ethanol pharmacokinetics has shed light on the mechanisms of action underlying alcohol use disorder and how some medications that alter ethanol pharmacokinetics may be helpful in treating alcohol use disorder. This review summarizes and discusses the complex pharmacokinetics of ethanol, and proposes that altering ethanol pharmacokinetics via novel pharmacological approaches may be a viable approach to treat alcohol use disorder.

Evaluation of Analgesic Activity of Papaver libanoticum Extract in Mice: Involvement of Opioids Receptors

PubMed Central

El-Mallah, Ahmed; Aboul-Ela, Maha; Ellakany, Abdalla

2017-01-01

Papaver libanoticum is an endemic plant to Lebanese region (family Papaveraceae) that has not been investigated before. The present study aimed to explore the analgesic activity of dried ethanolic extract of Papaver libanoticum (PLE) using tail flick, hot plate, and acetic acid induced writhing models in mice. The involvement of opioid receptors in the analgesic mechanism was investigated using naloxone antagonism. Results demonstrated that PLE exhibited a potent dose dependent analgesic activity in all tested models for analgesia. The analgesic effect involved activation of opioid receptors in the central nervous system, where both spinal and supraspinal components might be involved. The time course for analgesia revealed maximum activity after three hours in both tail flick and hot plate methods, which was prolonged to 24 hours. Metabolites of PLE could be responsible for activation of opioid receptors. The EC50 of PLE was 79 and 50 mg/kg in tail flick and hot plate tests, respectively. The total coverage of analgesia by PLE was double that of morphine in both tests. In conclusion, PLE proved to have opioid agonistic activity with a novel feature of slow and prolonged effect. The present study could add a potential tool in the armaments of opioid drugs as a natural potent analgesic and for treatment of opioid withdrawal syndrome. PMID:28280516

Evaluation of Analgesic Activity of Papaver libanoticum Extract in Mice: Involvement of Opioids Receptors.

PubMed

Hijazi, Mohamad Ali; El-Mallah, Ahmed; Aboul-Ela, Maha; Ellakany, Abdalla

2017-01-01

Papaver libanoticum is an endemic plant to Lebanese region (family Papaveraceae) that has not been investigated before. The present study aimed to explore the analgesic activity of dried ethanolic extract of Papaver libanoticum (PLE) using tail flick, hot plate, and acetic acid induced writhing models in mice. The involvement of opioid receptors in the analgesic mechanism was investigated using naloxone antagonism. Results demonstrated that PLE exhibited a potent dose dependent analgesic activity in all tested models for analgesia. The analgesic effect involved activation of opioid receptors in the central nervous system, where both spinal and supraspinal components might be involved. The time course for analgesia revealed maximum activity after three hours in both tail flick and hot plate methods, which was prolonged to 24 hours. Metabolites of PLE could be responsible for activation of opioid receptors. The EC50 of PLE was 79 and 50 mg/kg in tail flick and hot plate tests, respectively. The total coverage of analgesia by PLE was double that of morphine in both tests. In conclusion, PLE proved to have opioid agonistic activity with a novel feature of slow and prolonged effect. The present study could add a potential tool in the armaments of opioid drugs as a natural potent analgesic and for treatment of opioid withdrawal syndrome.

Utilizing buprenorphine–naloxone to treat illicit and prescription-opioid dependence

PubMed Central

Mauger, Sofie; Fraser, Ronald; Gill, Kathryn

2014-01-01

Objectives To review current evidence on buprenorphine–naloxone (bup/nx) for the treatment of opioid-use disorders, with a focus on strategies for clinical management and office-based patient care. Quality of evidence Medline and the Cochrane Database of Systematic Reviews were searched. Consensus reports, guidelines published, and other authoritative sources were also included in this review. Apart from expert guidelines, data included in this review constitute level 1 evidence. Findings Bup/nx is a partial μ-opioid agonist combined with the opioid antagonist naloxone in a 4:1 ratio. It has a lower abuse potential, carries less stigma, and allows for more flexibility than methadone. Bup/nx is indicated for both inpatient and ambulatory medically assisted withdrawal (acute detoxification) and long-term substitution treatment (maintenance) of patients who have a mild-to-moderate physical dependence. A stepwise long-term substitution treatment with regular monitoring and follow-up assessment is usually preferred, as it has better outcomes in reducing illicit opioid use, minimizing concomitant risks such as human immunodeficiency virus and hepatitis C transmission, retaining patients in treatment and improving global functioning. Conclusion Bup/nx is safe and effective for opioid detoxification and substitution treatment. Its unique pharmaceutical properties make it particularly suitable for office-based maintenance treatment of opioid-use disorder. PMID:24741316

Effects of the NMDA receptor antagonist, D-CPPene, on sensitization to the operant decrement produced by naloxone in morphine-treated rats.

PubMed

Bespalov, A Y; Medvedev, I O; Sukhotina, I A; Zvartau, E E

2001-04-01

Sensitization to the rate-decreasing effects of opioid antagonists induced by acute pretreatment with opioid agonists has been suggested to reflect initial changes in opioid systems that underlie physical dependence. Glutamate receptors are implicated in the development and expression of opioid dependence, and antagonists acting at the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors have been shown repeatedly to attenuate the severity of opioid withdrawal. The present study evaluated the ability of a competitive NMDA receptor antagonist, D-CPPene (SDZ EAA 494; 3-(2-carboxypiperazin-4-yl)-1-propenyl-1-phosphonic acid), to affect morphine-induced sensitization to naloxone in rats trained to lever-press on a multiple-trial, fixed-ratio 10 schedule of food reinforcement. D-CPPene (0.3-3 mg/kg) was administered either 4 h or 30 min prior to the test session. Morphine (10 mg/kg) or its vehicle was administered 4 h before naloxone challenge (0.3-3 mg/kg). D-CPPene failed to prevent morphine-induced potentiation of the naloxone-produced decrement in operant performance. Thus, these results suggest that agonist-induced sensitization to behavioral effects of opioid antagonists may be insensitive to NMDA receptor blockade.

The effects of kratom on restraint-stress-induced analgesia and its mechanisms of action.

PubMed

Vázquez López, José Luis; Schild, Lorenz; Günther, Thomas; Schulz, Stefan; Neurath, Hartmud; Becker, Axel

2017-06-09

Mitragyna speciosa and its extracts are called kratom (dried leaves, extract). They contain several alkaloids with an affinity for different opioid receptors. They are used in traditional medicine for the treatment of different diseases, as a substitute by opiate addicts, and to mitigate opioid withdrawal symptoms. Apart from their medical properties, they are used to enhance physical endurance and as a means of overcoming stress. The aim of this study was to determine the mechanisms underlying the effects of kratom on restraint-stress-induced analgesia which occurs during or following exposure to a stressful or fearful stimulus. To gain further insights into the action of kratom on stress, we conducted experiments using restraint stress as a test system and stress-induced analgesia as a test parameter. Using transgenic mu opioid-receptor (MOR) deficient mice, we studied the involvement of this receptor type. We used nor-binaltorphimine (BNT), an antagonist at kappa opioid receptors (KOR), to study functions of this type of receptor. Membrane potential assay was also employed to measure the intrinsic activity of kratom in comparison to U50,488, a highly selective kappa agonist. Treatment with kratom diminished stress-induced analgesia in wildtype and MOR knockout animals. Pretreatment of MOR deficient mice with BNT resulted in similar effects. In comparison to U50,488, kratom exhibited negligible intrinsic activity at KOR alone. The results suggest that the use of kratom as a pharmacological tool to mitigate withdrawal symptoms is related to its action on KOR. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Association between the DRD2 A1 allele and response to methadone and buprenorphine maintenance treatments.

PubMed

Barratt, Daniel T; Coller, Janet K; Somogyi, Andrew A

2006-06-05

The TaqI A polymorphism (A(1)) of the dopamine D(2) receptor gene (DRD2), although not a specific predictor of opioid dependence, has been strongly associated with high levels of prior heroin use and poor treatment outcomes among methadone maintenance patients. The aims of this study were to confirm these findings via a retrospective analysis of A(1) allele frequency in methadone (n = 46) and buprenorphine (n = 25) patients, and non-opioid-dependent controls (n = 95). Subjects were genotyped at the DRD2 TaqI A locus using PCR amplification followed by TaqI restriction enzyme digestion and gel electrophoresis. For methadone and buprenorphine subjects, heroin use (prior to treatment), treatment outcomes, and withdrawal occurrence were determined from comprehensive case notes. No significant differences in A(1) allele frequency (%) were observed between: methadone (19.6%), buprenorphine (18.0%), and control (17.9%) groups (P > 0.7); successful and poor treatment outcome groups, methadone: 20.0% and 19.2%, respectively (P = 1.0); buprenorphine: 18.4% and 20.0%, respectively (P = 1.0). Also, there were no significant relationships between TaqI A genotype and prior heroin use (P = 0.47). However, among the successful methadone subjects, significantly fewer A(1) allele carriers experienced withdrawal than non-A(1) carriers (P = 0.04). In conclusion, the DRD2 genotype effects did not affect opioid maintenance treatment outcomes. This suggests the need for a further prospective investigation into the role of the DRD2 A(1) allele in heroin use and response to maintenance pharmacotherapies for opioid dependence.

Psychological and physiological stress negatively impacts early engagement and retention of opioid-dependent individuals on methadone maintenance

PubMed Central

Jaremko, Kellie M.; Sterling, Robert C.; Van Bockstaele, Elisabeth J.

2014-01-01

The present study investigated whether psychological and/or physiological measures of stress would impede induction onto methadone maintenance and predict early (<6 months) discontinuation. Compared with controls, opioid-dependent subjects displayed increased distress on the perceived stress scale (PSS) and post-traumatic stress disorder checklist (PCLC); 60% exhibited abnormal cortisol. Addiction severity index (ASI), drug-use, and stress indices explained between 17–37% of the variance in engagement including attendance, opioid abstinence, and methadone stabilization. Participants who discontinued treatment displayed poor engagement, abnormal cortisol, elevated withdrawal symptoms, higher distress, and increased ongoing opioid use versus compliant individuals. Discontinuation was initially related to drug-use severity; however, by 6 months, retention depended primarily upon cortisol abnormalities, which increased an individual’s discontinuation risk by 7.7-fold. These findings support admission screening with the ASI/cortisol for drop out, and stress/drug-use indices for engagement that together may enable clinically-relevant early recognition and interventions for prevention of stress-induced relapse in opioid-dependent populations. PMID:25239858

Psychological and physiological stress negatively impacts early engagement and retention of opioid-dependent individuals on methadone maintenance.

PubMed

Jaremko, Kellie M; Sterling, Robert C; Van Bockstaele, Elisabeth J

2015-01-01

The present study investigated whether psychological and/or physiological measures of stress would impede induction onto methadone maintenance and predict early (<6 months) discontinuation. Compared with controls, opioid-dependent subjects displayed increased distress on the perceived stress scale (PSS) and post-traumatic stress disorder checklist (PCLC); 60% exhibited abnormal cortisol. Addiction severity index (ASI), drug-use, and stress indices explained between 17 and 37% of the variance in engagement including attendance, opioid abstinence, and methadone stabilization. Participants who discontinued treatment displayed poor engagement, abnormal cortisol, elevated withdrawal symptoms, higher distress, and increased ongoing opioid use versus compliant individuals. Discontinuation was initially related to drug-use severity; however, by 6 months, retention depended primarily upon cortisol abnormalities, which increased an individual's discontinuation risk by 7.7-fold. These findings support admission screening with the ASI/cortisol for drop out, and stress/drug-use indices for engagement that together may enable clinically-relevant early recognition and interventions for prevention of stress-induced relapse in opioid-dependent populations. Copyright © 2014 Elsevier Inc. All rights reserved.

Complications of oral exposure to fentanyl transdermal delivery system patches.

PubMed

Prosser, Jane M; Jones, Brent E; Nelson, Lewis

2010-12-01

Fentanyl is a synthetic opioid available therapeutically as an intravenous, transbucal, or transdermal preparation. It is also used as a drug of abuse through a variety of different methods, including the oral abuse of transdermal fentanyl patches. This is a series of patients with oral fentanyl patch exposure reported to our center and represents the first series of oral fentanyl patch exposures collected outside of the postmortem setting. In this series, we examined the New York Poison Control Center database for all cases of oral abuse of fentanyl reported between January 2000 and April 2008. Twenty cases were reported, nine were asymptomatic or had symptoms of opioid withdrawal; 11 had symptoms of opioid intoxication. Eight patients were administered naloxone and all showed improvement in clinical status. Only one case resulted in a confirmed fatality-this patient had an orally adherent patch discovered at intubation. Oral exposure may result in life-threatening toxicity. Patients should be closely assessed and monitored for the opioid toxidrome, and if symptomatic, should be managed with opioid antagonists and ventilatory support.

Parallel Synthesis of Hexahydrodiimidazodiazepines Heterocyclic Peptidomimetics and Their in Vitro and in Vivo Activities at μ (MOR), δ (DOR), and κ (KOR) Opioid Receptors.

PubMed

Eans, Shainnel O; Ganno, Michelle L; Mizrachi, Elisa; Houghten, Richard A; Dooley, Colette T; McLaughlin, Jay P; Nefzi, Adel

2015-06-25

In the development of analgesics with mixed-opioid agonist activity, peripherally selective activity is expected to decrease side effects, minimizing respiratory depression and reinforcing properties generating significantly safer analgesic therapeutics. We synthesized diazaheterocyclics from reduced tripeptides. In vitro screening with radioligand competition binding assays demonstrated variable affinity for μ (MOR), δ (DOR), and κ (KOR) opioid receptors across the series, with the diimidazodiazepine 14 (2065-14) displaying good affinity for DOR and KOR. Central (icv), intraperitoneal (ip), or oral (po) administration of 14 produced dose-dependent, opioid-receptor mediated antinociception in the mouse, as determined from a 55 °C warm-water tail-withdrawal assay. Only trace amounts of compound 14 was found in brain up to 90 min later, suggesting poor BBB penetration and possible peripherally restricted activity. Central administration of 14 did not produce locomotor effects, acute antinociceptive tolerance, or conditioned-place preference or aversion. The data suggest these diazaheterocyclic mixed activity opioid receptor agonists may hold potential as new analgesics with fewer liabilities of use.

Mu-opioid receptor (A118G) single-nucleotide polymorphism affects alfentanil requirements for extracorporeal shock wave lithotripsy: a pharmacokinetic-pharmacodynamic study.

PubMed

Ginosar, Y; Davidson, E M; Meroz, Y; Blotnick, S; Shacham, M; Caraco, Y

2009-09-01

There are diverse reports concerning the single-nucleotide polymorphism (SNP) A118G in the gene coding for the mu-opioid receptor. This study assessed pharmacokinetic-pharmacodynamic relationships in patients with acute pain (water-immersed extracorporeal shock wave lithotripsy). Ninety-nine patients (ASA I-II, age 18-70) were assessed in this prospective observational study. Blinding was achieved by determining genotype only after the procedure. I.V. alfentanil was administered by patient-controlled administration (loading dose, 10 microg kg(-1); continuous infusion, 20 microg kg(-1) h(-1); bolus, 3 microg kg(-1); lockout time, 1 min); no other analgesic or sedating medication was used. The allelic frequency was 15.2% in our population. The G118 SNP (AG/GG) was associated with a 27% increase in plasma alfentanil concentration (P=0.034), a 54% increase in alfentanil dose (P=0.009), a 47% increase in dose per kg body weight (P=0.004), a 55% increase in dose per kg corrected for stimulus intensity (P=0.002), a 112% increase in the numbers of attempted boluses (P=0.015), a 79% increase in the numbers of successful boluses (P=0.013), and a 153% increase in the numbers of failed boluses (P=0.042). Despite the increased alfentanil self-administration, the G118 SNP was associated with a 52% increase in verbal analogue pain scores over the same period of time (P=0.047). We demonstrated increased opioid requirement for alfentanil in patients with the G118 SNP, who self-administered a higher dose, achieved higher plasma concentration, and yet complained of more severe pain. This observation suggests that G118 SNP impairs the analgesic response to opioids.

Pharmacokinetics and Analgesic Effects of Methadone in Children and Adults with Sickle Cell Disease

PubMed Central

Horst, Jennifer; Frei-Jones, Melissa; Deych, Elena; Shannon, William; Kharasch, Evan D.

2017-01-01

Background Vaso-occlusive episodes (VOE) are a significant source of morbidity among children and adults with sickle cell disease (SCD). There is little information on methadone use for SCD pain. This investigation evaluated methadone pharmacokinetics in children and adults with SCD, with a secondary aim to assess pain relief and opioid consumption. Procedure Participants included children (<18 yr) and adults with a VOE requiring hospitalization. Patients were randomly assigned to receive standard care (opioid patient controlled analgesia; control group) or one dose of intravenous methadone (0.1–0.125 mg/kg) in addition to standard care (methadone group). Venous methadone and metabolite concentrations were measured. Pain scores, pain relief scores, and opioid consumption were recorded. Results Twenty-four children (12 methadone, 12 controls) and twenty-three adults (11 methadone, 12 controls) were studied. In children, the half-life of R-and S-methadone enantiomers was 34±16 and 24±9 hr, respectively. In adults, R- and S-methadone half-lives were 52±17 and 38±12 hr. Pain scores were lower (p=0.002) and pain relief scores were higher (p=0.0396) in children receiving methadone vs controls. There was no difference in pain scores and pain relief in adults receiving methadone vs controls. There was no difference in opioid consumption between methadone and control groups, in both adults and children. Conclusions Intravenous methadone disposition in children and adults with SCD was comparable to subjects without SCD from prior studies. Methadone produced more pain relief than standard care in children with SCD. Higher methadone doses may be more effective and should be evaluated in both children and adults with SCD. PMID:27572136

Pharmacokinetics of hydrocodone/acetaminophen combination product in children ages 6-17 with moderate to moderately severe postoperative pain.

PubMed

Liu, Wei; Dutta, Sandeep; Kearns, Greg; Awni, Walid; Neville, Kathleen A

2015-02-01

Lortab® Elixir, a proprietary combination product containing hydrocodone and acetaminophen, is approved in the US for the treatment of moderate to moderately severe pain in children. Despite this approval, pediatric pharmacokinetic data using this product have not been previously published. Using a single-dose open-label study approach, we evaluated the pharmacokinetics, tolerability, and safety of this product in 17 healthy children 6-17 years of age. Results showed that the body weight-normalized oral clearance (L/h/kg) of hydrocodone and acetaminophen were 42% and 27% higher, respectively when compared to data from healthy adults. This suggests that a higher mg/kg dose would be required in children to achieve exposures similar to adults. We found adjustment of hydrocodone and acetaminophen dose by body surface area to be more optimal than body weight-based dose adjustments for achieving similar systemic exposure in children and adults. However, body weight-based hydrocodone and acetaminophen dosing regimens provided close approximation of adult exposures in pediatric patients with approximately 22% to 24% lower hydrocodone and acetaminophen dose/BW-normalized AUC in pediatric patients compared to adults. Finally, the adverse event profile in our pediatric cohort was consistent with that expected of opioid-naive subjects receiving opioid-combination therapy. © 2014, The American College of Clinical Pharmacology.

Positive allosteric modulators of the μ-opioid receptor: a novel approach for future pain medications

PubMed Central

Burford, N T; Traynor, J R; Alt, A

2015-01-01

Morphine and other agonists of the μ-opioid receptor are used clinically for acute and chronic pain relief and are considered to be the gold standard for pain medication. However, these opioids also have significant side effects, which are also mediated via activation of the μ-opioid receptor. Since the latter half of the twentieth century, researchers have sought to tease apart the mechanisms underlying analgesia, tolerance and dependence, with the hope of designing drugs with fewer side effects. These efforts have revolved around the design of orthosteric agonists with differing pharmacokinetic properties and/or selectivity profiles for the different opioid receptor types. Recently, μ-opioid receptor-positive allosteric modulators (μ-PAMs) were identified, which bind to a (allosteric) site on the μ-opioid receptor separate from the orthosteric site that binds an endogenous agonist. These allosteric modulators have little or no detectable functional activity when bound to the receptor in the absence of orthosteric agonist, but can potentiate the activity of bound orthosteric agonist, seen as an increase in apparent potency and/or efficacy of the orthosteric agonist. In this review, we describe the potential advantages that a μ-PAM approach might bring to the design of novel therapeutics for pain that may lack the side effects currently associated with opioid therapy. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2 PMID:24460691

New mechanisms and perspectives in nicotine withdrawal

PubMed Central

Jackson, K.J.; Muldoon, P.P.; De Biasi, M.; Damaj, M.I.

2014-01-01

Diseases associated with tobacco use constitute a major health problem worldwide. Upon cessation of tobacco use, an unpleasant withdrawal syndrome occurs in dependent individuals. Avoidance of the negative state produced by nicotine withdrawal represents a motivational component that promotes continued tobacco use and relapse after smoking cessation. With the modest success rate of currently available smoking cessation therapies, understanding mechanisms involved in the nicotine withdrawal syndrome are crucial for developing successful treatments. Animal models provide a useful tool for examining neuroadaptative mechanisms and factors influencing nicotine withdrawal, including sex, age, and genetic factors. Such research has also identified an important role for nicotinic receptor subtypes in different aspects of the nicotine withdrawal syndrome (e.g., physical vs. affective signs). In addition to nicotinic receptors, the opioid and endocannabinoid systems, various signal transduction pathways, neurotransmitters, and neuropeptides have been implicated in the nicotine withdrawal syndrome. Animal studies have informed human studies of genetic variants and potential targets for smoking cessation therapies. Overall, the available literature indicates that the nicotine withdrawal syndrome is complex, and involves a range of neurobiological mechanisms. As research in nicotine withdrawal progresses, new pharmacological options for smokers attempting to quit can be identified, and treatments with fewer side effects that are better tailored to the unique characteristics of patients may become available. PMID:25433149

Buprenorphine: revisiting the efficacy of transdermal delivery system.

PubMed

Kitzmiller, Joseph P; Barnett, Christopher J; Steiner, Nathan S; Stoicea, Nicoleta; Kamar, Nawal; Luzum, Jasmine A; Mikulik, Eduard; Bergese, Sergio D

2015-01-01

Buprenorphine is a lipid-soluble pharmaceutic used in the management of chronic pain. It is a partial agonist at μ-opioid receptors, an antagonist at κ-opioid receptors, an agonist at δ-opioid receptors and a partial agonist at ORL-1 (nociceptin) receptors. An extensive literature search, including Google Scholar and Pubmed database, was conducted. Terms including and associated to 'efficacy of transdermal buprenorphine' were utilized to procure contemporary research articles in order to evaluate and compare the transdermal buprenorphine patch to commonly used traditional pain management medications. Transdermal buprenorphine has demonstrated better efficacy than conventional pain management pharmacotherapies. Side effects were similar to those associated with other opioids and included headache, dizziness, somnolence, constipation, dry mouth, nausea, vomiting, pruritus and erythema. Similar to transdermal delivery systems used with other medication, transdermal buprenorphine was associated with application-site pruritus and application-site reactions. Transdermal buprenorphine has significant potential for managing chronic pain. In addition to increased convenience and efficacy, advantages of transdermal buprenorphine include decreased tolerance and decreased withdrawal.

Nicotine anxiogenic and rewarding effects are decreased in mice lacking beta-endorphin.

PubMed

Trigo, José M; Zimmer, Andreas; Maldonado, Rafael

2009-06-01

The endogenous opioid system plays an important role in the behavioral effects of nicotine. Thus, micro-opioid receptor and the endogenous opioids derived from proenkephalin are involved in the central effects of nicotine. However, the role played by the different endogenous opioid peptides in the acute and chronic effects of nicotine remains to be fully established. Mice lacking beta-endorphin were acutely injected with nicotine at different doses to evaluate locomotor, anxiogenic and antinociceptive responses. The rewarding properties of nicotine were evaluated by using the conditioned place-preference paradigm. Mice chronically treated with nicotine were acutely injected with mecamylamine to study the behavioral expression of nicotine withdrawal. Mice lacking beta-endorphin exhibited a spontaneous hypoalgesia and hyperlocomotion and a reduction on the anxiogenic and rewarding effects induced by nicotine. Nicotine induced similar antinociception and hypolocomotion in both genotypes and no differences were found in the development of physical dependence. The dissociation between nicotine rewarding properties and physical dependence suggests a differential implication of beta-endorphin in these addictive related responses.

Interactions between recreational drugs and antiretroviral agents.

PubMed

Antoniou, Tony; Tseng, Alice Lin-In

2002-10-01

To summarize existing data regarding potential interactions between recreational drugs and drugs commonly used in the management of HIV-positive patients. Information was obtained via a MEDLINE search (1966-August 2002) using the MeSH headings human immunodeficiency virus, drug interactions, cytochrome P450, medication names commonly prescribed for the management of HIV and related opportunistic infections, and names of commonly used recreational drugs. Abstracts of national and international conferences, review articles, textbooks, and references of all articles were also reviewed. Literature on pharmacokinetic interactions was considered for inclusion. Pertinent information was selected and summarized for discussion. In the absence of specific data, prediction of potential clinically significant interactions was based on pharmacokinetic and pharmacodynamic properties. All protease inhibitors (PIs) and nonnucleoside reverse transcriptase inhibitors are substrates and potent inhibitors or inducers of the cytochrome P450 system. Many classes of recreational drugs, including benzodiazepines, amphetamines, and opioids, are also metabolized by the liver and can potentially interact with antiretrovirals. Controlled interaction studies are often not available, but clinically significant interactions have been observed in a number of case reports. Overdoses secondary to interactions between the "rave" drugs methylenedioxymethamphetamine (MDMA) or gamma-hydroxybutyrate (GHB) and PIs have been reported. PIs, particularly ritonavir, may also inhibit metabolism of amphetamines, ketamine, lysergic acid diethylmide (LSD), and phencyclidine (PCP). Case series and pharmacokinetic studies suggest that nevirapine and efavirenz induce methadone metabolism, which may lead to symptoms of opiate withdrawal. A similar interaction may exist between methadone and the PIs ritonavir and nelfinavir, although the data are less consistent. Opiate metabolism can be inhibited or induced by concomitant PIs, and patients should be monitored for signs of toxicity and/or loss of analgesia. PIs should not be coadministered with midazolam and triazolam, since prolonged sedation may occur. Interactions between agents commonly prescribed for patients with HIV and recreational drugs can occur, and may be associated with serious clinical consequences. Clinicians should encourage open dialog with their patients on this topic, to avoid compromising antiretroviral efficacy and increasing the risk of drug toxicity.

Clinically significant drug-drug interactions involving opioid analgesics used for pain treatment in patients with cancer: a systematic review.

PubMed

Kotlinska-Lemieszek, Aleksandra; Klepstad, Pål; Haugen, Dagny Faksvåg

2015-01-01

Opioids are the most frequently used drugs to treat pain in cancer patients. In some patients, however, opioids can cause adverse effects and drug-drug interactions. No advice concerning the combination of opioids and other drugs is given in the current European guidelines. To identify studies that report clinically significant drug-drug interactions involving opioids used for pain treatment in adult cancer patients. Systematic review with searches in Embase, MEDLINE, and Cochrane Central Register of Controlled Trials from the start of the databases (Embase from 1980) through January 2014. In addition, reference lists of relevant full-text papers were hand-searched. Of 901 retrieved papers, 112 were considered as potentially eligible. After full-text reading, 17 were included in the final analysis, together with 15 papers identified through hand-searching of reference lists. All of the 32 included publications were case reports or case series. Clinical manifestations of drug-drug interactions involving opioids were grouped as follows: 1) sedation and respiratory depression, 2) other central nervous system symptoms, 3) impairment of pain control and/or opioid withdrawal, and 4) other symptoms. The most common mechanisms eliciting drug-drug interactions were alteration of opioid metabolism by inhibiting the activity of cytochrome P450 3A4 and pharmacodynamic interactions due to the combined effect on opioid, dopaminergic, cholinergic, and serotonergic activity in the central nervous system. Evidence for drug-drug interactions associated with opioids used for pain treatment in cancer patients is very limited. Still, the cases identified in this systematic review give some important suggestions for clinical practice. Physicians prescribing opioids should recognize the risk of drug-drug interactions and if possible avoid polypharmacy.

42 CFR 8.33 - Written decision.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Written decision. 8.33 Section 8.33 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID... Adverse Action Regarding Withdrawal of Approval of an Accreditation Body § 8.33 Written decision. (a...

42 CFR 8.33 - Written decision.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 1 2011-10-01 2011-10-01 false Written decision. 8.33 Section 8.33 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CERTIFICATION OF OPIOID... Adverse Action Regarding Withdrawal of Approval of an Accreditation Body § 8.33 Written decision. (a...

Pharmacologic Profile of Naloxegol, a Peripherally Acting µ-Opioid Receptor Antagonist, for the Treatment of Opioid-Induced Constipation.

PubMed

Floettmann, Eike; Bui, Khanh; Sostek, Mark; Payza, Kemal; Eldon, Michael

2017-05-01

Opioid-induced constipation (OIC) is a common side effect of opioid pharmacotherapy for the management of pain because opioid agonists bind to µ -opioid receptors in the enteric nervous system (ENS). Naloxegol, a polyethylene glycol derivative of naloxol, which is a derivative of naloxone and a peripherally acting µ -opioid receptor antagonist, targets the physiologic mechanisms that cause OIC. Pharmacologic measures of opioid activity and pharmacokinetic measures of central nervous system (CNS) penetration were employed to characterize the mechanism of action of naloxegol. At the human µ -opioid receptor in vitro, naloxegol was a potent inhibitor of binding ( K i = 7.42 nM) and a neutral competitive antagonist (p A 2 - 7.95); agonist effects were <10% up to 30 μ M and identical to those of naloxone. The oral doses achieving 50% of the maximal effect in the rat for antagonism of morphine-induced inhibition of gastrointestinal transit and morphine-induced antinociception in the hot plate assay were 23.1 and 55.4 mg/kg for naloxegol and 0.69 and 1.14 mg/kg by for naloxone, respectively. In the human colon adenocarcinoma cell transport assay, naloxegol was a substrate for the P-glycoprotein transporter, with low apparent permeability in the apical to basolateral direction, and penetrated the CNS 15-fold slower than naloxone in a rat brain perfusion model. Naloxegol-derived radioactivity was poorly distributed throughout the rat CNS and was eliminated from most tissues within 24 hours. These findings corroborate phase 3 clinical studies demonstrating that naloxegol relieves OIC-associated symptoms in patients with chronic noncancer pain by antagonizing the µ -opioid receptor in the ENS while preserving CNS-mediated analgesia. Copyright © 2017 The Author(s).

Pharmacologic Profile of Naloxegol, a Peripherally Acting µ-Opioid Receptor Antagonist, for the Treatment of Opioid-Induced Constipation

PubMed Central

Floettmann, Eike; Sostek, Mark; Payza, Kemal; Eldon, Michael

2017-01-01

Opioid-induced constipation (OIC) is a common side effect of opioid pharmacotherapy for the management of pain because opioid agonists bind to µ-opioid receptors in the enteric nervous system (ENS). Naloxegol, a polyethylene glycol derivative of naloxol, which is a derivative of naloxone and a peripherally acting µ-opioid receptor antagonist, targets the physiologic mechanisms that cause OIC. Pharmacologic measures of opioid activity and pharmacokinetic measures of central nervous system (CNS) penetration were employed to characterize the mechanism of action of naloxegol. At the human µ-opioid receptor in vitro, naloxegol was a potent inhibitor of binding (Ki = 7.42 nM) and a neutral competitive antagonist (pA2 - 7.95); agonist effects were <10% up to 30 μM and identical to those of naloxone. The oral doses achieving 50% of the maximal effect in the rat for antagonism of morphine-induced inhibition of gastrointestinal transit and morphine-induced antinociception in the hot plate assay were 23.1 and 55.4 mg/kg for naloxegol and 0.69 and 1.14 mg/kg by for naloxone, respectively. In the human colon adenocarcinoma cell transport assay, naloxegol was a substrate for the P-glycoprotein transporter, with low apparent permeability in the apical to basolateral direction, and penetrated the CNS 15-fold slower than naloxone in a rat brain perfusion model. Naloxegol-derived radioactivity was poorly distributed throughout the rat CNS and was eliminated from most tissues within 24 hours. These findings corroborate phase 3 clinical studies demonstrating that naloxegol relieves OIC-associated symptoms in patients with chronic noncancer pain by antagonizing the µ-opioid receptor in the ENS while preserving CNS-mediated analgesia. PMID:28336575

Gender issues in the pharmacotherapy of opioid-addicted women: buprenorphine.

PubMed

Unger, Annemarie; Jung, Erika; Winklbaur, Bernadette; Fischer, Gabriele

2010-04-01

Gender, a biological determinant of mental health and illness, plays a critical role in determining patients' susceptibility, exposure to mental health risks, and related outcomes. Regarding sex differences in the epidemiology of opioid dependence, one third of the patients are women of childbearing age. Women have an earlier age of initiation of substance use and a more rapid progression to drug involvement and dependence than men. Generally few studies exist which focus on the special needs of women in opioid maintenance therapy. The aim of this paper is to provide an overview of treatment options for opioid-dependent women, with a special focus on buprenorphine, and to look at recent findings related to other factors that should be taken into consideration in optimizing the treatment of opioid-dependent women. Issues addressed include the role of gender in the choice of medication assisted treatment, sex differences in pharmacodynamics and pharmacokinetics of buprenorphine drug interactions, cardiac interactions, induction of buprenorphine in pregnant patients, the neonatal abstinence syndrome and breastfeeding. This paper aims to heighten the awareness for the need to take gender into consideration when making treatment decisions in an effort to optimize services and enhance the quality of life of women suffering from substance abuse.

Comparative pharmacokinetics of intravenous fentanyl and buprenorphine in healthy Greyhound dogs

PubMed Central

KuKanich, Butch; Allen, Philip

2014-01-01

The purpose of this study was to compare the pharmacokinetics of two highly protein bound, lipophilic opioid drugs. Fentanyl (10 μg/kg) and buprenorphine (20 μg/kg) were administered intravenously (IV) to six healthy Greyhound dogs (3 males and 3 females). The doses were based on clinically administered doses for dogs. Plasma drug concentrations were determined using liquid chromatography with mass spectrometry and noncompartmental pharmacokinetics were estimated with computer software. The volume of distribution (area) was larger for fentanyl (7.42 L/kg) compared to buprenorphine (3.54 L/kg). The plasma clearance of fentanyl (38.6 mL/min/kg) was faster than buprenorphine (10.3 mL/min/kg). The terminal half-life of fentanyl (2.22 h) was shorter than buprenorphine (3.96 h). Despite similar physicochemical properties including: octanol:water partition coefficient and pKa the pharmacokinetics of fentanyl and buprenorphine were not similar. Both fentanyl (84%) and buprenorphine (95-98%) are considered highly protein bound, but the differences in protein binding may contribute to the lack of similarity of pharmacokinetics in healthy dogs. PMID:24684621

Buprenorphine-naloxone buccal soluble film for the treatment of opioid dependence: current update.

PubMed

Soyka, Michael

2015-02-01

Opioid dependence is a severe medical disorder with a high psychiatric and somatic comorbidity and mortality rate. The opioid agonist methadone, mixed agonist-antagonist buprenorphine and the combination of buprenorphine with the opioid antagonist naloxone are the first-line maintenance treatments for opioid dependence. Risk of diversion and accidental intoxications, especially in children, are of great concern. To lower these risks, a novel buprenorphine-naloxone film has been developed and introduced in the USA and Australia. This review evaluates the available preclinical and clinical data on the novel buprenorphine-naloxone film for treatment of opioid dependence. Literature was identified through a comprehensive PubMed search. Data sources also included official FDA information and material made public by the manufacturer. Few preclinical and clinical data on safety and efficacy have been published. The pharmacological differences between the novel film and the conventional buprenorphine/naloxone are small. In an experimental study, the new formulation suppressed symptoms of opioid withdrawal. The spectrum of adverse events seems to be similar to that of the conventional sublingual tablet. Recent data show that patients prefer the novel film over the conventional sublingual tablet. Emerging surveillance data indicate a lower risk of accidental poisoning in children compared with the conventional formulation. Further clinical and preclinical data are needed to explore additional possible advantages of the new formulation.

Social environment alters opioid-induced hyperalgesia and antinociceptive tolerance in adolescent mice.

PubMed

Bates, M L S; Emery, M A; Wellman, P J; Eitan, S

2016-07-01

Chronic opioid treatment is complicated by the development of tolerance and hyperalgesia. Social environment alters both opioid-induced behaviours and nociceptive mechanisms. Our previous studies demonstrated that, in adolescent rodents, the susceptibility to acquire opioid dependence and reward is dependent on the nature of social housing conditions. Specifically, our previous studies demonstrate that housing morphine-treated mice with drug-naïve animals mitigates the abuse liability of opioids. Thus, this study tested the effect of social housing conditions on the development of adaptive processes to morphine antinociception. Adolescent males were group-housed in different conditions. In the mixed treatment condition, mice treated with 20 mg/kg morphine (i.e. 'morphine cage-mates') and saline (i.e. 'saline cage-mates') were housed together. In the separated treatment conditions, all mice in the cage received morphine (i.e. 'morphine only') or saline (i.e. 'saline only'). All animals were tested for baseline pain sensitivity and for the response to morphine in the tail withdrawal, hot plate, acetone and von Frey filament tests, during and after discontinuation of opioid treatment. Both morphine cage-mate and morphine only animals developed antinociceptive tolerance. However, this effect was more robust and persistent in the morphine only group. Notably, morphine only animals, but not morphine cage-mates, developed opioid-induced hyperalgesia. This study demonstrates that housing morphine-treated mice with drug-naïve animals mitigates the development of opioid-induced hyperalgesia and antinociceptive tolerance. Thus, this study indicates that social environment influences the effectiveness of opioid pain management. © 2016 European Pain Federation - EFIC®

Postoperative analgesia after pulmonary resection with a focus on video-assisted thoracoscopic surgery.

PubMed

Umari, Marzia; Carpanese, Valentina; Moro, Valeria; Baldo, Gaia; Addesa, Stefano; Lena, Enrico; Lovadina, Stefano; Lucangelo, Umberto

2018-05-01

Video-assisted thoracoscopic surgery is a widespread technique that has been linked to improved postoperative respiratory function, reduced hospital length of stay and a higher level of tolerability for the patients. Acute postoperative pain is of considerable significance, and the late development of neuropathic pain syndrome is also an issue. As anaesthesiologists, we have investigated the available evidence to optimize postoperative pain management. An opioid-sparing multimodal approach is highly recommended. Loco-regional techniques such as the thoracic epidural and peripheral blocks can be performed. Several adjuvants have been employed with varying degrees of success both intravenously and in combination with local anesthetics. Opioids with different pharmacodynamic and pharmacokinetic profiles can be used, either through continuous infusion or on demand. Non-opioid analgesics are also beneficial. Finally, perioperative gabapentinoids may be implemented to prevent the onset of chronic neuropathic pain.

Single-dose evaluation of safety, tolerability and pharmacokinetics of newly formulated hydromorphone immediate-release and hydrophilic matrix extended-release tablets in healthy Japanese subjects without co-administration of an opioid antagonist.

PubMed

Toyama, Kaoru; Uchida, Naoki; Ishizuka, Hitoshi; Sambe, Takehiko; Kobayashi, Shinichi

2015-09-01

This single dose, open-label study investigated the safety, tolerability and pharmacokinetics of single oral doses of newly formulated immediate-release (IR) and hydrophilic matrix extended-release (ER) hydromorphone tablets in healthy Japanese subjects without co-administration of an opioid antagonist under fasting and fed conditions. Plasma and urinary concentrations of hydromorphone and metabolites were measured by liquid-chromatography tandem mass-spectroscopy. Following administration of the ER tablet, plasma concentrations of hydromorphone slowly increased with a median tmax of 5.0 h and the Cmax decreased to 37% of the IR tablet, while the AUC0-inf was comparable with that of the IR tablet when administered at the same dose. The degree of fluctuation in the plasma concentration for the ER tablet was much lower than that of the IR tablet and certain levels of plasma concentrations were maintained after 24 h of ER dosing. The AUC0-inf and Cmax increased with food for both IR and ER tablets. The AUC0-inf of hydromorphone-3-glucoside was one-tenth of that of hydromorphone-3-glucuronide. A single oral administration of the hydromorphone tablets would be well-tolerated in healthy Japanese subjects despite a lack of co-administration of an opioid antagonist and the newly developed ER hydromorphone tablets may have the appropriate PK characteristics for once-daily dosing. © 2015, The American College of Clinical Pharmacology.

Objective methods for the assessment of the spinal and supraspinal effects of opioids.

PubMed

Fischer, Iben W; Hansen, Tine M; Lelic, Dina; Brokjaer, Anne; Frøkjær, Jens; Christrup, Lona L; Olesen, Anne E

2017-01-01

Opioids are potent analgesics. Opioids exert effects after interaction with opioid receptors. Opioid receptors are present in the peripheral- and central nervous system (CNS), but the analgesic effects are primarily mediated via receptors in the CNS. Objective methods for assessment of opioid effects may increase knowledge on the CNS processes responsible for analgesia. The aim of this review was to provide an overview of the most common objective methods for assessment of the spinal and supraspinal effects of opioids and discuss their advantages and limitations. The literature search was conducted in Pub Med (http://www.ncbi.nlm.nih.gov/pubmed) from November 2014 to June 2016, using free-text terms: "opioid", "morphine" and "oxycodone" combined with the terms "pupillometry," "magnetic resonance spectroscopy," "fMRI," "BOLD," "PET," "pharmaco-EEG", "electroencephalogram", "EEG," "evoked potentials," and "nociceptive reflex". Only original articles published in English were included. For assessment of opioid effects at the supraspinal level, the following methods are evaluated: pupillometry, proton magnetic resonance spectroscopy, functional resonance magnetic imaging (fMRI), positron emission tomography (PET), spontaneous electroencephalogram (EEG) and evoked potentials (EPs). Pupillometry is a non-invasive tool used in research as well as in the clinical setting. Proton magnetic resonance spectroscopy has been used for the last decades and it is a non-invasive technique for measurement of in vivo brain metabolite concentrations. fMRI has been a widely used non-invasive method to estimate brain activity, where typically from the blood oxygen level-dependent (BOLD) signal. PET is a nuclear imaging technique based on tracing radio labeled molecules injected into the blood, where receptor distribution, density and activity in the brain can be visualized. Spontaneous EEG is typically quantified in frequency bands, power spectrum and spectral edge frequency. EPs are brain responses (assessed by EEG) to a predefined number of short phasic stimuli. EPs are quantified by their peak latencies and amplitudes, power spectrum, scalp topographies and brain source localization. For assessment of opioid effects at the spinal level, the following methods are evaluated: the nociceptive withdrawal reflex (NWR) and spinal EPs. The nociceptive withdrawal reflex can be recorded from all limbs, but it is standard to record the electromyography signal at the biceps femoris muscle after stimulation of the ipsilateral sural nerve; EPs can be recorded from the spinal cord and are typically recorded after stimulation of the median nerve at the wrist. The presented methods can all be used as objective methods for assessing the centrally mediated effects of opioids. Advantages and limitations should be considered before implementation in drug development, future experimental studies as well as in clinical settings. In conclusion, pupillometry is a sensitive measurement of opioid receptor activation in the CNS and from a practical and economical perspective it may be used as a biomarker for opioid effects in the CNS. However, if more detailed information is needed on opioid effects at different levels of the CNS, then EEG, fMRI, PET and NWR have the potential to be used. Finally, it is conceivable that information from different methods should be considered together for complementary information. Copyright © 2016 Scandinavian Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Combined Interactions with I1-, I2-Imidazoline Binding Sites and α2-Adrenoceptors To Manage Opioid Addiction

PubMed Central

2016-01-01

Tolerance and dependence associated with chronic opioid exposure result from molecular, cellular, and neural network adaptations. Such adaptations concern opioid and nonopioid systems, including α2-adrenoceptors (α2-ARs) and I1- and I2-imidazoline binding sites (IBS). Agmatine, one of the hypothesized endogenous ligands of IBS, targeting several systems including α2-ARs and IBS, proved to be able to regulate opioid-induced analgesia and to attenuate the development of tolerance and dependence. Interested in the complex pharmacological profile of agmatine and considering the nature of its targets, we evaluated two series of imidazolines, rationally designed to simultaneously interact with I1-/I2-IBS or I1-/I2-IBS/α2-ARs. The compounds showing the highest affinities for I1-/I2-IBS or I1-/I2-IBS/α2-ARs have been selected for their in vivo evaluation on opiate withdrawal syndrome. Interestingly, 9, displaying I1-/I2-IBS/α2-ARs interaction profile, appears more effective in reducing expression and acquisition of morphine dependence and, therefore, might be considered a promising tool in managing opioid addiction. PMID:27774136

[Treatment of pain with peridural administration of opioids].

PubMed

Chrubasik, S; Senninger, N; Chrubasik, J

1996-07-01

The advantages and disadvantages associated with epidural opioids require careful selection of the opioid and its dosage. There is presently no ideal opioid available for epidural use. Comparative pharmacokinetic data help to select the appropriate epidural opioid. Morphine (provided it is given in small doses and volumes) is very appropriate for epidural pain treatment, especially for longer periods of treatment, due to excellent analgesia and very low systemic morphine concentrations. The faster onset of analgesia with epidural pethidine, alfentanil und fentanyl make these opioids recommendable. However, due to the increased risk of respiratory depression during continuous treatment, these drugs should not be given over extended periods. Epidural administration of methadone, sufentanil und buprenorphine cannot be recommended since the advantages over systemic use do not outweigh the risks. Epidural tramadol may be useful in clinical routine, if opioids are not available and supervision of the patient is not guaranteed, because tramadol is not restricted by law and has a low potential for central depressive effects. The safety of the patients should be paramount. If patients are harmed by inappropriate opioids or dose regimens this will discredit a valuable for treating postoperative pain. Postoperative epidural dosages should be as low as possible and be titrated to the patient's individual needs for analgesia. Epidural morphine treatment is an alternative to step 4 of the WHO treatment regimen for patients with intractable pain or those suffering from systemic opioid side effects. Careful selection of patients helps to increase successful treatment. If implantable devices (ports or pumps, according to the life expectancy) are employed, the intrathecal route of administration is preferable to the epidural route, as the latter has a 10 times higher morphine dose requirement.

A review of factors explaining variability in fentanyl pharmacokinetics; focus on implications for cancer patients

PubMed Central

Zandvliet, Maarten L.; Koolen, Stijn L. W.; Mathijssen, Ron H. J.; van der Rijt, Carin C. D.

2016-01-01

Fentanyl is a strong opioid that is available for various administration routes, and which is widely used to treat cancer‐related pain. Many factors influence the fentanyl pharmacokinetics leading to a wide inter‐ and intrapatient variability. This systematic review summarizes multiple studied factors that potentially influence fentanyl pharmacokinetics with a focus on implications for cancer patients. The use of CYP3A4 inhibitors and inducers, impaired liver function, and heating of the patch potentially influence fentanyl pharmacokinetics in a clinically relevant way. In elderly patients, current data suggest that we should carefully dose fentanyl due to alterations in absorption and metabolism. The influence of BMI and gender on fentanyl pharmacokinetics is questionable, most probably due to a large heterogeneity in the published studies. Pharmacogenetics, e.g. the CYP3A5*3 gene polymorphism, may influence fentanyl pharmacokinetics as well, although further study is warranted. Several other factors have been studied but did not show significant and clinically relevant effects on fentanyl pharmacokinetics. Unfortunately, most of the published papers that studied factors influencing fentanyl pharmacokinetics describe healthy volunteers instead of cancer patients. Results from the studies in volunteers may not be simply extrapolated to cancer patients because of multiple confounding factors. To handle fentanyl treatment in a population of cancer patients, it is essential that physicians recognize factors that influence fentanyl pharmacokinetics, thereby preventing potential side‐effects and increasing its efficacy. PMID:27619152

Opioid transport by ATP-binding cassette transporters at the blood-brain barrier: implications for neuropsychopharmacology.

PubMed

Tournier, Nicolas; Declèves, Xavier; Saubaméa, Bruno; Scherrmann, Jean-Michel; Cisternino, Salvatore

2011-01-01

Some of the ATP-binding cassette (ABC) transporters like P-glycoprotein (P-gp; ABCB1, MDR1), BCRP (ABCG2) and MRPs (ABCCs) that are present at the blood-brain barrier (BBB) influence the brain pharmacokinetics (PK) of their substrates by restricting their uptake or enhancing their clearance from the brain into the blood, which has consequences for their CNS pharmacodynamics (PD). Opioid drugs have been invaluable tools for understanding the PK-PD relationships of these ABC-transporters. The effects of morphine, methadone and loperamide on the CNS are modulated by P-gp. This review examines the ways in which other opioid drugs and some of their active metabolites interact with ABC transporters and suggests new mechanisms that may be involved in the variability of the response of the CNS to these drugs like carrier-mediated system belonging to the solute carrier (SLC) superfamily. Exposure to opioids may also alter the expression of ABC transporters. P-gp can be overproduced during morphine treatment, suggesting that the drug has a direct or, more likely, an indirect action. Variations in cerebral neurotransmitters during exposure to opioids and the release of cytokines during pain could be new endogenous stimuli affecting transporter synthesis. This review concludes with an analysis of the pharmacotherapeutic and clinical impacts of the interactions between ABC transporters and opioids.

Oral opioid administration and hyperalgesia in patients with cancer or chronic nonmalignant pain.

PubMed

Reznikov, Igor; Pud, Dorit; Eisenberg, Elon

2005-09-01

Previous research has reported on reduced paw withdrawal latencies to heat and mechanical stimuli after parenteral administration of opioids in animals and on increased pain sensitivity in humans subsequent to postoperative infusions of short-acting opioids or in drug addicts. The aim of the present study was to explore the possibility that oral opioid treated patients with cancer-related or chronic nonmalignant pain differ in their pain sensitivity from patients treated with non-opioid analgesics. The study population consisted of 224 patients, including 142 in the opioid-treated group and 82 in the non-opioid-treated group. Pain thresholds for punctuate measured by von Frey filaments (g), mechanical pressure measured by pressure algometer (mmHg), heat stimuli measured by quantitative sensory testing (degrees C), as well as suprathreshold tonic heat pain intensity (46.5 degrees C for 1 min) measured by 0-10 numerical pain scale (NPS) were obtained at a nonpainful site (thenar eminence) in all patients. No differences between the groups were found for gender, age, duration of pain, or duration of treatment (independent variables). No significant differences between the groups were found in punctuate (difference = 17.0 g (95% CI -8.8, 42.8), P = 0.19), pressure (2.2 mmHg (-28.7, 33.2), P = 0.89) and heat (-0.3 degrees C (-1.5, 0.9), P = 0.70) pain thresholds, or in suprathreshold heat pain intensity (difference between maximal pain intensities -0.4 NPS units (95% CI -1.2, 0.4), P = 0.31). Pearson correlations within the opioid-treated group failed to show significant relationships between any of the independent variables and the outcome measures. A further comparison of the outcomes between the 'weak' opioid-treated subgroup and the 'strong' opioid-treated subgroup again revealed insignificant results. These results suggest that the administration of 'commonly used' dosages of oral opioids does not result in abnormal pain sensitivity beyond that of patients receiving non-opioid analgesia.

Emerging therapies for patients with symptoms of opioid-induced bowel dysfunction

PubMed Central

Leppert, Wojciech

2015-01-01

Opioid-induced bowel dysfunction (OIBD) comprises gastrointestinal (GI) symptoms, including dry mouth, nausea, vomiting, gastric stasis, bloating, abdominal pain, and opioid-induced constipation, which significantly impair patients’ quality of life and may lead to undertreatment of pain. Traditional laxatives are often prescribed for OIBD symptoms, although they display limited efficacy and exert adverse effects. Other strategies include prokinetics and change of opioids or their administration route. However, these approaches do not address underlying causes of OIBD associated with opioid effects on mostly peripheral opioid receptors located in the GI tract. Targeted management of OIBD comprises purely peripherally acting opioid receptor antagonists and a combination of opioid receptor agonist and antagonist. Methylnaltrexone induces laxation in 50%–60% of patients with advanced diseases and OIBD who do not respond to traditional oral laxatives without inducing opioid withdrawal symptoms with similar response (45%–50%) after an oral administration of naloxegol. A combination of prolonged-release oxycodone with prolonged-release naloxone (OXN) in one tablet (a ratio of 2:1) provides analgesia with limited negative effect on the bowel function, as oxycodone displays high oral bioavailability and naloxone demonstrates local antagonist effect on opioid receptors in the GI tract and is totally inactivated in the liver. OXN in daily doses of up to 80 mg/40 mg provides equally effective analgesia with improved bowel function compared to oxycodone administered alone in patients with chronic non-malignant and cancer-related pain. OIBD is a common complication of long-term opioid therapy and may lead to quality of life deterioration and undertreatment of pain. Thus, a complex assessment and management that addresses underlying causes and patomechanisms of OIBD is recommended. Newer strategies comprise methylnaltrexone or OXN administration in the management of OIBD, and OXN may be also considered as a preventive measure of OIBD development in patients who require opioid administration. PMID:25931815

Elevated mu-opioid receptor expression in the nucleus of the solitary tract accompanies attenuated withdrawal signs after chronic low dose naltrexone in opiate-dependent rats.

PubMed

Van Bockstaele, E J; Rudoy, C; Mannelli, P; Oropeza, V; Qian, Y

2006-02-15

We previously described a decrease in withdrawal behaviors in opiate-dependent rats that were chronically treated with very low doses of naltrexone in their drinking water. Attenuated expression of withdrawal behaviors correlated with decreased c-Fos expression and intracellular signal transduction elements [protein kinase A regulatory subunit II (PKA) and phosphorylated cAMP response element binding protein (pCREB)] in brainstem noradrenergic nuclei. In this study, to determine whether similar cellular changes occurred in forebrain nuclei associated with drug reward, expressions of PKA and pCREB were analyzed in the ventral tegmental area, frontal cortex, striatum, and amygdala of opiate-treated rats that received low doses of naltrexone in their drinking water. No significant difference in PKA or pCREB was detected in these regions following drug treatment. To examine further the cellular mechanisms in noradrenergic nuclei that could underlie attenuated withdrawal behaviors following low dose naltrexone administration, the nucleus of the solitary tract (NTS) and locus coeruleus (LC) were examined for opioid receptor (OR) protein expression. Results showed a significant increase in muOR expression in the NTS of morphine-dependent rats that received low doses of naltrexone in their drinking water, and increases in muOR expression were also found to be dose dependent. Protein expression of muOR in the LC and deltaOR in either brain region remained unchanged. In conclusion, our previously reported decreases in c-Fos and PKA expression in the NTS following pretreatment with low doses of naltrexone may be partially explained by a greater inhibition of NTS neurons resulting from increased muOR expression in this region.

The `One-Two Punch' of Alcoholism: Role of Central Amygdala Dynorphins / Kappa-Opioid Receptors

PubMed Central

Kissler, Jessica L.; Sirohi, Sunil; Reis, Daniel J.; Jansen, Heiko T.; Quock, Raymond M.; Smith, Daniel G.; Walker, Brendan M.

2013-01-01

Background The dynorphin (DYN)/κ-opioid receptor (KOR) system undergoes neuroadaptations following chronic alcohol exposure that promote excessive operant self-administration and negative affective-like states; however, the exact mechanisms are unknown. The present studies tested the hypothesis that an upregulated DYN/KOR system mediates excessive alcohol self-administration that occurs during withdrawal in alcohol-dependent rats by assessing DYN A peptide expression and KOR function, in combination with site-specific pharmacological manipulations. Methods Male Wistar rats were trained to self-administer alcohol using operant behavioral strategies and subjected to intermittent alcohol vapor- or air-exposure. Changes in self-administration were assessed by pharmacological challenges during acute withdrawal. In addition, 22-kHz ultrasonic vocalizations were utilized to measure negative affective-like states. Immunohistochemical techniques assessed DYN A peptide expression and [35S]GTPγS coupling assays were performed to assess KOR function. Results Alcohol-dependent rats displayed increased alcohol self-administration, negative affective-like behavior, DYN A-like immunoreactivity and KOR signaling in the amygdala compared to non-dependent controls. Site-specific infusions of a KOR antagonist selectively attenuated self-administration in dependent rats whereas, a MOR/DOR antagonist cocktail selectively reduced self-administration in non-dependent rats. A MOR antagonist/partial KOR agonist attenuated self-administration in both cohorts. Conclusion Increased DYN A and increased KOR signaling could set the stage for a `one-two punch' during withdrawal that drives excessive alcohol consumption in alcohol-dependence. Importantly, intra-CeA pharmacological challenges functionally confirmed a DYN/KOR system involvement in the escalated alcohol self-administration. Together, the DYN/KOR system is heavily dysregulated in alcohol dependence and contributes to the excessive alcohol consumption during withdrawal. PMID:23611261

Addiction is a Reward Deficit and Stress Surfeit Disorder

PubMed Central

Koob, George F.

2013-01-01

Drug addiction can be defined by a three-stage cycle – binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation – that involves allostatic changes in the brain reward and stress systems. Two primary sources of reinforcement, positive and negative reinforcement, have been hypothesized to play a role in this allostatic process. The negative emotional state that drives negative reinforcement is hypothesized to derive from dysregulation of key neurochemical elements involved in the brain reward and stress systems. Specific neurochemical elements in these structures include not only decreases in reward system function (within-system opponent processes) but also recruitment of the brain stress systems mediated by corticotropin-releasing factor (CRF) and dynorphin-κ opioid systems in the ventral striatum, extended amygdala, and frontal cortex (both between-system opponent processes). CRF antagonists block anxiety-like responses associated with withdrawal, block increases in reward thresholds produced by withdrawal from drugs of abuse, and block compulsive-like drug taking during extended access. Excessive drug taking also engages the activation of CRF in the medial prefrontal cortex, paralleled by deficits in executive function that may facilitate the transition to compulsive-like responding. Neuropeptide Y, a powerful anti-stress neurotransmitter, has a profile of action on compulsive-like responding for ethanol similar to a CRF1 antagonist. Blockade of the κ opioid system can also block dysphoric-like effects associated with withdrawal from drugs of abuse and block the development of compulsive-like responding during extended access to drugs of abuse, suggesting another powerful brain stress system that contributes to compulsive drug seeking. The loss of reward function and recruitment of brain systems provide a powerful neurochemical basis that drives the compulsivity of addiction. PMID:23914176

Tolerance to Non-Opioid Analgesics is Opioid Sensitive in the Nucleus Raphe Magnus.

PubMed

Tsagareli, Merab G; Nozadze, Ivliane; Tsiklauri, Nana; Gurtskaia, Gulnaz

2011-01-01

Repeated injection of opioid analgesics can lead to a progressive loss of effect. This phenomenon is known as tolerance. Several lines of investigations have shown that systemic, intraperitoneal administration or the microinjection of non-opioid analgesics, non-steroidal anti-inflammatory drugs (NSAIDs) into the midbrain periaqueductal gray matter induces antinociception with some effects of tolerance. Our recent study has revealed that microinjection of three drugs analgin, ketorolac, and xefocam into the central nucleus of amygdala produce tolerance to them and cross-tolerance to morphine. Here we report that repeated administrations of these NSAIDs into the nucleus raphe magnus (NRM) in the following 4 days result in progressively less antinociception compare to the saline control, i.e., tolerance develops to these drugs in male rats. Special control experiments showed that post-treatment with the μ-opioid antagonist naloxone into the NRM significantly decreased antinociceptive effects of NSAIDs on the first day of testing in the tail-flick (TF) reflex and hot plate (HP) latency tests. On the second day, naloxone generally had trend effects in both TF and HP tests and impeded the development of tolerance to the antinociceptive effect of non-opioid analgesics. These findings strongly support the suggestion of endogenous opioid involvement in NSAIDs antinociception and tolerance in the descending pain-control system. Moreover, repeated injections of NSAIDs progressively lead to tolerance to them, cross-tolerance to morphine, and the risk of a withdrawal syndrome. Therefore, these results are important for human medicine too.

Stress-induced analgesia and morphine responses are changed in catechol-O-methyltransferase-deficient male mice.

PubMed

Kambur, Oleg; Männistö, Pekka T; Viljakka, Kaarin; Reenilä, Ilkka; Lemberg, Kim; Kontinen, Vesa K; Karayiorgou, Maria; Gogos, Joseph A; Kalso, Eija

2008-10-01

Catechol-O-methyltransferase (COMT) polymorphisms modulate pain and opioid analgesia in human beings. It is not clear how the effects of COMT are mediated and only few relevant animal studies have been performed. Here, we used old male Comt gene knock-out mice as an animal model to study the effects of COMT deficiency on nociception that was assessed by the hot plate and tail flick tests. Stress-induced analgesia was achieved by forced swim. Morphine antinociception was measured after 10 mg/kg of morphine subcutaneously. Morphine tolerance was produced with subcutaneous morphine pellets and withdrawal provoked with subcutaneous naloxone. In the hot plate test, morphine-induced antinociception was significantly greater in the COMT knock-out mice, compared to the wild-type mice. This may be due to increased availability of opioid receptors as suggested by previous human studies. In the tail flick test, opioid-mediated stress-induced analgesia was absent and morphine-induced analgesia was decreased in COMT knock-out mice. In the hot plate test, stress-induced analgesia developed to all mice regardless of the COMT genotype. There were no differences between the genotypes in the baseline nociceptive thresholds, morphine tolerance and withdrawal. Our findings show, for the first time, the importance of COMT activity in stress- and morphine-induced analgesia in mice. COMT activity seems to take part in the modulation of nociception not only in the brain, as suggested earlier, but also at the spinal/peripheral level.

Characterisation of tramadol, morphine and tapentadol in an acute pain model in Beagle dogs.

PubMed

Kögel, Babette; Terlinden, Rolf; Schneider, Johannes

2014-05-01

To evaluate the analgesic potential of the centrally acting analgesics tramadol, morphine and the novel analgesic tapentadol in a pre-clinical research model of acute nociceptive pain, the tail-flick model in dogs. Prospective part-randomized pre-clinical research trial. Fifteen male Beagle dogs (HsdCpb:DOBE), aged 12-15 months. On different occasions separated by at least 1 week, dogs received intravenous (IV) administrations of tramadol (6.81, 10.0 mg kg(-1) ), tapentadol (2.15, 4.64, 6.81 mg kg(-1) ) or morphine (0.464, 0.681, 1.0 mg kg(-1) ) with subsequent measurement of tail withdrawal latencies from a thermal stimulus (for each treatment n = 5). Blood samples were collected immediately after the pharmacodynamic measurements of tramadol to determine pharmacokinetics and the active metabolite O-demethyltramadol (M1). Tapentadol and morphine induced dose-dependent antinociception with ED50-values of 4.3 mg kg(-1) and 0.71 mg kg(-1) , respectively. In contrast, tramadol did not induce antinociception at any dose tested. Measurements of the serum levels of tramadol and the M1 metabolite revealed only marginal amounts of the M1 metabolite, which explains the absence of the antinociceptive effect of tramadol in this experimental pain model in dogs. Different breeds of dogs might not or only poorly respond to treatment with tramadol due to low metabolism of the drug. Tapentadol and morphine which act directly on μ-opioid receptors without the need for metabolic activation are demonstrated to induce potent antinociception in the experimental model used and should also provide a reliable pain management in the clinical situation. The non-opioid mechanisms of tramadol do not provide antinociception in this experimental setting. This contrasts to many clinical situations described in the literature, where tramadol appears to provide useful analgesia in dogs for post-operative pain relief and in more chronically pain states. © 2014 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

Traditional Chinese and Indian medicine in the treatment of opioid-dependence: a review.

PubMed

Doosti, Fatemeh; Dashti, Saeedeh; Tabatabai, Seyed Meghdad; Hosseinzadeh, Hossein

2013-01-01

In this study, the current literatures on the use of herbs and herbal preparations of Traditional Chinese and Indian Medicine for the treatment of opioid addiction were reviewed. Matherials and Methods: Search was done in databases such as Pub Med, Science Direct, Scopus, Springer Link, and Google Scholar. Among 18 retrieved studies, 3 studies were about asafetida extract, an approved preparation for ameliorating drug abstinence in China. Chinese preparations including Composite Dong Yuan Gao, Qingjunyin and TJ-97 (a water extract of dai-bofu-to) as well as Indian ones, Mentate and Shilajit, were reported to have positive effects against opioid withdrawal, dependence, and tolerance. Moreover, Levo-tetrahydropalmatine and L-Stepholidine, in addition to extracts of Caulis Sinomenii and Sinomenium acutum showed similar effects. Banxia Houpu Decoction, Fu-Yuan pellet, Jinniu capsules, Qingjunyin, Tai-Kang-Ning capsule, and Xuan Xia Qudu Jiaonang (WeiniCom) from Chinese preparations, showed anti-addiction effects in randomized, double-blind and, in some studies, multicenter clinical trials. Conclusion : Traditional herbal preparations of China and India have anti-addiction effects with less adverse effects than alpha2-adrenergic or opioid agonists.

Nicotine anxiogenic and rewarding effects are decreased in mice lacking β-endorphin

PubMed Central

Trigo, José M.; Zimmer, Andreas; Maldonado, Rafael

2009-01-01

The endogenous opioid system plays an important role in the behavioral effects of nicotine. Thus, μ-opioid receptor and the endogenous opioids derived from proenkephalin are involved in the central effects of nicotine. However, the role played by the different endogenous opioid peptides in the acute and chronic effects of nicotine remains to be fully established. Mice lacking β-endorphin were acutely injected with nicotine at different doses to evaluate locomotor, anxiogenic and antinociceptive responses. The rewarding properties of nicotine were evaluated by using the conditioned place-preference paradigm. Mice chronically treated with nicotine were acutely injected with mecamylamine to study the behavioral expression of nicotine withdrawal. Mice lacking β-endorphin exhibited a spontaneous hypoalgesia and hyperlocomotion and a reduction on the anxiogenic and rewarding effects induced by nicotine. Nicotine induced similar antinociception and hypolocomotion in both genotypes and no differences were found in the development of physical dependence. The dissociation between nicotine rewarding properties and physical dependence suggests a differential implication of β-endorphin in these addictive related responses. PMID:19376143

Management of neonatal abstinence syndrome in neonates born to opioid maintained women.

PubMed

Ebner, Nina; Rohrmeister, Klaudia; Winklbaur, Bernadette; Baewert, Andjela; Jagsch, Reinhold; Peternell, Alexandra; Thau, Kenneth; Fischer, Gabriele

2007-03-16

Neonates born to opioid-maintained mothers are at risk of developing neonatal abstinence syndrome (NAS), which often requires pharmacological treatment. This study examined the effect of opioid maintenance treatment on the incidence and timing of NAS, and compared two different NAS treatments (phenobarbital versus morphine hydrochloride). Fifty-three neonates born to opioid-maintained mothers were included in this study. The mothers received methadone (n=22), slow-release oral morphine (n=17) or buprenorphine (n=14) throughout pregnancy. Irrespective of maintenance treatment, all neonates showed APGAR scores comparable to infants of non-opioid dependent mothers. No difference was found between the three maintenance groups regarding neonatal weight, length or head circumference. Sixty percent (n=32) of neonates required treatment for NAS [68% in the methadone-maintained group (n=15), 82% in the morphine-maintained group (n=14), and 21% in the buprenorphine-maintained group (n=3)]. The mean duration from birth to requirement of NAS treatment was 33 h for the morphine-maintained group, 34 h for the buprenorphine-maintained group and 58 h for the methadone-maintained group. In neonates requiring NAS treatment, those receiving morphine required a significantly shorter mean duration of treatment (9.9 days) versus those treated with phenobarbital (17.7 days). Results suggest that morphine hydrochloride is preferable for neonates suffering NAS due to opioid withdrawal.

Differential effects of left and right neuropathy on opioid gene expression in lumbar spinal cord.

PubMed

Kononenko, Olga; Mityakina, Irina; Galatenko, Vladimir; Watanabe, Hiroyuki; Bazov, Igor; Gerashchenko, Anna; Sarkisyan, Daniil; Iatsyshyna, Anna; Yakovleva, Tatiana; Tonevitsky, Alex; Marklund, Niklas; Ossipov, Michael H; Bakalkin, Georgy

2018-05-28

The endogenous opioid system (EOS) controls the processing of nociceptive stimuli and is a pharmacological target for opioids. Alterations in expression of the EOS genes under neuropathic pain condition may account for low efficacy of opioid drugs. We here examined whether EOS expression patterns are altered in the lumbar spinal cord of the rats with spinal nerve ligation (SNL) as a neuropathic pain model. Effects of the left- and right-side SNL on expression of EOS genes in the ipsi- and contralateral spinal domains were analysed. The SNL-induced changes were complex and different between the genes; between the dorsal and ventral spinal domains; and between the left and right sides of the spinal cord. Prodynorphin (Pdyn) expression was upregulated in the ipsilateral dorsal domains by each the left and right-side SNL, while changes in expression of μ-opioid receptor (Oprm1) and proenkephalin (Penk) genes were dependent on the SNL side. Changes in expression of the Pdyn and κ-opioid receptor (Oprk1) genes were coordinated between the ipsi- and contralateral sides. Withdrawal response thresholds, indicators of mechanical allodynia correlated negatively with Pdyn expression in the right ventral domain after right side SNL. These findings suggest multiple roles of the EOS gene products in spinal sensitization and changes in motor reflexes, which may differ between the left and right sides. Copyright © 2018. Published by Elsevier B.V.

Low doses of cyclic AMP-phosphodiesterase inhibitors rapidly evoke opioid receptor-mediated thermal hyperalgesia in naïve mice which is converted to prominent analgesia by cotreatment with ultra-low-dose naltrexone.

PubMed

Crain, Stanley M; Shen, Ke-Fei

2008-09-22

Systemic (s.c.) injection in naïve mice of cyclic AMP-phosphodiesterase (cAMP-PDE) inhibitors, e.g. 3-isobutyl-1-methylxanthine [(IBMX) or caffeine, 10 mg/kg] or the more specific cAMP-PDE inhibitor, rolipram (1 mug/kg), rapidly evokes thermal hyperalgesia (lasting >5 h). These effects appear to be mediated by enhanced excitatory opioid receptor signaling, as occurs during withdrawal in opioid-dependent mice. Cotreatment of these mice with ultra-low-dose naltrexone (NTX, 0.1 ng/kg-1 pg/kg, s.c.) results in prominent opioid analgesia (lasting >4 h) even when the dose of rolipram is reduced to 1 pg/kg. Cotreatment of these cAMP-PDE inhibitors in naïve mice with an ultra-low-dose (0.1 ng/kg) of the kappa-opioid receptor antagonist, nor-binaltorphimine (nor-BNI) or the mu-opioid receptor antagonist, beta-funaltrexamine (beta-FNA) also results in opioid analgesia. These excitatory effects of cAMP-PDE inhibitors in naïve mice may be mediated by enhanced release of small amounts of endogenous bimodally-acting (excitatory/inhibitory) opioid agonists by neurons in nociceptive networks. Ultra-low-dose NTX, nor-BNI or beta-FNA selectively antagonizes high-efficacy excitatory (hyperalgesic) Gs-coupled opioid receptor-mediated signaling in naïve mice and results in rapid conversion to inhibitory (analgesic) Gi/Go-coupled opioid receptor-mediated signaling which normally requires activation by much higher doses of opioid agonists. Cotreatment with a low subanalgesic dose of kelatorphan, an inhibitor of multiple endogenous opioid peptide-degrading enzymes, stabilizes endogenous opioid agonists released by cAMP-PDE inhibitors, resulting in conversion of the hyperalgesia to analgesia without requiring selective blockade of excitatory opioid receptor signaling. The present study provides a novel pharmacologic paradigm that may facilitate development of valuable non-narcotic clinical analgesics utilizing cotreatment with ultra-low-dose rolipram plus ultra-low-dose NTX or related agents.

Comparative pharmacokinetics of intravenous fentanyl and buprenorphine in healthy greyhound dogs.

PubMed

KuKanich, B; Allen, P

2014-12-01

The purpose of this study was to compare the pharmacokinetics of two highly protein-bound, lipophilic opioid drugs. Fentanyl (10 μg/kg) and buprenorphine (20 μg/kg) were administered intravenously (IV) to six healthy greyhound dogs (three males and three females). The doses were based on clinically administered doses for dogs. Plasma drug concentrations were determined using liquid chromatography with mass spectrometry, and noncompartmental pharmacokinetics were estimated with computer software. The volume of distribution (area) was larger for fentanyl (7.42 L/kg) compared to buprenorphine (3.54 L/kg). The plasma clearance of fentanyl (38.6 mL·min/kg) was faster than buprenorphine (10.3 mL·min/kg). The terminal half-life of fentanyl (2.22 h) was shorter than buprenorphine (3.96 h). Despite similar physicochemical properties including octanol-water partition coefficient and pKa, the pharmacokinetics of fentanyl and buprenorphine were not similar. Both fentanyl (84%) and buprenorphine (95-98%) are considered highly protein bound, but the differences in protein binding may contribute to the lack of similarity of pharmacokinetics in healthy dogs. © 2014 John Wiley & Sons Ltd.

Comparison of three chromatographic techniques for the detection of mitragynine and other indole and oxindole alkaloids in mitragyna speciosa (Kratom) plants

USDA-ARS?s Scientific Manuscript database

Leaves of the Southeast Asian plant Mitragyna speciosa (kratom) are used to suppress pain and mitigate opioid withdrawal syndromes. The potential threat of abuse and ready availability of this uncontrolled psychoactive plant material in the U.S. have led to the need for improved analytical technique...

Public sector low threshold office-based buprenorphine treatment: outcomes at year 7.

PubMed

Bhatraju, Elenore Patterson; Grossman, Ellie; Tofighi, Babak; McNeely, Jennifer; DiRocco, Danae; Flannery, Mara; Garment, Ann; Goldfeld, Keith; Gourevitch, Marc N; Lee, Joshua D

2017-02-28

Buprenorphine maintenance for opioid dependence remains of limited availability among underserved populations, despite increases in US opioid misuse and overdose deaths. Low threshold primary care treatment models including the use of unobserved, "home," buprenorphine induction may simplify initiation of care and improve access. Unobserved induction and long-term treatment outcomes have not been reported recently among large, naturalistic cohorts treated in low threshold safety net primary care settings. This prospective clinical registry cohort design estimated rates of induction-related adverse events, treatment retention, and urine opioid results for opioid dependent adults offered buprenorphine maintenance in a New York City public hospital primary care office-based practice from 2006 to 2013. This clinic relied on typical ambulatory care individual provider-patient visits, prescribed unobserved induction exclusively, saw patients no more than weekly, and did not require additional psychosocial treatment. Unobserved induction consisted of an in-person screening and diagnostic visit followed by a 1-week buprenorphine written prescription, with pamphlet, and telephone support. Primary outcomes analyzed were rates of induction-related adverse events (AE), week 1 drop-out, and long-term treatment retention. Factors associated with treatment retention were examined using a Cox proportional hazard model among inductions and all patients. Secondary outcomes included overall clinic retention, buprenorphine dosages, and urine sample results. Of the 485 total patients in our registry, 306 were inducted, and 179 were transfers already on buprenorphine. Post-induction (n = 306), week 1 drop-out was 17%. Rates of any induction-related AE were 12%; serious adverse events, 0%; precipitated withdrawal, 3%; prolonged withdrawal, 4%. Treatment retention was a median 38 weeks (range 0-320) for inductions, compared to 110 (0-354) weeks for transfers and 57 for the entire clinic population. Older age, later years of first clinic visit (vs. 2006-2007), and baseline heroin abstinence were associated with increased treatment retention overall. Unobserved "home" buprenorphine induction in a public sector primary care setting appeared a feasible and safe clinical practice. Post-induction treatment retention of a median 38 weeks was in line with previous naturalistic studies of real-world office-based opioid treatment. Low threshold treatment protocols, as compared to national guidelines, may compliment recently increased prescriber patient limits and expand access to buprenorphine among public sector opioid use disorder patients.

Effect of Nimodipine on Morphine-related Withdrawal Syndrome in Rat Model: An Observational Study

PubMed Central

Mishra, Pravash Ranjan; Barik, Mayadhar; Ray, Subrata Basu

2017-01-01

Objective: To observe the effect of L-type calcium channel blocker like nimodipine on morphine's withdrawal when it was administered continuously along with morphine versus a single bolus dose of nimodipine, which was administered at the end of the experiment before the precipitation of withdrawal reaction in morphine-dependent rats. Materials and Methods: Four groups of adult male Wistar rats were rendered morphine dependent by subcutaneous injections of morphine at a dose of 10 mg/kg for 10 days. Nimodipine 10 mg/kg intraperitoneally (ip) administered to one group once daily before morphine administration in the entire experimental period, and another group received nimodipine only once at the end of the experiment as a single bolus dose 2 mg/kg before the administration of naloxone. Naloxone 3 mg/kg was administered ip to all the groups to precipitate withdrawal reactions. The withdrawal reactions were evaluated and scored as per the Gellert and Holtzman global withdrawal rating scale. Results: Nimodipine when administered as a single bolus dose before naloxone administration in morphine-dependant rats reduced the features of withdrawal reactions more effectively than continuous administration of nimodipine along with morphine throughout the experimental period. Conclusion: We discovered that nimodipine helps in attenuating the severity of morphine withdrawal having potential role encountered during pharmacotherapy with morphine management of opioid dependence, well memory, impairement, cell signaling and phosphorylation of neuron. PMID:28553371

Effect of Nimodipine on Morphine-related Withdrawal Syndrome in Rat Model: An Observational Study.

PubMed

Mishra, Pravash Ranjan; Barik, Mayadhar; Ray, Subrata Basu

2017-01-01

To observe the effect of L-type calcium channel blocker like nimodipine on morphine's withdrawal when it was administered continuously along with morphine versus a single bolus dose of nimodipine, which was administered at the end of the experiment before the precipitation of withdrawal reaction in morphine-dependent rats. Four groups of adult male Wistar rats were rendered morphine dependent by subcutaneous injections of morphine at a dose of 10 mg/kg for 10 days. Nimodipine 10 mg/kg intraperitoneally (ip) administered to one group once daily before morphine administration in the entire experimental period, and another group received nimodipine only once at the end of the experiment as a single bolus dose 2 mg/kg before the administration of naloxone. Naloxone 3 mg/kg was administered ip to all the groups to precipitate withdrawal reactions. The withdrawal reactions were evaluated and scored as per the Gellert and Holtzman global withdrawal rating scale. Nimodipine when administered as a single bolus dose before naloxone administration in morphine-dependant rats reduced the features of withdrawal reactions more effectively than continuous administration of nimodipine along with morphine throughout the experimental period. We discovered that nimodipine helps in attenuating the severity of morphine withdrawal having potential role encountered during pharmacotherapy with morphine management of opioid dependence, well memory, impairement, cell signaling and phosphorylation of neuron.

Exploring Multitarget Interactions to Reduce Opiate Withdrawal Syndrome and Psychiatric Comorbidity

PubMed Central

2013-01-01

Opioid addiction is often characterized as a chronic relapsing condition due to the severe somatic and behavioral signs, associated with depressive disorders, triggered by opiate withdrawal. Since prolonged abstinence remains a major challenge, our interest has been addressed to such objective. Exploring multitarget interactions, the present investigation suggests that 3 or its (S)-enantiomer and 4, endowed with effective α2C-AR agonism/α2A-AR antagonism/5-HT1A-R agonism, or 7 and 9–11 producing efficacious α2C-AR agonism/α2A-AR antagonism/I2–IBS interaction might represent novel multifunctional tools potentially useful for reducing withdrawal syndrome and associated depression. Such agents, lacking in sedative side effects due to their α2A-AR antagonism, might afford an improvement over current therapies with clonidine-like drugs. PMID:24900763

Use of population pharmacokinetic modeling and Monte Carlo simulation to capture individual animal variability in the prediction of flunixin withdrawal times in cattle.

PubMed

Wu, H; Baynes, R E; Leavens, T; Tell, L A; Riviere, J E

2013-06-01

The objective of this study was to develop a population pharmacokinetic (PK) model and predict tissue residues and the withdrawal interval (WDI) of flunixin in cattle. Data were pooled from published PK studies in which flunixin was administered through various dosage regimens to diverse populations of cattle. A set of liver data used to establish the regulatory label withdrawal time (WDT) also were used in this study. Compartmental models with first-order absorption and elimination were fitted to plasma and liver concentrations by a population PK modeling approach. Monte Carlo simulations were performed with the population mean and variabilities of PK parameters to predict liver concentrations of flunixin. The PK of flunixin was described best by a 3-compartment model with an extra liver compartment. The WDI estimated in this study with liver data only was the same as the label WDT. However, a longer WDI was estimated when both plasma and liver data were included in the population PK model. This study questions the use of small groups of healthy animals to determine WDTs for drugs intended for administration to large diverse populations. This may warrant a reevaluation of the current procedure for establishing WDT to prevent violative residues of flunixin. © 2012 Blackwell Publishing Ltd.

An abuse-deterrent, microsphere-in-capsule formulation of extended-release oxycodone: alternative modes of administration to facilitate pain management in patients with dysphagia.

PubMed

McCarberg, Bill H; Kopecky, Ernest A; O'Connor, Melinda; Marseilles, Ann; Varanasi, Ravi K; Thompson, Christy; Fleming, Alison B

2016-12-01

Patients with chronic pain may experience difficulty swallowing, in part due to worsening disease, comorbid conditions, iatrogenic etiology, or age. Patients or caregivers may manipulate extended-release (ER) opioid formulations to facilitate oral dosing due to a lack of therapeutic options that allow for sprinkle or enteral feeding tube administration. If crushed or broken, current oral ER opioids can be associated with adverse sequelae, including risk of potentially fatal overdose. To review the safety, in vitro dissolution data, and in vivo pharmacokinetic data that support alternative modes of administration of oxycodone DETERx (Xtampza ER) via sprinkling onto soft foods for oral ingestion or via enteral feeding tubes. A review of oxycodone DETERx data from in vitro and in vivo studies was conducted to demonstrate support for alternative routes and modes of administration. There was no difference in the dissolution profile when administered with various soft foods or when mixed with various liquid vehicles and administered via nasogastric (NG) or gastrostomy (G) tubes, based on in vitro studies. When sprinkled onto applesauce and administered orally, the microspheres were bioequivalent to the intact oxycodone capsules. When crushed or chewed, the formulation maintained its pharmacokinetic profile; no bolus dose of opioid was released. The sprinkle-dose study was limited by the single-dose study design, as well as the small sample size. Oxycodone DETERx is the first ER oxycodone formulation that can be administered either intact, sprinkled onto soft foods, or via NG/G tubes, thereby providing options for treating pain in patients who have difficulty swallowing.

Pharmacokinetic-pharmacodynamic modeling of morphine-6-glucuronide-induced analgesia in healthy volunteers: absence of sex differences.

PubMed

Romberg, Raymonda; Olofsen, Erik; Sarton, Elise; den Hartigh, Jan; Taschner, Peter E M; Dahan, Albert

2004-01-01

Morphine-6-glucuronide (M6G) is a metabolite of morphine and a micro-opioid agonist. To quantify the potency and speed of onset-offset of M6G and explore putative sex dependency, the authors studied the pharmacokinetics and pharmacodynamics of M6G in volunteers using a placebo-controlled, randomized, double-blind study design. Ten men and 10 women received 0.3 mg/kg intravenous M6G and placebo (two thirds of the dose as bolus, one third as a continuous infusion over 1 h) on separate occasions. For 7 h, pain tolerance was measured using gradually increasing transcutaneous electrical stimulation, and blood samples were obtained. A population pharmacokinetic (inhibitory sigmoid Emax)-pharmacodynamic analysis was used to analyze M6G-induced changes in tolerated stimulus intensity. The improvement in model fits by inclusion of covariate sex was tested for significance. P values less than 0.01 were considered significant. Taking into account previous morphine data, a predictive pharmacokinetic-pharmacodynamic model was constructed to determine the contribution of M6G to morphine analgesia. M6G concentrations did not differ between men and women. M6G caused analgesia significantly greater than that observed with placebo (P < 0.01). The M6G analgesia data were well described by the pharmacokinetic-pharmacodynamic model. The M6G effect site concentration causing a 25% increase in current (C25) was 275 +/- 135 nm (population estimate +/- SE), the blood effect site equilibration half-life was 6.2 +/- 3.3 h, and the steepness parameter was 0.71 +/- 0.18. Intersubject variability was 167% for C25 and 218% for the effect half-life. None of the model parameters showed sex dependency. A cumulative dose of 0.3 mg/kg M6G, given over 1 h, produces long-term analgesia greater than that observed with placebo, with equal dynamics (potency and speed of onset-offset) in men and women. Possible causes for the great intersubject response variability, such as genetic polymorphism of the micro-opioid receptor and placebo-related phenomena, are discussed. The predictive pharmacokinetic-pharmacodynamic model was applied successfully and was used to estimate M6G analgesia after morphine in patients with normal and impaired renal function.

In-vitro and in-vivo characterization of a buprenorphine delivery system.

PubMed

Kleppner, Sofie R; Patel, Raj; McDonough, Joseph; Costantini, Lauren C

2006-03-01

Buprenorphine is a mu-opioid receptor partial agonist with enhanced safety and comparable efficacy to methadone for treatment of opioid dependence. The sublingual formulation of buprenorphine, approved for treatment of opioid dependence, produces variable buprenorphine blood levels and requires frequent dosing that limits patient compliance. To achieve stable buprenorphine levels that may improve patient outcome, an implantable sustained buprenorphine delivery system was developed. Each implant consists of ethylene vinyl acetate copolymer and 90 mg buprenorphine HCl, and measures 26 mm in length and 2.4 mm in diameter. Steady-state release in-vitro was 0.5 mg/implant/day. In-vivo pharmacokinetics and safety were examined for up to 52 weeks in beagle dogs receiving 8, 16 or 24 subcutaneous implants. Plasma buprenorphine concentrations correlated with the number of implants administered. Peak buprenorphine concentrations were generally reached within 24 h after implantation. Steady-state plasma levels were attained between 3 and 8 weeks, and were maintained for study duration, with a calculated mean release rate of 0.14+/-0.04 mg/implant/day. There were no test-article-related adverse effects. This delivery system can provide long-term stable systemic buprenorphine levels, and may increase patient compliance, thereby improving outcome for opioid-dependent patients.

Physiological, pharmacokinetic and liver metabolism comparisons between 3-, 6-, 12- and 18-month-old male Sprague Dawley rats under ketamine-xylazine anesthesia

PubMed Central

Giroux, Marie-Chantal; Santamaria, Raphael; Hélie, Pierre; Burns, Patrick; Beaudry, Francis; Vachon, Pascal

2015-01-01

The main objective of this study was to compare the physiological changes (withdrawal and corneal reflexes, respiratory and cardiac frequency, blood oxygen saturation, and rectal temperature) following intraperitoneal administration of ketamine (80 mg/kg) and xylazine (10 mg/kg) to 3-, 6-, 12- and 18-month-old male Sprague Dawley rats (n=6/age group). Plasma pharmacokinetics, liver metabolism, and blood biochemistry were examined for a limited number of animals to better explain anesthetic drug effects. Selected organs were collected for histopathology. The results for the withdrawal and corneal reflexes suggest a shorter duration and decreased depth of anesthesia with aging. Significant cardiac and respiratory depression, as well as decreased blood oxygen saturation, occurred in all age groups however, cardiac frequency was the most affected parameter with aging, since the 6-, 12-, and 18-month-old animals did not recuperate to normal values during recovery from anesthesia. Pharmacokinetic parameters (T1/2 and AUC) increased and drug clearance decreased with aging, which strongly suggests that drug exposure is associated with the physiological results. The findings for liver S9 fractions of 18-month-old rats compared with the other age groups suggest that following a normal ketamine anesthetic dose (80 mg/kg), drug metabolism is impaired, leading to a significant increase of drug exposure. In conclusion, age and related factors have a substantial effect on ketamine and xylazine availability, which is reflected by significant changes in pharmacokinetics and liver metabolism of these drugs, and this translates into shorter and less effective anesthesia with increasing age. PMID:26489361

Central effects of ethanol interact with endogenous mu opioid activity to control isolation-induced analgesia in maternally separated infant rats

PubMed Central

Nizhnikov, Michael E.; Kozlov, Andrey P.; Kramskaya, Tatiana. A.; Varlinskaya, Elena I.; Spear, Norman E.

2014-01-01

Endogenous opioid activity plays an important role in ethanol consumption and reinforcement in infant rats. Opioid systems are also involved in mediation and regulation of stress responses. Social isolation is a stressful experience for preweanling rats and changes the effects of ethanol through opioid-dependent mechanisms. The present study assessed effects of intracisternal (i.c.) administration of a selective mu-opioid antagonist (CTOP) and i.p. administration of a nonspecific opioid antagonist (naloxone) on voluntary intake and behavior in socially isolated 12–day-old (P12) pups treated with 0.5 g/kg ethanol. Voluntary intake of 0.1% saccharin or water, locomotion, rearing activity, paw licking and grooming were assessed during short-term isolation from littermates (STSI; 8-min duration). Thermal nociceptive reactivity was measured before and after this intake test, with normalized differences between pre- and post-test latencies of paw withdrawal from a hot plate (49°C) used as an index of isolation-induced analgesia (IIA). Results indicated several effects of social isolation and ethanol mediated through the mu-opioid system. Effects of low dose ethanol (0.5 g/kg) and voluntary consumption of saccharin interacted with endogenous mu-opioid activity associated with STSI. Blockade of mu-opioid receptors on saccharin consumption and paw licking-grooming affected intoxicated animals. Low dose ethanol and ingestion of saccharin blunted effects of CTOP on rearing behavior and nociceptive reactivity. Central injections of CTOP stimulated paw licking and grooming dependent on ethanol dose and type of fluid ingested. Ethanol selectively increased saccharin intake during STSI in females, naloxone and CTOP blocked ethanol–mediated enhancement of saccharin intake. We suggest that enhancement of saccharin intake by ethanol during STSI is the product of synergism between isolation-induced mu- opioid activity that increases the pup’s sensitivity to appetitive taste stimulation and the anxiolytic effects of 0.5 g/kg ethanol that decreases behaviors otherwise competing with independent ingestive activity. PMID:24315831

Increased thermal pain sensitivity in animals exposed to chronic high dose Vicodin but not pure hydrocodone.

PubMed

O'Connell, Thomas F; Carpenter, Patrick S; Caballero, Nadia; Putnam, Andrew J; Steere, Joshua T; Matz, Gregory J; Foecking, Eileen M

2014-01-01

Vicodin, the combination drug of acetaminophen and the opioid hydrocodone, is one of the most prescribed drugs on the market today. Opioids have demonstrated the ability to paradoxically cause increased pain sensitivity to users in a phenomena called opioid-induced hyperalgesia (OIH). While selected opioids have been shown to produce OIH symptoms in an animal model, hydrocodone and the combination drug Vicodin have yet to be studied. The purpose of this study was to explore the effect of exposure to chronic high dose Vicodin or its components on the sensitivity to both thermal and mechanical pain. Animals were randomly divided into 4 groups, Vicodin, acetaminophen, hydrocodone, or vehicle control, and administered the drug daily for 120 days. Rats were subsequently tested for thermal and mechanical sensitivity. The rats in the Vicodin group displayed a significant decrease in withdrawal time to thermal pain. The rats receiving acetaminophen, hydrocodone, and vehicle showed no statistically significant hypersensitivity in thermal testing. None of the groups demonstrated statistically significant hypersensitivity to mechanical testing. The data suggests Vicodin produces signs of OIH in a rodent model. However, increased pain sensitivity was only noted in the thermal pathway and the hypersensitivity was only seen with the opioid combination drug, not the opioid alone. The results of this study both support the results of previous rodent opioid studies while generating further questions about the specific properties of Vicodin that contribute to pain hypersensitivity. The growing use of Vicodin to treat chronic pain necessitates further research looking into this paradoxical pain response.

Methadone patients exhibit increased startle and cortisol response after intravenous yohimbine.

PubMed

Stine, S M; Grillon, C G; Morgan, C A; Kosten, T R; Charney, D S; Krystal, J H

2001-03-01

Brain noradrenergic systems have been shown to be altered in opioid dependence and to mediate aspects of opioid withdrawal. Pre-clinical and clinical studies by others have shown that yohimbine, which increases noradrenergic activity, also increases both baseline and fear enhancement of the magnitude of the acoustic startle response (ASR). In a separate report from this experiment, it was shown that yohimbine produced opioid withdrawal-like symptoms, including anxiety, in clinically stable methadone-maintained patients and also produced elevations in the norepinepherine (NE) metabolite, 3-methoxy-4 hydroxyphenethyleneglycol (MHPG), and cortisol serum levels. The current study reports the effects of intravenous yohimbine hydrochloride, 0.4 mg/kg versus saline (double-blind), on ASR magnitude, plasma MHPG, and cortisol levels in eight methadone-maintained patients and 13 healthy subjects in a double-blind fashion. Yohimbine increased startle magnitude in both groups. There was no basal (placebo day) difference between the startle response of the two groups, but methadone patients had a larger startle magnitude increase in response to yohimbine than healthy controls. Methadone-maintained patients had lower baseline plasma levels of MHPG and similar baseline plasma cortisol levels compared with normal subjects. Yohimbine caused significant elevation in cortisol and MHPG in both groups. Methadone-maintained subjects had higher elevations in cortisol levels and MHPG (methadone main effect) levels in response to yohimbine. However, when MHPG levels were corrected for baseline differences by analysis of covariance (ANCOVA), the yohimbine effect, but not the methadone effect remained statistically significant. These results are consistent with the previous report and support the hypothesis that abnormalities of the hypothalamic-pituitary-adrenal (HPA) axis and of noradrenergic mechanisms of stress response persist in opioid-agonist maintenance. The ASR effect extends the previous report and provides an additional objective measure for perturbation of noradrenergic and stress responses in these patients.

Oral opioid administration and hyperalgesia in patients with cancer or chronic nonmalignant pain

PubMed Central

Reznikov, Igor; Pud, Dorit; Eisenberg, Elon

2005-01-01

Aims Previous research has reported on reduced paw withdrawal latencies to heat and mechanical stimuli after parenteral administration of opioids in animals and on increased pain sensitivity in humans subsequent to postoperative infusions of short-acting opioids or in drug addicts. The aim of the present study was to explore the possibility that oral opioid treated patients with cancer-related or chronic nonmalignant pain differ in their pain sensitivity from patients treated with non-opioid analgesics. Methods The study population consisted of 224 patients, including 142 in the opioid-treated group and 82 in the non-opioid-treated group. Pain thresholds for punctuate measured by von Frey filaments (g), mechanical pressure measured by pressure algometer (mmHg), heat stimuli measured by quantitative sensory testing (°C), as well as suprathreshold tonic heat pain intensity (46.5 °C for 1 min) measured by 0–10 numerical pain scale (NPS) were obtained at a nonpainful site (thenar eminence) in all patients. Results No differences between the groups were found for gender, age, duration of pain, or duration of treatment (independent variables). No significant differences between the groups were found in punctuate (difference = 17.0 g (95% CI −8.8, 42.8), P = 0.19), pressure (2.2 mmHg (−28.7, 33.2), P = 0.89) and heat (−0.3 °C (−1.5, 0.9), P = 0.70) pain thresholds, or in suprathreshold heat pain intensity (difference between maximal pain intensities −0.4 NPS units (95% CI −1.2, 0.4), P = 0.31). Pearson correlations within the opioid-treated group failed to show significant relationships between any of the independent variables and the outcome measures. A further comparison of the outcomes between the ‘weak’ opioid-treated subgroup and the ‘strong’ opioid-treated subgroup again revealed insignificant results. Conclusions These results suggest that the administration of ‘commonly used’ dosages of oral opioids does not result in abnormal pain sensitivity beyond that of patients receiving non-opioid analgesia. PMID:16120071

Population pharmacokinetics of oxycodone in patients with cancer-related pain.

PubMed

Komatsu, Toshiaki; Kokubun, Hideya; Suzuki, Ai; Takayanagi, Risa; Yamada, Yasuhiko; Matoba, Motohiro; Yago, Kazuo

2012-09-01

Oxycodone is an opioid widely prescribed to cancer patients for pain relief. However, the pharmacokinetics of oxycodone has not been sufficiently examined. Therefore the aim of this work was to study population pharmacokinetics of oxycodone in patients with cancer pain. The authors analyzed 108 serum oxycodone samples of 33 individuals with nonlinear mixed-effects model (NONMEM). Population pharmacokinetics was calculated using the one-compartment model of clearance, volume of distribution, bioavailability, absorption constant rate, and lag time. An exponential error model was used to determine interindividual variability and a relative error model was applied to assess residual variability. Population pharmacokinetics of oxycodone at the end point were as follows: CL(L/h) = 10.7 × [1 + (2 - Child-Pugh Classification)] (Class: A = 0, B = 1, C = 2); V(d) (L) = 193; k(a) (h(-1)) = 0.336; T(lag) (h) = 0.859; F (%) = 63.9. Interindividual variability was CL: 30.5%, V(d): 44.6%, and F: 37.0%, and residual variability was 16.2%. As the total clearance in patients with liver dysfunction (Child-Pugh class B) was reduced to 33.3%, serum concentration of oxycodone increased by 1.5. Therefore, it became clear that dose adjustments are essential when treating patients with liver dysfunction. These findings suggest that population parameters are useful for evaluating pharmacokinetics of oxycodone in patients with cancer pain.

Maximizing value in opioid utilization: Is oxycodone immediate release a good option for pain management?

PubMed

Pergolizzi, Joseph V; Köknel Talu, Gül; Zmponga, Gianpetrio; Erdine, Serdar; Taylor, Robert; Ayan, Burak; Raffa, Robert B

2015-01-01

The modern approach to the management of pain involves optimizing all aspects of the process. This includes utilization of pharmacologic and non-pharmacologic modalities, consideration of patient characteristics, proper matching of the physiology of the pain with the analgesic's mechanism of action (pharmacodynamics, PD), and the onset and duration of action (pharmacokinetics, PK). No single agent or formulation satisfies all of the requirements for all patients. Aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) are effective options for inflammatory pain and, as is acetaminophen, for mild pain. Specialized agents are helpful for particular pains, such as for migraine headache. Opioids remain the standard option for severe pain. Although they are generally a safe and effective option, opioids can produce dose-limiting adverse effects and have abuse potential. The goal of pain therapy is thus to achieve the maximum pain relief with the least amount of opioid exposure. Against this background of measured approach to the use of analgesics, an immediate release (IR) oral formulation of the established opioid oxycodone has been developed to provide rapid onset of action and rate of titration, both of which could maximize temporal matching of dose with pain level and reduce total exposure to drug. This article considers the option of an immediate release (IR) oral formulation for the management of pain.

Development of a physiologically based pharmacokinetic model for flunixin in cattle (Bos taurus)

USDA-ARS?s Scientific Manuscript database

Violative residues of flunixin in tissues from bob veal calves and cull dairy cows has been attributed to noncompliance with the FDA-approved route of administration and withdrawal time, however, the effect of administration route and physiological differences among animals on tissue residue depleti...

Traditional Chinese and Indian medicine in the treatment of opioid-dependence: a review

PubMed Central

Doosti, Fatemeh; Dashti, Saeedeh; Tabatabai, Seyed Meghdad; Hosseinzadeh, Hossein

2013-01-01

Objective: In this study, the current literatures on the use of herbs and herbal preparations of Traditional Chinese and Indian Medicine for the treatment of opioid addiction were reviewed. Matherials and Methods: Search was done in databases such as Pub Med, Science Direct, Scopus, Springer Link, and Google Scholar. Results: Among 18 retrieved studies, 3 studies were about asafetida extract, an approved preparation for ameliorating drug abstinence in China. Chinese preparations including Composite Dong Yuan Gao, Qingjunyin and TJ-97 (a water extract of dai-bofu-to) as well as Indian ones, Mentate and Shilajit, were reported to have positive effects against opioid withdrawal, dependence, and tolerance. Moreover, Levo-tetrahydropalmatine and L-Stepholidine, in addition to extracts of Caulis Sinomenii and Sinomenium acutum showed similar effects. Banxia Houpu Decoction, Fu-Yuan pellet, Jinniu capsules, Qingjunyin, Tai-Kang-Ning capsule, and Xuan Xia Qudu Jiaonang (WeiniCom) from Chinese preparations, showed anti-addiction effects in randomized, double-blind and, in some studies, multicenter clinical trials. Conclusion : Traditional herbal preparations of China and India have anti-addiction effects with less adverse effects than alpha2-adrenergic or opioid agonists. PMID:25050276

"Weak" opioid analgesics. Codeine, dihydrocodeine and tramadol: no less risky than morphine.

PubMed

2016-02-01

So-called weak opioid analgesics are often used to treat severe pain, or when paracetamol or a nonsteroidal anti-inflammatory drug (NSAID) proves inadequate. But are weak opioids any more effective than paracetamol or NSAIDs on nociceptive pain, and are they better tolerated than morphine? To answer these questions, we conducted a review of literature using the standard Prescrire methodology. The potency of codeine and tramadol is strongly influenced by the cytochrome P450 isoenzyme CYP2D6 genotype, which varies widely from one person to another. This explains reports of overdosing or underdosing after administration of standard doses of the two drugs. The potency of morphine and that of buprenorphine, an opioid receptor agonist-antagonist, appears to be independent of CYP2D6 activity. All "weak" opioids can have the same dose-dependent adverse effects as morphine. There is no evidence that, at equivalent analgesic efficacy, weak opioids carry a lower risk of addiction than low-dose morphine. Respiratory depression can occur in ultrarapid metabolisers after brief exposure to standard doses of codeine or tramadol. Similar cases have been reported with dihydrocodeine in patients with renal failure. In addition, tramadol can cause a serotonin syndrome, hypoglycaemia, hyponatraemia and seizures. Several trials have compared different weak opioids in patients with post-operative pain. A single dose of a weak opioid, possibly combined with paracetamol, has greater analgesic efficacy than paracetamol alone but is not more effective than an NSAID alone. There is a dearth of evidence on weak opioids in patients with chronic pain. Available trials fail to show that a weak opioid has markedly superior analgesic efficacy to paracetamol or an NSAID. Sublingual buprenorphine at analgesic doses appears less likely to cause respiratory depression, but it seems to have weak analgesic efficacy. In practice, when opioid therapy is needed, there is no evidence that codeine, dihydrocodeine or tramadol is less risky than morphine at its lowest effective dose. Compared to morphine, the efficacy of these drugs varies more from one patient to another, and their multiple pharmacokinetic interactions can be difficult to manage. There is also a sometimes unpredictable risk of serious over-dose. Tramadol has additional adverse effects unrelated to its opioid effects. Weak opioids require at least as much vigilance as morphine, despite the major differences in their reputation and regulation.

Regulated endocytosis of opioid receptors: cellular mechanisms and proposed roles in physiological adaptation to opiate drugs.

PubMed

von Zastrow, Mark; Svingos, Adena; Haberstock-Debic, Helena; Evans, Chris

2003-06-01

Opiate drugs such as morphine and heroin are among the most effective analgesics known. Prolonged or repeated administration of opiates produces adaptive changes in the nervous system that lead to reduced drug potency or efficacy (tolerance), as well as physiological withdrawal symptoms and behavioral manifestations such as craving when drug use is terminated (dependence). These adaptations limit the therapeutic utility of opiate drugs, particularly in the treatment of chronically painful conditions, and are thought to contribute to the highly addictive nature of opiates. For many years it has been proposed that physiological tolerance to opiate drugs is associated with a modification of the number or functional activity of opioid receptors in specific neurons. We now understand certain mechanisms of opioid receptor desensitization and endocytosis in considerable detail. However, the functional roles that these mechanisms play in the complex physiological adaptation of the intact nervous system to opiates are only beginning to be explored.

Mathematical modeling and simulation in animal health - Part II: principles, methods, applications, and value of physiologically based pharmacokinetic modeling in veterinary medicine and food safety assessment.

PubMed

Lin, Z; Gehring, R; Mochel, J P; Lavé, T; Riviere, J E

2016-10-01

This review provides a tutorial for individuals interested in quantitative veterinary pharmacology and toxicology and offers a basis for establishing guidelines for physiologically based pharmacokinetic (PBPK) model development and application in veterinary medicine. This is important as the application of PBPK modeling in veterinary medicine has evolved over the past two decades. PBPK models can be used to predict drug tissue residues and withdrawal times in food-producing animals, to estimate chemical concentrations at the site of action and target organ toxicity to aid risk assessment of environmental contaminants and/or drugs in both domestic animals and wildlife, as well as to help design therapeutic regimens for veterinary drugs. This review provides a comprehensive summary of PBPK modeling principles, model development methodology, and the current applications in veterinary medicine, with a focus on predictions of drug tissue residues and withdrawal times in food-producing animals. The advantages and disadvantages of PBPK modeling compared to other pharmacokinetic modeling approaches (i.e., classical compartmental/noncompartmental modeling, nonlinear mixed-effects modeling, and interspecies allometric scaling) are further presented. The review finally discusses contemporary challenges and our perspectives on model documentation, evaluation criteria, quality improvement, and offers solutions to increase model acceptance and applications in veterinary pharmacology and toxicology. © 2016 John Wiley & Sons Ltd.

Antibiotics in Animal Products

NASA Astrophysics Data System (ADS)

Falcão, Amílcar C.

The administration of antibiotics to animals to prevent or treat diseases led us to be concerned about the impact of these antibiotics on human health. In fact, animal products could be a potential vehicle to transfer drugs to humans. Using appropri ated mathematical and statistical models, one can predict the kinetic profile of drugs and their metabolites and, consequently, develop preventive procedures regarding drug transmission (i.e., determination of appropriate withdrawal periods). Nevertheless, in the present chapter the mathematical and statistical concepts for data interpretation are strictly given to allow understanding of some basic pharma-cokinetic principles and to illustrate the determination of withdrawal periods

The corticotropin-releasing factor receptor-1 pathway mediates the negative affective states of opiate withdrawal.

PubMed

Contarino, Angelo; Papaleo, Francesco

2005-12-20

The negative affective symptoms of opiate withdrawal powerfully motivate drug-seeking behavior and may trigger relapse to heroin abuse. To date, no medications exist that effectively relieve the negative affective symptoms of opiate withdrawal. The corticotropin-releasing factor (CRF) system has been hypothesized to mediate the motivational effects of drug dependence. The CRF signal is transmitted by two distinct receptors named CRF receptor-1 (CRF1) and CRF2. Here we report that genetic disruption of CRF1 receptor pathways in mice eliminates the negative affective states of opiate withdrawal. In particular, neither CRF1 receptor heterozygous (CRF1+/-) nor homozygous (CRF1-/-) null mutant mice avoided environmental cues repeatedly paired with the early phase of opiate withdrawal. These results were not due to altered associative learning processes because CRF1+/- and CRF1-/- mice displayed reliable, conditioned place aversions to environmental cues paired with the kappa-opioid receptor agonist U-50,488H. We also examined the impact of CRF1 receptor-deficiency upon opiate withdrawal-induced dynorphin activity in the nucleus accumbens, a brain molecular mechanism thought to underlie the negative affective states of drug withdrawal. Consistent with the behavioral indices, we found that, during the early phase of opiate withdrawal, neither CRF1+/- nor CRF1-/- showed increased dynorphin mRNA levels in the nucleus accumbens. This study reveals a cardinal role for CRF/CRF1 receptor pathways in the negative affective states of opiate withdrawal and suggests therapeutic strategies for the treatment of opiate addiction.

Pharmacokinetics and -dynamics of intramuscular and intranasal naloxone: an explorative study in healthy volunteers.

PubMed

Skulberg, Arne Kristian; Tylleskar, Ida; Nilsen, Turid; Skarra, Sissel; Salvesen, Øyvind; Sand, Trond; Loftsson, Thorsteinn; Dale, Ola

2018-03-22

This study aimed to develop a model for pharmacodynamic and pharmacokinetic studies of naloxone antagonism under steady-state opioid agonism and to compare a high-concentration/low-volume intranasal naloxone formulation 8 mg/ml to intramuscular 0.8 mg. Two-way crossover in 12 healthy volunteers receiving naloxone while receiving remifentanil by a target-controlled infusion for 102 min. The group were subdivided into three different doses of remifentanil. Blood samples for serum naloxone concentrations, pupillometry and heat pain threshold were measured. The relative bioavailability of intranasal to intramuscular naloxone was 0.75. Pupillometry showed difference in antagonism; the effect was significant in the data set as a whole (p < 0.001) and in all three subgroups (p < 0.02-p < 0.001). Heat pain threshold showed no statistical difference. A target-controlled infusion of remifentanil provides good conditions for studying the pharmacodynamics of naloxone, and pupillometry was a better modality than heat pain threshold. Intranasal naloxone 0.8 mg is inferior for a similar dose intramuscular. Our design may help to bridge the gap between studies in healthy volunteers and the patient population in need of naloxone for opioid overdose. clinicaltrials.gov : NCT02307721.

Novel opioid cyclic tetrapeptides: Trp isomers of CJ-15,208 exhibit distinct opioid receptor agonism and short-acting κ opioid receptor antagonism.

PubMed

Ross, Nicolette C; Reilley, Kate J; Murray, Thomas F; Aldrich, Jane V; McLaughlin, Jay P

2012-02-01

The κ opioid receptor antagonists demonstrate potential for maintaining abstinence from psychostimulant abuse, but existing non-peptide κ-receptor selective antagonists show exceptionally long activity. We hypothesized that the L- and D-Trp isomers of CJ-15,208, a natural cyclic tetrapeptide reported to be a κ-receptor antagonist in vitro, would demonstrate short-acting, dose-dependent antagonism in vivo, preventing reinstatement of cocaine-seeking behaviour. Affinity, selectivity and efficacy of the L-Trp and D-Trp isomers for opioid receptors were assessed in vitro in radioligand and GTPγS binding assays. Opioid receptor agonist and antagonist activities were characterized in vivo following i.c.v. administration with the 55°C warm water tail-withdrawal assay. The D-Trp isomer, which demonstrated primarily κ-receptor selective antagonist activity, was further evaluated for its prevention of stress- and drug-induced reinstatement of extinguished cocaine conditioned place preference (CPP). The two isomers showed similar affinity and selectivity for κ receptors (K(i)  30-35 nM) as well as κ receptor antagonism in vitro. As expected, the D-Trp cyclic tetrapeptide exhibited minimal agonist activity and induced dose-dependent κ-receptor selective antagonism lasting less than 18 h in vivo. Pretreatment with this peptide prevented stress-, but not cocaine-induced, reinstatement of extinguished cocaine CPP. In contrast, the L-Trp cyclic tetrapeptide unexpectedly demonstrated mixed opioid agonist/antagonist activity. The L-Trp and the D-Trp isomers of CJ-15,208 demonstrate stereospecific opioid activity in vivo. The relatively brief κ opioid receptor antagonism, coupled with the prevention of stress-induced reinstatement of extinguished cocaine-seeking behaviour, suggests the D-Trp isomer could be used therapeutically to maintain abstinence from psychostimulant abuse. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

Low-Dose Cannabinoid Type 2 Receptor Agonist Attenuates Tolerance to Repeated Morphine Administration via Regulating μ-Opioid Receptor Expression in Walker 256 Tumor-Bearing Rats.

PubMed

Zhang, Mingyue; Wang, Kun; Ma, Min; Tian, Songyu; Wei, Na; Wang, Guonian

2016-04-01

Morphine is widely used in patients with moderate and severe cancer pain, whereas the development of drug tolerance remains a major problem associated with opioid use. Previous studies have shown that cannabinoid type 2 (CB2) receptor agonists induce morphine analgesia, attenuate morphine tolerance in normal and neuropathic pain animals, induce transcription of the μ-opioid receptor (MOR) gene in Jurkat T cells, and increase morphine analgesia in cancer pain animals. However, no studies of the effects of CB2 receptor agonists on morphine tolerance in cancer pain have been performed. Therefore, we investigated the effect of repeated intrathecal (IT) injection of the low-dose CB2 receptor agonist AM1241 on the development of morphine tolerance in walker 256 tumor-bearing rats. We also tested the influence of the CB2 receptor agonist AM1241 on MOR protein and messenger ribonucleic acid (mRNA) expression in the rat spinal cord and dorsal root ganglia (DRG). Walker 256 cells were implanted into the plantar region of each rat's right hindpaw. Tumor-bearing rats received IT injection of the CB2 receptor agonist AM1241 or antagonist AM630 with or without morphine subcutaneously twice daily for 8 days. Rats receiving drug vehicle only served as the control group. Mechanical paw withdrawal threshold and thermal paw withdrawal latency were assessed by a von Frey test and hot plate test 30 minutes after drug administration every day. MOR protein and mRNA expression in the spinal cord and DRG were detected after the last day (day 8) of drug administration via Western blot and real-time reverse transcription polymerase chain reaction. The data were analyzed via analysis of variance followed by Student t test with Bonferroni correction for multiple comparisons. Repeated morphine treatments reduced the mechanical withdrawal threshold and thermal latency. Coadministration of a nonanalgetic dose of the CB2 receptor agonist AM1241 with morphine significantly inhibited the development of morphine tolerance and increased the MOR protein expression in the spinal cord and DRG and mRNA expression in the spinal cord in tumor-bearing rats. Our findings indicate that IT injection of a nonanalgetic dose of a CB2 receptor agonist increased the analgesia effect and alleviated tolerance to morphine in tumor-bearing rats, potentially by regulating MOR expression in the spinal cord and DRG. This receptor may be a new target for prevention of the development of opioid tolerance in cancer pain.

Association of an Opioid Standard of Practice Intervention With Intravenous Opioid Exposure in Hospitalized Patients.

PubMed

Ackerman, Adam L; O'Connor, Patrick G; Doyle, Deirdre L; Marranca, Sheyla M; Haight, Carolyn L; Day, Christine E; Fogerty, Robert L

2018-06-01

Opioids are commonly used to treat pain in hospitalized patients; however, intravenous administration carries an increased risk of adverse effects compared with oral administration. The subcutaneous route is an effective method of opioid delivery with favorable pharmacokinetics. To assess an intervention to reduce intravenous opioid use, total parenteral opioid exposure, and the rate of patients administered parenteral opioids. A pilot study was conducted in an adult general medical unit in an urban academic medical center. Attending physicians, nurse practitioners, and physician assistants who prescribed drugs were the participants. Use of opioids was compared between a 6-month control period and 3 months following education for the prescribers on opioid routes of administration. Adoption of a local opioid standard of practice, preferring the oral and subcutaneous routes over intravenous administration, and education for prescribers and nursing staff on awareness of the subcutaneous route was implemented. The primary outcome was a reduction in intravenous doses administered per patient-day. Secondary measures included total parenteral and overall opioid doses per patient-day, parenteral and overall opioid exposure per patient-day, and daily rate of patients receiving parenteral opioids. Pain scores were measured on a standard 0- to 10-point Likert scale over the first 5 days of hospitalization. The control period included 4500 patient-days, and the intervention period included 2459 patient-days. Of 127 patients in the intervention group, 59 (46.5%) were men; mean (SD) age was 57.6 (18.5) years. Intravenous opioid doses were reduced by 84% (0.06 vs 0.39 doses per patient-day, P < .001), and doses of all parenteral opioids were reduced by 55% (0.18 vs 0.39 doses per patient-day, P < .001). In addition, mean (SD) daily parenteral opioid exposure decreased by 49% (2.88 [0.72] vs 5.67 [1.14] morphine-milligram equivalents [MMEs] per patient-day). The daily rate of patients administered any parenteral opioid decreased by 57% (6% vs 14%; P < .001). Doses of opioids given by oral or parenteral route were reduced by 23% (0.73 vs 0.95 doses per patient-day, P = .02), and mean daily overall opioid exposure decreased by 31% (6.30 [4.12] vs 9.11 [7.34] MMEs per patient-day). For hospital days 1 through 3, there were no significant postintervention vs preintervention differences in mean reported pain score for patients receiving opioid therapy: day 1, -0.19 (95% CI, -0.94 to 0.56); day 2, -0.49 (95% CI, -1.01 to 0.03); and day 3, -0.54 (95% CI, -1.18 to 0.09). However, significant improvement was seen in the intervention group on days 4 (-1.07; 95% CI, -1.80 to -0.34) and 5 (-1.06; 95% CI, -1.84 to -0.27). An intervention targeting the use of intravenous opioids may be associated with reduced opioid exposure while providing effective pain control to hospitalized adults.

[Mechanisms of opioid-induced overdose: experimental approach to clinical concerns].

PubMed

Baud, F-J

2009-09-01

The widely used term "overdose" denotes a toxic effect: opioid-induced intoxication and a mechanism: the poisoning results only from an overdose. Surprisingly, our understanding of the pathophysiology of this deadly complication is limited. In drug users, we attempted to: (1) improve knowledge of drug-induced respiratory effects; (2) clarify the mechanisms of drug interactions; (3) identify factors of variability and vulnerability. A prospective study of opioid overdoses confirmed that poisonings involving buprenorphine do exist. However, the mechanisms of buprenorphine poisoning are more complex than only an overdose, particularly the severity is less than that induced by heroin. In contrast, methadone overdose is life-threatening. Experimental studies addressed several clinical questions and also showed limited discrepancies. At pharmacological doses, opioids decrease the ventilatory response to CO(2). However, this effect does not account for the morbimortality of opioid poisonings. The mechanisms of opioid-induced morbimortality are different. Buprenorphine at doses near its median lethal dose did not induce acute respiratory failure as defined by a decrease in the partial pressure of oxygen in arterial blood (PaO(2)). In contrast, the combination of buprenorphine with flunitrazepam results in a decrease in PaO(2). This harmful interaction does not exist with other benzodiazepines in the rat, except for very high doses of nordazepam. The interaction results from a pharmacokinetic process. In contrast, methadone causes a dose-dependent decrease in PaO(2,) even significant before hypercapnia. We are assessing the relationships between on one hand alterations of ventilatory pattern and of arterial blood gas and on the other hand the different types of opiate receptors in the rats.

Impaired diffuse noxious inhibitory controls in specific alternation of rhythm in temperature-stressed rats.

PubMed

Itomi, Yasuo; Tsukimi, Yasuhiro; Kawamura, Toru

2016-08-05

Fibromyalgia is characterized by chronic widespread musculoskeletal pain. A hypofunction in descending pain inhibitory systems is considered to be involved in the chronic pain of fibromyalgia. We examined functional changes in descending pain inhibitory systems in rats with specific alternation of rhythm in temperature (SART) stress, by measuring the strength of diffuse noxious inhibitory controls (DNIC). Hindpaw withdrawal thresholds to mechanical von Frey filament or fiber-specific electrical stimuli by the Neurometer system were used to measure the pain response. To induce DNIC, capsaicin was injected into the intraplantar of the forepaw. SART-stressed rats were established by exposure to repeated cold stress for 4 days. In the control rats, heterotopic intraplantar capsaicin injection increased withdrawal threshold, indicative of analgesia by DNIC. The strength of DNIC was reduced by naloxone (μ-opioid receptor antagonist, intraperitoneally and intracerebroventricularly), yohimbine (α2-adrenoceptor antagonist, intrathecally), and WAY-100635 (5-HT1A receptor antagonist, intrathecally) in the von Frey test. In SART-stressed rats, capsaicin injection did not increase withdrawal threshold in the von Frey test, indicating deficits in DNIC. In the Neurometer test, deficient DNIC in SART-stressed rats were observed only for Aδ- and C-fibers, but not Aβ-fibers stimulation. Analgesic effect of intracerebroventricular morphine was markedly reduced in SART-stressed rats compared with the control rats. Taken together, in SART-stressed rats, capsaicin-induced DNIC were deficient, and a hypofunction of opioid-mediated central pain modulation system may cause the DNIC deficit. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of tizanidine and morphine with regard to tolerance-developing ability to antinociceptive action.

PubMed

Nabeshima, T; Yamada, S; Sugimoto, A; Matsuno, K; Kameyama, T

1986-10-01

The antinociceptive, tolerance-developing and anti-withdrawal activities of tizanidine [5-chloro-4-(2-imidazolin-2-yl-amino)-2,1,3-benzo-thiadiazole] were investigated by comparing its effects with those of morphine and clonidine in tail-flick-, hot plate-, acetic acid-induced writhing-, and naloxone-precipitated withdrawal jumping-tests. The antinociceptive action of tizanidine was not altered by naloxone, while that of morphine was antagonized. Tolerance to the tizanidine-induced antinociceptive action and to motor incoordination was developed by successive administration of tizanidine. In the tizanidine-tolerant mice, the antinociceptive action of morphine was significantly decreased, but not sleeping time induced by pentobarbital. The action of tizanidine was not modified in the morphine-tolerant mice. Tizanidine failed to induce morphine-withdrawal jumping and to inhibit naloxone-precipitated withdrawal jumping in the morphine-dependent mice. Cross tolerance to the antinociceptive action induced by tizanidine and clonidine was developed. These results suggest that alpha 2-adrenoreceptors may be involved in the action mechanism of tizanidine, but not opioid receptors. Functional tolerance to tizanidine action may be developed by successive administration of tizanidine.

Fatty acid amide hydrolase-morphine interaction influences ventilatory response to hypercapnia and postoperative opioid outcomes in children.

PubMed

Chidambaran, Vidya; Pilipenko, Valentina; Spruance, Kristie; Venkatasubramanian, Raja; Niu, Jing; Fukuda, Tsuyoshi; Mizuno, Tomoyuki; Zhang, Kejian; Kaufman, Kenneth; Vinks, Alexander A; Martin, Lisa J; Sadhasivam, Senthilkumar

2017-01-01

Fatty acid amide hydrolase (FAAH) degrades anandamide, an endogenous cannabinoid. We hypothesized that FAAH variants will predict risk of morphine-related adverse outcomes due to opioid-endocannabinoid interactions. In 101 postsurgical adolescents receiving morphine analgesia, we prospectively studied ventilatory response to 5% CO 2 (HCVR), respiratory depression (RD) and vomiting. Blood was collected for genotyping and morphine pharmacokinetics. We found significant FAAH-morphine interaction for missense (rs324420) and several regulatory variants, with HCVR (p < 0.0001) and vomiting (p = 0.0339). HCVR was more depressed in patients who developed RD compared with those who did not (p = 0.0034), thus FAAH-HCVR association predicts risk of impending RD from morphine use. FAAH genotypes predict risk for morphine-related adverse outcomes.

A physiologically based model for tramadol pharmacokinetics in horses.

PubMed

Abbiati, Roberto Andrea; Cagnardi, Petra; Ravasio, Giuliano; Villa, Roberto; Manca, Davide

2017-09-21

This work proposes an application of a minimal complexity physiologically based pharmacokinetic model to predict tramadol concentration vs time profiles in horses. Tramadol is an opioid analgesic also used for veterinary treatments. Researchers and medical doctors can profit from the application of mathematical models as supporting tools to optimize the pharmacological treatment of animal species. The proposed model is based on physiology but adopts the minimal compartmental architecture necessary to describe the experimental data. The model features a system of ordinary differential equations, where most of the model parameters are either assigned or individualized for a given horse, using literature data and correlations. Conversely, residual parameters, whose value is unknown, are regressed exploiting experimental data. The model proved capable of simulating pharmacokinetic profiles with accuracy. In addition, it provides further insights on un-observable tramadol data, as for instance tramadol concentration in the liver or hepatic metabolism and renal excretion extent. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative metabolism of tramadol and tapentadol: a toxicological perspective.

PubMed

Barbosa, Joana; Faria, Juliana; Queirós, Odília; Moreira, Roxana; Carvalho, Félix; Dinis-Oliveira, Ricardo Jorge

2016-11-01

Tramadol and tapentadol are centrally acting, synthetic opioid analgesics used in the treatment of moderate to severe pain. Main metabolic patterns for these drugs in humans are well characterized. Tramadol is mainly metabolized by cytochrome P450 CYP2D6 to O-desmethyltramadol (M1), its main active metabolite. M1 and tapentadol undergo mainly glucuronidation reactions. On the other hand, the pharmacokinetics of tramadol and tapentadol are dependent on multiple factors, such as the route of administration, genetic variability in pharmacokinetic components and concurrent consumption of other drugs. This review aims to comparatively discuss the metabolomics of tramadol and tapentadol, namely by presenting all their known metabolites. An exhaustive literature search was performed using textual and structural queries for tramadol and tapentadol, and associated known metabolizing enzymes and metabolites. A thorough knowledge about tramadol and tapentadol metabolomics is expected to provide additional insights to better understand the interindividual variability in their pharmacokinetics and dose-responsiveness, and contribute to the establishment of personalized therapeutic approaches, minimizing side effects and optimizing analgesic efficacy.

Disruption of the CRF(2) receptor pathway decreases the somatic expression of opiate withdrawal.

PubMed

Papaleo, Francesco; Ghozland, Sandy; Ingallinesi, Manuela; Roberts, Amanda J; Koob, George F; Contarino, Angelo

2008-11-01

Escape from the extremely aversive opiate withdrawal symptoms powerfully motivates compulsive drug-seeking and drug-taking behaviors. The corticotropin-releasing factor (CRF) system is hypothesized to mediate the motivational properties of drug dependence. CRF signaling is transmitted by two receptor pathways, termed CRF(1) and CRF(2). To investigate the role for the CRF(2) receptor pathway in somatic opiate withdrawal, in the present study we used genetically engineered mice deficient in the CRF(2) receptor (CRF(2)-/-). We employed a novel, clinically relevant mouse model of 'spontaneous' opiate withdrawal as well as a classical opioid receptor antagonist (naloxone)-precipitated opiate withdrawal paradigm. To induce opiate dependence, mice were treated with intermittent escalating morphine doses (20-100 mg/kg, i.p.). We found that 8-128 h after the last opiate injection, CRF(2)-/- mice showed decreased levels of major somatic signs of spontaneous opiate withdrawal, such as paw tremor and wet dog shake, as compared to wild-type mice. Similarly, challenge with naloxone 2 h after the last morphine injection induced lower levels of paw tremor and wet dog shake in CRF(2)-/- mice as compared to wild-type mice. Despite the differences in somatic signs, wild-type and CRF(2)-/- mice displayed similar plasma corticosterone responses to opiate dosing and withdrawal, indicating a marginal role for the hypothalamus-pituitary-adrenal axis in the CRF(2) receptor mediation of opiate withdrawal. Our results unravel a novel role for the CRF(2) receptor pathway in opiate withdrawal. The CRF(2) receptor pathway might be a critical target of therapies aimed at alleviating opiate withdrawal symptoms and reducing relapse to drug intake.

Disruption of the CRF2 Receptor Pathway Decreases the Somatic Expression of Opiate Withdrawal

PubMed Central

Papaleo, Francesco; Ghozland, Sandy; Ingallinesi, Manuela; Roberts, Amanda J; Koob, George F; Contarino, Angelo

2009-01-01

Escape from the extremely aversive opiate withdrawal symptoms powerfully motivates compulsive drug-seeking and drug-taking behaviors. The corticotropin-releasing factor (CRF) system is hypothesized to mediate the motivational properties of drug dependence. CRF signaling is transmitted by two receptor pathways, termed CRF1 and CRF2. To investigate the role for the CRF2 receptor pathway in somatic opiate withdrawal, in the present study we used genetically engineered mice deficient in the CRF2 receptor (CRF2−/−). We employed a novel, clinically relevant mouse model of ‘spontaneous’ opiate withdrawal as well as a classical opioid receptor antagonist (naloxone)-precipitated opiate withdrawal paradigm. To induce opiate dependence, mice were treated with intermittent escalating morphine doses (20–100 mg/kg, i.p.). We found that 8–128 h after the last opiate injection, CRF2−/− mice showed decreased levels of major somatic signs of spontaneous opiate withdrawal, such as paw tremor and wet dog shake, as compared to wild-type mice. Similarly, challenge with naloxone 2 h after the last morphine injection induced lower levels of paw tremor and wet dog shake in CRF2−/− mice as compared to wild-type mice. Despite the differences in somatic signs, wild-type and CRF2−/− mice displayed similar plasma corticosterone responses to opiate dosing and withdrawal, indicating a marginal role for the hypothalamus–pituitary–adrenal axis in the CRF2 receptor mediation of opiate withdrawal. Our results unravel a novel role for the CRF2 receptor pathway in opiate withdrawal. The CRF2 receptor pathway might be a critical target of therapies aimed at alleviating opiate withdrawal symptoms and reducing relapse to drug intake. PMID:18288089

Analysis of inflammation-induced depression of home cage wheel running in rats reveals the difference between opioid antinociception and restoration of function.

PubMed

Kandasamy, Ram; Calsbeek, Jonas J; Morgan, Michael M

2017-01-15

Opioids are effective at inhibiting responses to noxious stimuli in rodents, but have limited efficacy and many side effects in chronic pain patients. One reason for this disconnect is that nociception is typically assessed using withdrawal from noxious stimuli in animals, whereas chronic pain patients suffer from abnormal pain that disrupts normal activity. We hypothesized that assessment of home cage wheel running in rats would provide a much more clinically relevant method to assess opioid efficacy to restore normal behavior. Intraplantar injection of Complete Freund's Adjuvant (CFA) into the right hindpaw depressed wheel running and caused mechanical allodynia measured with the von Frey test in both male and female rats. Administration of an ED 50 dose of morphine (3.2mg/kg) reversed mechanical allodynia, but did not reverse CFA-induced depression of wheel running. In contrast, administration of a low dose of morphine (1.0mg/kg) restored running for one hour in both sexes, but had no effect on mechanical allodynia. Administration of the atypical opioid buprenorphine had no effect on inflammation-induced depression of wheel running in male or female rats, but attenuated mechanical allodynia in male rats. Administration of buprenorphine and higher doses of morphine depressed wheel running in non-inflamed rats, suggesting that the side effects of opioids interfere with restoration of function. These data indicate that restoration of pain-depressed function requires antinociception in the absence of disruptive side effects. The disruptive side effects of opioids are consistent with the major limitation of opioid use in human pain patients. Copyright © 2016 Elsevier B.V. All rights reserved.

Moderate- vs high-dose methadone in the treatment of opioid dependence: a randomized trial.

PubMed

Strain, E C; Bigelow, G E; Liebson, I A; Stitzer, M L

1999-03-17

Methadone hydrochloride treatment is the most common pharmacological intervention for opioid dependence, and recent interest has focused on expanding methadone treatment availability beyond traditional specially licensed clinics. However, despite recommendations regarding effective dosing of methadone, controlled clinical trials of higher-dose methadone have not been conducted. To compare the relative clinical efficacy of moderate- vs high-dose methadone in the treatment of opioid dependence. A 40-week randomized, double-blind clinical trial starting in June 1992 and ending in October 1995. Outpatient substance abuse treatment research clinic at the Johns Hopkins University Bayview Campus, Baltimore, Md. One hundred ninety-two eligible clinic patients. Daily oral methadone hydrochloride in the dose range of 40 to 50 mg (n = 97) or 80 to 100 mg (n = 95), with concurrent substance abuse counseling. Opioid-positive urinalysis results and retention in treatment. By intent-to-treat analysis through week 30 patients in the high-dose group had significantly lower rates of opioid-positive urine samples compared with patients in the moderate-dose group (53.0% [95% confidence interval [CI], 46.9%-59.2%] vs 61.9% [95% CI, 55.9%-68.0%]; P = .047. These differences persisted during withdrawal from methadone. Through day 210 no significant difference was evident between dose groups in treatment retention (high-dose group mean retention, 159 days; moderate-dose group mean retention, 157 days). Nineteen (33%) of 57 patients in the high-dose group and 11 (20%) of 54 patients in the moderate-dose group completed detoxification. Both moderate- and high-dose methadone treatment resulted in decreased illicit opioid use during methadone maintenance and detoxification. The high-dose group had significantly greater decreases in illicit opioid use.

Alanine analogues of [D-Trp]CJ-15,208: novel opioid activity profiles and prevention of drug- and stress-induced reinstatement of cocaine-seeking behaviour.

PubMed

Aldrich, J V; Senadheera, S N; Ross, N C; Reilley, K A; Ganno, M L; Eans, S E; Murray, T F; McLaughlin, J P

2014-07-01

The novel macrocyclic peptide cyclo[Phe-D-Pro-Phe-D-Trp] ([D-Trp]CJ-15,208) exhibits κ opioid (KOP) receptor antagonist activity in both in vitro and in vivo assays. The four alanine analogues of this peptide were synthesized and characterized both in vitro and in vivo to assess the contribution of different amino acid residues to the activity of [D-Trp]CJ-15,208. The peptides were synthesized by a combination of solid phase peptide synthesis and cyclization in solution. The analogues were evaluated in vitro in receptor binding and functional assays, and in vivo with mice using a tail-withdrawal assay for antinociceptive and opioid antagonist activity. Mice demonstrating extinction of cocaine conditioned-place preference (CPP) were pretreated with selected analogues to evaluate prevention of stress or cocaine-induced reinstatement of CPP. The alanine analogues displayed pharmacological profiles in vivo distinctly different from [D-Trp]CJ-15,208. While the analogues exhibited varying opioid receptor affinities and κ and μ opioid receptor antagonist activity in vitro, they produced potent opioid receptor-mediated antinociception (ED50 = 0.28-4.19 nmol, i.c.v.) in vivo. Three of the analogues also displayed KOP receptor antagonist activity in vivo. Pretreatment with an analogue exhibiting both KOP receptor agonist and antagonist activity in vivo prevented both cocaine- and stress-induced reinstatement of cocaine-seeking behaviour in the CPP assay in a time-dependent manner. These unusual macrocyclic peptides exhibit in vivo opioid activity profiles different from the parent compound and represent novel compounds for potential development as therapeutics for drug abuse and possibly as analgesics. © 2014 The British Pharmacological Society.

Alanine analogues of [D-Trp]CJ-15,208: novel opioid activity profiles and prevention of drug- and stress-induced reinstatement of cocaine-seeking behaviour

PubMed Central

Aldrich, J V; Senadheera, S N; Ross, N C; Reilley, K A; Ganno, M L; Eans, S E; Murray, T F; McLaughlin, J P

2014-01-01

BACKGROUND AND PURPOSE The novel macrocyclic peptide cyclo[Phe-D-Pro-Phe-D-Trp] ([D-Trp]CJ-15,208) exhibits κ opioid (KOP) receptor antagonist activity in both in vitro and in vivo assays. The four alanine analogues of this peptide were synthesized and characterized both in vitro and in vivo to assess the contribution of different amino acid residues to the activity of [D-Trp]CJ-15,208. EXPERIMENTAL APPROACH The peptides were synthesized by a combination of solid phase peptide synthesis and cyclization in solution. The analogues were evaluated in vitro in receptor binding and functional assays, and in vivo with mice using a tail-withdrawal assay for antinociceptive and opioid antagonist activity. Mice demonstrating extinction of cocaine conditioned-place preference (CPP) were pretreated with selected analogues to evaluate prevention of stress or cocaine-induced reinstatement of CPP. KEY RESULTS The alanine analogues displayed pharmacological profiles in vivo distinctly different from [D-Trp]CJ-15,208. While the analogues exhibited varying opioid receptor affinities and κ and μ opioid receptor antagonist activity in vitro, they produced potent opioid receptor-mediated antinociception (ED50 = 0.28–4.19 nmol, i.c.v.) in vivo. Three of the analogues also displayed KOP receptor antagonist activity in vivo. Pretreatment with an analogue exhibiting both KOP receptor agonist and antagonist activity in vivo prevented both cocaine- and stress-induced reinstatement of cocaine-seeking behaviour in the CPP assay in a time-dependent manner. CONCLUSIONS AND IMPLICATIONS These unusual macrocyclic peptides exhibit in vivo opioid activity profiles different from the parent compound and represent novel compounds for potential development as therapeutics for drug abuse and possibly as analgesics. PMID:24588614

Buprenorphine Implants for Treatment of Opioid Dependence: Randomized Comparison to Placebo and Sublingual Buprenorphine/Naloxone

PubMed Central

Rosenthal, Richard N.; Ling, Walter; Casadonte, Paul; Vocci, Frank; Bailey, Genie L.; Kampman, Kyle; Patkar, Ashwin; Chavoustie, Steven; Blasey, Christine; Sigmon, Stacey; Beebe, Katherine L.

2015-01-01

Aims To evaluate safety and efficacy of buprenorphine implants (BI) versus placebo implants (PI) for the treatment of opioid dependence. A secondary aim compared BI to open-label sublingual buprenorphine/naloxone tablets (BNX). Design Randomized, double-blind, placebo-controlled trial. Subjects received either 4 buprenorphine implants (80 mg/implant) (n=114), 4 placebo implants (n=54), or open-label BNX (12–16 mg/d) (n=119). Setting 20 addiction treatment centers. Participants Adult outpatients (ages 18 to 65) with DSM-IV-TR opioid dependence. Measurements The primary efficacy endpoint was the percent of urine samples negative for opioids collected from weeks 1 to 24, examined as a cumulative distribution function (CDF). Findings The BI CDF was significantly different from placebo (P<.0001). Mean (95% CI) proportions of urines negative for opioids were: BI: 31.2% (25.3, 37.1) and PI: 13.4% (8.3, 18.6). BI subjects had a higher study completion rate relative to placebo (64% vs. 26%, P<.0001), lower clinician-rated (P<.0001) and patient-rated (P<.0001) withdrawal, lower patient-ratings of craving (P<.0001), and better subjects’ (P=.031) and clinicians’ (P=.022) global ratings of improvement. BI also resulted in significantly lower cocaine use (P=.0016). Minor implant-site reactions were comparable in the buprenorphine (27.2% [31/114]) and placebo groups (25.9% [14/54]). BI were non-inferior to BNX on percent urines negative for opioids [mean (95% CI): 33.5 (27.3, 39.6); CI for the difference of proportions, (−10.7, 6.2)]. Conclusions Compared with placebo, buprenorphine implants result in significantly less frequent opioid use, and are non-inferior to sublingual buprenorphine/naloxone tablets. PMID:23919595

Buprenorphine implants for treatment of opioid dependence: randomized comparison to placebo and sublingual buprenorphine/naloxone.

PubMed

Rosenthal, Richard N; Ling, Walter; Casadonte, Paul; Vocci, Frank; Bailey, Genie L; Kampman, Kyle; Patkar, Ashwin; Chavoustie, Steven; Blasey, Christine; Sigmon, Stacey; Beebe, Katherine L

2013-12-01

To evaluate the safety and efficacy of buprenorphine implants (BI) versus placebo implants (PI) for the treatment of opioid dependence. A secondary aim compared BI to open-label sublingual buprenorphine/naloxone tablets (BNX). Randomized, double-blind, placebo-controlled trial. Subjects received either four buprenorphine implants (80 mg/implant) (n = 114), four placebo implants (n = 54) or open-label BNX (12-16 mg/day) (n = 119). Twenty addiction treatment centers. Adult out-patients (ages 18-65) with DSM-IV-TR opioid dependence. The primary efficacy end-point was the percentage of urine samples negative for opioids collected from weeks 1 to 24, examined as a cumulative distribution function (CDF). The BI CDF was significantly different from placebo (P < 0.0001). Mean [95% confidence interval (CI)] proportions of urines negative for opioids were: BI = 31.2% (25.3, 37.1) and PI = 13.4% (8.3, 18.6). BI subjects had a higher study completion rate relative to placebo (64 versus 26%, P < 0.0001), lower clinician-rated (P < 0.0001) and patient-rated (P < 0.0001) withdrawal, lower patient-ratings of craving (P < 0.0001) and better subjects' (P = 0.031) and clinicians' (P = 0.022) global ratings of improvement. BI also resulted in significantly lower cocaine use (P = 0.0016). Minor implant-site reactions were comparable in the buprenorphine [27.2% (31 of 114)] and placebo groups [25.9% (14 of 54)]. BI were non-inferior to BNX on percentage of urines negative for opioids [mean (95% CI) = 33.5 (27.3, 39.6); 95% CI for the difference of proportions = (-10.7, 6.2)]. Compared with placebo, buprenorphine implants result in significantly less frequent opioid use and are non-inferior to sublingual buprenorphine/naloxone tablets. © 2013 Society for the Study of Addiction.

Analysis of inflammation-induced depression of home cage wheel running in rats reveals the difference between opioid antinociception and restoration of function

PubMed Central

Kandasamy, Ram; Calsbeek, Jonas J.; Morgan, Michael M.

2016-01-01

Opioids are effective at inhibiting responses to noxious stimuli in rodents, but have limited efficacy and many side effects in chronic pain patients. One reason for this disconnect is that nociception is typically assessed using withdrawal from noxious stimuli in animals, whereas chronic pain patients suffer from abnormal pain that disrupts normal activity. We hypothesized that assessment of home cage wheel running in rats would provide a much more clinically relevant method to assess opioid efficacy to restore normal behavior. Intraplantar injection of Complete Freund’s Adjuvant (CFA) into the right hindpaw depressed wheel running and caused mechanical allodynia measured with the von Frey test in both male and female rats. Administration of an ED50 dose of morphine (3.2 mg/kg) reversed mechanical allodynia, but did not reverse CFA-induced depression of wheel running. In contrast, administration of a low dose of morphine (1.0 mg/kg) restored running for one hour in both sexes, but had no effect on mechanical allodynia. Administration of the atypical opioid buprenorphine had no effect on inflammation-induced depression of wheel running in male or female rats, but attenuated mechanical allodynia in male rats. Administration of buprenorphine and higher doses of morphine depressed wheel running in non-inflamed rats, suggesting that the side effects of opioids interfere with restoration of function. These data indicate that restoration of pain-depressed function requires antinociception in the absence of disruptive side effects. The disruptive side effects of opioids are consistent with the major limitation of opioid use in human pain patients. PMID:27746208

Implementation of an opioid detoxification management pathway reduces emergency department length of stay.

PubMed

Bellew, Shawna D; Collins, Sean P; Barrett, Tyler W; Russ, Stephan E; Jones, Ian D; Slovis, Corey M; Self, Wesley H

2018-05-25

With the rise of opioid use in the United States, the increasing demand for treatment for opioid use disorders presents both a challenge and an opportunity to develop new care pathways for ED patients seeking opioid detoxification. We set out to improve the care of patients presenting to our ED seeking opioid detoxification by implementing a standardized management pathway and to measure the effects of this intervention. We conducted a before-after study of the effects of an opioid detoxification management pathway on ED length of stay, use of resources (social worker consultation, laboratory tests obtained), and return visits to the same ED within 30 days of discharge. All data were collected retrospectively by review of the electronic health record. Ultimately, 107 patients presented to the ED that met criteria, 52 in the intervention period and 55 in the pre-intervention period. Median ED length of stay in the intervention period was 152 (IQR 93-237) minutes compared to 312 (IQR 187-468) minutes in the pre-intervention period (p<0.001). Patients in the intervention period less frequently had a social work consultation (32.7% vs. 83.6%, p<0.001) or had laboratory tests obtained (32.7% vs 74.5%, p<0.001) and more frequently were prescribed a medication for withdrawal symptoms (57.7% vs. 29.1%, p=0.003). Implementation of an opioid detoxification management pathway reduced ED length of stay, reduced utilization of resources, and increased the proportion of patients prescribed medications for symptom relief. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Will abuse-deterrent formulations of opioid analgesics be successful in achieving their purpose?

PubMed

Bannwarth, Bernard

2012-09-10

During the last 2 decades, there has been a dramatic increase in the use of strong opioids for chronic non-cancer pain. This increase has been accompanied by a steep increase in abuse, misuse, and both fatal and non-fatal overdoses involving prescription opioids. The situation is already alarming in the US. Prescription opioid-related harm is a complex, multifactorial issue that requires a multifaceted solution. In this respect, formulations of opioid analgesics designed to resist or deter abuse may be a useful component of a comprehensive opioid risk minimization programme. Such formulations have or are being developed. Abuse-resistant opioids include those that use some kind of physical barrier to prevent tampering with the formulation. Abuse-deterrent opioids are not necessarily resistant to tampering, but contain substances that are designed to make the formulation less attractive to abusers. This article focuses on two products intended to deter abuse that were reviewed by the US Food and Drug Administration (FDA). The first (Embeda®) consists of extended-release morphine with sequestered naltrexone, an opioid antagonist that is released if the tablet is compromised by chewing or crushing. Although Embeda® exhibited abuse-deterrent features, its label warns that it can be abused in a manner similar to other opioid agonists. Furthermore, tampering with Embeda® will result in the release of naltrexone, which may precipitate withdrawal in opioid-tolerant individuals. In March 2011, all dosage forms of Embeda® were recalled because the product failed to meet routine stability standards, and its return date to the market is currently unknown. The second product (Acurox®) was intended to be both tamper resistant and abuse deterrent. It consisted of an immediate-release oxycodone tablet with subtherapeutic niacin as an aversive agent and used a gel-forming ingredient designed to inhibit inhalation and prevent extraction of the drug for injection. The new drug application for Acurox® was rejected in 2010 by the FDA because of concerns about the potential abuse-deterrent benefits of niacin. While acknowledging that no one formulation can be expected to deter all types of opioid-abusive behaviours and no product is likely to be abuse proof in the hands of clear and determined abusers, the reductions in abuse these new products would provide may be an incremental step towards safer prescription opioids.

Opioid-use disorder among patients on long-term opioid therapy: impact of final DSM-5 diagnostic criteria on prevalence and correlates.

PubMed

Boscarino, Joseph A; Hoffman, Stuart N; Han, John J

2015-01-01

Previously, we estimated the prevalence and risk factors for prescription opioid-use disorder among outpatients on opioid therapy using the Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 and DSM-4 criteria. However, at the time, the DSM-5 criteria were not finalized. In the current study, we analyzed these data using the final DSM-5 criteria and compared these results. Using electronic records from a large US health care system, we identified outpatients receiving five or more prescription orders for opioid therapy in the past 12 months for noncancer pain (mean prescription orders =10.72; standard deviation =4.96). In 2008, we completed diagnostic interviews with 705 of these patients using the DSM-4 criteria. In the current study, we reassessed these results using the final DSM-5 criteria. The lifetime prevalence of DSM-5 opioid-use disorders using the final DSM-5 criteria was 58.7% for no or few symptoms (<2), 28.1% for mild symptoms (2-3), 9.7% for moderate symptoms (4-5), and 3.5% for severe symptoms (six or more). Thus, the lifetime prevalence of "any" prescription opioid-use disorder in this cohort was 41.3% (95% confidence interval [CI] =37.6-45.0). A comparison to the DSM-4 criteria indicated that the majority of patients with lifetime DSM-4 opioid dependence were now classified as having mild opioid-use disorder, based on the DSM-5 criteria (53.6%; 95% CI =44.1-62.8). In ordinal logistic regression predicting no/few, mild, moderate, and severe opioid-use disorder, the best predictors were age <65 years, current pain impairment, trouble sleeping, suicidal thoughts, anxiety disorders, illicit drug use, and history of substance abuse treatment. Given the final DSM-5 criteria, including the elimination of tolerance and withdrawal, inclusion of craving and abuse symptoms, and introduction of a new graded severity classification, the prevalence of opioid-use disorders has changed, while many of the DSM-4 risk factors for opioid dependence were similar. To our knowledge, this is one of the first studies to compare the final results for DSM-5 versus DSM-4 prescription opioid-use disorders among a high-risk patient population.

Opioid-use disorder among patients on long-term opioid therapy: impact of final DSM-5 diagnostic criteria on prevalence and correlates

PubMed Central

Boscarino, Joseph A; Hoffman, Stuart N; Han, John J

2015-01-01

Aims Previously, we estimated the prevalence and risk factors for prescription opioid-use disorder among outpatients on opioid therapy using the Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 and DSM-4 criteria. However, at the time, the DSM-5 criteria were not finalized. In the current study, we analyzed these data using the final DSM-5 criteria and compared these results. Methods Using electronic records from a large US health care system, we identified outpatients receiving five or more prescription orders for opioid therapy in the past 12 months for noncancer pain (mean prescription orders =10.72; standard deviation =4.96). In 2008, we completed diagnostic interviews with 705 of these patients using the DSM-4 criteria. In the current study, we reassessed these results using the final DSM-5 criteria. Results The lifetime prevalence of DSM-5 opioid-use disorders using the final DSM-5 criteria was 58.7% for no or few symptoms (<2), 28.1% for mild symptoms (2–3), 9.7% for moderate symptoms (4–5), and 3.5% for severe symptoms (six or more). Thus, the lifetime prevalence of “any” prescription opioid-use disorder in this cohort was 41.3% (95% confidence interval [CI] =37.6–45.0). A comparison to the DSM-4 criteria indicated that the majority of patients with lifetime DSM-4 opioid dependence were now classified as having mild opioid-use disorder, based on the DSM-5 criteria (53.6%; 95% CI =44.1–62.8). In ordinal logistic regression predicting no/few, mild, moderate, and severe opioid-use disorder, the best predictors were age <65 years, current pain impairment, trouble sleeping, suicidal thoughts, anxiety disorders, illicit drug use, and history of substance abuse treatment. Conclusion Given the final DSM-5 criteria, including the elimination of tolerance and withdrawal, inclusion of craving and abuse symptoms, and introduction of a new graded severity classification, the prevalence of opioid-use disorders has changed, while many of the DSM-4 risk factors for opioid dependence were similar. To our knowledge, this is one of the first studies to compare the final results for DSM-5 versus DSM-4 prescription opioid-use disorders among a high-risk patient population. PMID:26316838

Abuse potential, pharmacokinetics, pharmacodynamics, and safety of intranasally administered crushed oxycodone HCl abuse-deterrent controlled-release tablets in recreational opioid users

PubMed Central

Harris, Stephen C; Perrino, Peter J; Smith, Ira; Shram, Megan J; Colucci, Salvatore V; Bartlett, Cynthia; Sellers, Edward M

2014-01-01

The objective of this study was to evaluate abuse potential, pharmacokinetics, pharmacodynamics, and safety of intranasally administered, crushed reformulated OxyContin® (oxycodone HCl controlled-release) tablets (ORF), relative to crushed original OxyContin® (OC), oxycodone powder (Oxy API), and OC placebo. This randomized, double-blind, positive- and placebo-controlled crossover study enrolled healthy, adult, nonphysically dependent recreational opioid users with recent history of intranasal drug abuse (N = 27). Active treatments contained oxycodone (30 mg). Pharmacokinetics, pharmacodynamics (e.g., Overall Drug Liking [ODL], Take Drug Again [TDA], and High Visual Analog Scales [VAS]; Subjective Drug Value [SDV]; pupillometry; intranasal irritation), and safety (e.g., adverse events, vital signs, laboratory tests) were assessed to 24 hours postdose. Crushed ORF administration yielded reduced oxycodone Cmax and increased Tmax versus crushed OC and Oxy API. Peak effects for pharmacodynamic measures were delayed with ORF (1–2 hours) versus OC and Oxy API (0.5–1 hour). ODL, TDA, High VAS, and SDV Emax values were significantly lower (P ≤ .05) and some intranasal irritation ratings were greater for ORF versus OC and Oxy API. No significant or unexpected safety findings were observed. Compared with OC and Oxy API, intranasally administered ORF was associated with lower and delayed peak plasma concentrations, decreased drug-liking, and decreased intranasal tolerability. This suggests that ORF has a decreased potential for intranasal oxycodone abuse. There were no significant or unexpected safety findings. As is true for all abuse potential studies, epidemiological or other appropriate post-marketing studies are required to assess the impact of the reduction in intranasal oxycodone abuse potential observed in the present study on real-world patterns of ORF misuse, abuse, and diversion. PMID:24243216

Gonadal Hormone Modulation of Mu, Kappa, and Delta Opioid Antinociception in Male and Female Rats

PubMed Central

Stoffel, Erin C.; Ulibarri, Catherine M.; Folk, John E.; Rice, Kenner C.

2005-01-01

Previous studies suggest that sex differences in morphine antinociception in rodents might be attributed to the activational effects of gonadal hormones. The present study determined whether hormonal modulation of opioid antinociception in adult rats extends to opioids other than the prototypic mu agonist morphine. Male and female rats were sham-gonadectomized (sham-GDX) or gonadectomized (GDX) and replaced with no hormone, estradiol (E2, females), progesterone (P4, females), E2+P4 (females), or testosterone (males). Approximately 28 days later, nociception was evaluated on the 50°C hot plate and warm water tail withdrawal tests before and after subcutaneous administration of hydromorphone, buprenorphine, U50,488, or SNC 80. In sham-GDX (gonadally intact) rats, the mu agonists and U50,488 were less effective in females than in males in at least one nociceptive test, and the delta agonist SNC 80 was less effective in males than in females. In males, gonadectomy tended to decrease, and testosterone tended to increase antinociception produced by 3 of the 4 agonists. In females, gonadectomy and hormone treatment had more variable effects, although E2 tended to decrease mu opioid antinociception. The present results suggest that activational effects of gonadal hormones are relatively modest and somewhat inconsistent on antinociception produced by various opioid agonists in the adult rat. Perspective: This study demonstrates that reproductive hormones such as testosterone in males and estradiol in females do not consistently modulate sensitivity to the analgesic effects of opioids in the adult organism. PMID:15820914

Probuphine® (buprenorphine implant): a promising candidate in opioid dependence

PubMed Central

Barnwal, Preeti; Das, Saibal; Mondal, Somnath; Ramasamy, Anand; Maiti, Tanay; Saha, Arunava

2016-01-01

Opioid dependence leads to physical dependence and addiction which finally results in profound medical, psychological and social dysfunction. One of the useful medications for opioid dependence is buprenorphine, the partial opioid agonist, which is used alone or in combination with naloxone. However, buprenorphine is the victim of its own success due to its illicit use and accidental poisoning in children. Also, buprenorphine typically requires daily self-administration and its effectiveness heavily depends on patient adherence. So, poor treatment adherence results in ineffective treatment manifesting as craving and withdrawal symptoms. Short-term use of buprenorphine in opioid dependence is also often followed by relapse. Buprenorphine when used sublingually often results in inadequate or fluctuating blood concentrations and poorer treatment retention compared with methadone. All of these led to the development of Probuphine®, a polymeric matrix composed of ethylene vinyl acetate and buprenorphine in the form of implants, that are implanted subdermally in office practice and deliver the active drug over 6 months. Buprenorphine release from such implant is fairly consistent, avoiding plasma peaks and troughs, and the implant is also reported to be safe. In this review article, we have highlighted these aspects of treatment of opioid addiction, stressing on the pharmacology of buprenorphine and Probuphine®, and relevant clinical trials addressing the efficacy and safety of Probuphine®. This sustained-release implantable formulation of buprenorphine has the potential to be a suitable alternative to daily or alternate day sublingual buprenorphine which can thereby eliminate the need for daily supervision, minimizing fluctuations in plasma concentrations, and allowing these patients to reduce clinic or pharmacy visits. PMID:28348732

Probuphine® (buprenorphine implant): a promising candidate in opioid dependence.

PubMed

Barnwal, Preeti; Das, Saibal; Mondal, Somnath; Ramasamy, Anand; Maiti, Tanay; Saha, Arunava

2017-03-01

Opioid dependence leads to physical dependence and addiction which finally results in profound medical, psychological and social dysfunction. One of the useful medications for opioid dependence is buprenorphine, the partial opioid agonist, which is used alone or in combination with naloxone. However, buprenorphine is the victim of its own success due to its illicit use and accidental poisoning in children. Also, buprenorphine typically requires daily self-administration and its effectiveness heavily depends on patient adherence. So, poor treatment adherence results in ineffective treatment manifesting as craving and withdrawal symptoms. Short-term use of buprenorphine in opioid dependence is also often followed by relapse. Buprenorphine when used sublingually often results in inadequate or fluctuating blood concentrations and poorer treatment retention compared with methadone. All of these led to the development of Probuphine®, a polymeric matrix composed of ethylene vinyl acetate and buprenorphine in the form of implants, that are implanted subdermally in office practice and deliver the active drug over 6 months. Buprenorphine release from such implant is fairly consistent, avoiding plasma peaks and troughs, and the implant is also reported to be safe. In this review article, we have highlighted these aspects of treatment of opioid addiction, stressing on the pharmacology of buprenorphine and Probuphine®, and relevant clinical trials addressing the efficacy and safety of Probuphine®. This sustained-release implantable formulation of buprenorphine has the potential to be a suitable alternative to daily or alternate day sublingual buprenorphine which can thereby eliminate the need for daily supervision, minimizing fluctuations in plasma concentrations, and allowing these patients to reduce clinic or pharmacy visits.

Dexmedetomidine ameliorates nocifensive behavior in humanized sickle cell mice

PubMed Central

Calhoun, Gabriela; Wang, Li; Almeida, Luis E.F.; Kenyon, Nicholas; Afsar, Nina; Nouraie, Mehdi; Finkel, Julia C.; Quezado, Zenaide M.N.

2015-01-01

Patients with sickle cell disease (SCD) can have recurrent episodes of vaso-occlusive crises, which are associated with severe pain. While opioids are the mainstay of analgesic therapy, in some patients, increasing opioid use results in continued and increasing pain. Many believe that this phenomenon results from opioid-induced tolerance or hyperalgesia or that SCD pain involves non-opioid-responsive mechanisms. Dexmedetomidine, a specific α2-adrenoreceptor agonist, which has sedative and analgesic properties, reduces opioid requirements, and can facilitate opioid withdrawal in clinical settings. We hypothesized that dexmedetomidine would ameliorate the nociception phenotype of SCD mice. Townes and BERK SCD mice, strains known to have altered nociception phenotypes, were used in a crossover preclinical trial that measured nocifensive behavior before and after treatment with dexmedetomidine or vehicle. In a linear dose-effect relationship, over 60-min, dexmedetomidine, compared with vehicle, significantly increased hot plate latency in Townes and BERK mice (P≤0.006). In sickling, but not control mice, dexmedetomidine improved grip force, an indicator of muscle pain (P=0.002). As expected, dexmedetomidine had a sedative effect in sickling and control mice as it decreased wakefulness scores compared with vehicle (all P<0.001). Interestingly, the effects of dexmedetomidine on hot plate latency and wakefulness scores were different in sickling and control mice, i.e., dexmedetomidine-related increases in hotplate latency and decreases in wakefulness scores were significantly smaller in Townes sickling compared to control mice. In conclusion, these findings of beneficial effects of dexmedetomidine on the nociception phenotype in SCD mice might support the conduct of studies of dexmedetomidine in SCD patients. PMID:25724786

Development of a physiologically based pharmacokinetic model for flunixin in cattle (Bos taurus).

PubMed

Leavens, Teresa L; Tell, Lisa A; Kissell, Lindsey W; Smith, Geoffrey W; Smith, David J; Wagner, Sarah A; Shelver, Weilin L; Wu, Huali; Baynes, Ronald E; Riviere, Jim E

2014-01-01

Frequent violation of flunixin residues in tissues from cattle has been attributed to non-compliance with the USFDA-approved route of administration and withdrawal time. However, the effect of administration route and physiological differences among animals on tissue depletion has not been determined. The objective of this work was to develop a physiologically based pharmacokinetic (PBPK) model to predict plasma, liver and milk concentrations of flunixin in cattle following intravenous (i.v.), intramuscular (i.m.) or subcutaneous (s.c.) administration for use as a tool to determine factors that may affect the withdrawal time. The PBPK model included blood flow-limited distribution in all tissues and elimination in the liver, kidney and milk. Regeneration of parent flunixin due to enterohepatic recirculation and hydrolysis of conjugated metabolites was incorporated in the liver compartment. Values for physiological parameters were obtained from the literature, and partition coefficients for all tissues but liver and kidney were derived empirically. Liver and kidney partition coefficients and elimination parameters were estimated for 14 pharmacokinetic studies (including five crossover studies) from the literature or government sources in which flunixin was administered i.v., i.m. or s.c. Model simulations compared well with data for the matrices following all routes of administration. Influential model parameters included those that may be age or disease-dependent, such as clearance and rate of milk production. Based on the model, route of administration would not affect the estimated days to reach the tolerance concentration (0.125 mg kg(-1)) in the liver of treated cattle. The majority of USDA-reported violative residues in liver were below the upper uncertainty predictions based on estimated parameters, which suggests the need to consider variability due to disease and age in establishing withdrawal intervals for drugs used in food animals. The model predicted that extravascular routes of administration prolonged flunixin concentrations in milk, which could result in violative milk residues in treated cattle.

Pregabalin role in inhibition of morphine analgesic tolerance and physical dependency in rats.

PubMed

Hasanein, Parisa; Shakeri, Saeed

2014-11-05

Pregabalin is recently proposed as analgesic or adjuvant in pain management. While previous preclinical investigations have evaluated pregabalin-opioid interactions, the effect of pregabalin on opioid tolerance and dependency has not yet been studied. Here we evaluated the effects of different doses of pregabalin (50, 100 and 200mg/kg, s.c.) on morphine-induced tolerance and dependency in rats. Adult male Wistar rats were rendered tolerant to analgesic effect of morphine by injection of morphine (10mg/kg, s.c.) twice daily for 7 days. To develop morphine dependence, rats were given escalating doses of morphine. To determine the effect of pregabalin on the development of morphine tolerance and dependence, different doses of pregabalin were administrated before morphine. The tail-flick and naloxone precipitation withdrawal tests were used to evaluate the degree of tolerance and dependence, respectively. Chronic morphine-injected rats showed significant decrements in the percentage maximum possible effect (%MPE) of morphine on the days 5 and 7 (32.5%±3.5, 21.5%±4, respectively) compared to the first day (100%) which showed morphine tolerance. Pregabalin 200mg/kg completely prevented the development of morphine tolerance. In addition, concomitant treatment of morphine with pregabalin attenuated almost all of the naloxone-induced withdrawal signs which include weight loss, jumping, penis licking, teeth chattering, wet dog shakes, rearing, standing, sniffing, face grooming and paw tremor. These data show that pregabaline has a potential anti-tolerant/anti-dependence property against chronic usage of morphine. Therefore, pregabalin appears to be a promising candidate for the treatment of opioid addiction after confirming by future clinical studies. Copyright © 2014 Elsevier B.V. All rights reserved.

Slow-release oral morphine for opioid maintenance treatment: a systematic review

PubMed Central

Jegu, Jeremie; Gallini, Adeline; Soler, Pauline; Montastruc, Jean-Louis; Lapeyre-Mestre, Maryse

2011-01-01

This review article summarizes the results of all available clinical trials considering the use of slow-release oral morphine (SROM) for opioid maintenance treatment (OMT). All studies published up to October 2010 and assessing SROM for OMT in adult patients are included. Three independent reviewers assessed the selected articles using a standardized checklist. Study design, study length and number of subjects included were recorded. Data about retention rate (proportion of participants remaining under maintenance treatment at the end of the study), quality of life, withdrawal symptoms, craving, additional drug consumption, driving capacity and adverse events were collected. We identified 13 articles corresponding to nine clinical trials considering the use of SROM for OMT. Among them, only one was a randomized trial and one was a controlled not randomized trial. All other studies were uncontrolled. Retention rates were good (from 80.6 to 95%) with SROM maintenance, but similar retention rates were obtained with methadone. Most of the studies showed that quality of life, withdrawal symptoms, craving and additional drug consumption improved with SROM. However, there was no comparison with other maintenance drugs. As most of the studies assessing SROM efficacy were uncontrolled, there is no definite evidence that SROM is an effective alternative to methadone for OMT. PMID:21265874

Superior analgesic effect of H-Dmt-D-Arg-Phe-Lys-NH2 ([Dmt1]DALDA), a multifunctional opioid peptide, compared to morphine in a rat model of neuropathic pain.

PubMed

Shimoyama, Megumi; Schiller, Peter W; Shimoyama, Naohito; Toyama, Satoshi; Szeto, Hazel H

2012-11-01

H-Dmt-D-Arg-Phe-Lys-NH(2) ([Dmt(1)]DALDA) is a synthetic tetrapeptide with extraordinary selectivity for the mu-opioid receptor and is an extremely potent analgesic. [Dmt(1) ]DALDA is unusual in the way that the greater part of its analgesic potency appears to be produced by its actions in the spinal cord. Furthermore, [Dmt(1) ]DALDA inhibits norepinephrine re-uptake and is a mitochondria-targeted antioxidant. Such characteristics may make [Dmt(1)]DALDA particularly effective against neuropathic pain. The present study was designed to compare the effects of [Dmt(1)]DALDA and morphine on thermal hyperalgesia in an experimental neuropathic pain model. Neuropathic pain was induced in rats by surgical ligation of the L5 spinal nerve, and thermal pain thresholds were assessed by latencies of paw withdrawal to radiant heat. The increase in paw withdrawal latency was greater after the administration of [Dmt(1) ]DALDA than that of morphine in neuropathic rats at doses that were equianalgesic in naïve animals. We conclude that [Dmt(1)]DALDA is more effective than morphine against thermal hyperalgesia in this experimental model of neuropathic pain. © 2012 John Wiley & Sons A/S.

Drug Discontinuation Effects Are Part of the Pharmacology of a Drug

PubMed Central

2011-01-01

Most reviews of drug withdrawal effects focus on drugs of potential abuse such as opioids, benzodiazepines, etc. Abrupt discontinuation of many other drugs used in medicine cause withdrawal syndromes, some of which can be fatal. Discontinuation of a number of cardiovascular drugs can increase risk of cardiovascular events above that of people not taking these drugs. These include β-adrenergic receptor antagonists, aspirin, HMG-CoA reductase inhibitors (statins), and heparin. Rebound hypertension occurs after abrupt cessation of many antihypertensive drugs. The possibility of discontinuation syndromes has usually been neglected until adverse clinical events force them to be noticed. Attention to the possibility of drug discontinuation effects is an important part of drug safety evaluation. PMID:21849624

No Clinically Relevant Drug-Drug Interactions between Methadone or Buprenorphine-Naloxone and Antiviral Combination Glecaprevir and Pibrentasvir

PubMed Central

Kosloski, Matthew P.; Zhao, Weihan; Asatryan, Armen; Kort, Jens; Geoffroy, Pierre

2017-01-01

ABSTRACT The combination of glecaprevir (formerly ABT-493), a nonstructural protein 3/4A (NS3/4A) protease inhibitor, and pibrentasvir (formerly ABT-530), an NS5A protein inhibitor, is being developed as treatment for HCV genotype 1 to 6 infection. The pharmacokinetics, pharmacodynamics, safety, and tolerability of methadone or buprenorphine-naloxone when coadministered with the glecaprevir-pibrentasvir combination in HCV-negative subjects on stable opioid maintenance therapy were investigated in a phase 1, single-center, two-arm, multiple-dose, open-label sequential study. Subjects received methadone (arm 1) or buprenorphine-naloxone (arm 2) once daily (QD) per their existing individual prescriptions alone (days 1 to 9) and then in combination with glecaprevir at 300 mg QD and pibrentasvir at 120 mg QD (days 10 to 16) each morning. Dose-normalized exposures were similar with and without glecaprevir and pibrentasvir for (R)- and (S)-methadone (≤5% difference) and for buprenorphine and naloxone (≤24% difference); the norbuprenorphine area under the curve was 30% higher with glecaprevir and pibrentasvir, consistent with maximum and trough plasma concentrations that increased by 21% to 25%. No changes in pupil response, short opiate withdrawal scale score, or desire for drugs questionnaire were observed when glecaprevir and pibrentasvir were added to methadone or buprenorphine-naloxone therapy. No dose adjustment is required when glecaprevir and pibrentasvir are coadministered with methadone or buprenorphine-naloxone. PMID:28807904

Efficacy and Safety of Oral and Transdermal Opioid Analgesics for Musculoskeletal Pain in Older Adults: A Systematic Review of Randomized, Placebo-Controlled Trials.

PubMed

Megale, Rodrigo Z; Deveza, Leticia A; Blyth, Fiona M; Naganathan, Vasi; Ferreira, Paulo H; McLachlan, Andrew J; Ferreira, Manuela L

2018-05-01

This systematic review with meta-analysis was performed to evaluate the efficacy and safety of using opioid analgesics in older adults with musculoskeletal pain. We searched Cochrane Library, MEDLINE, EMBASE, Web of Science, AMED, CINAHL, and LILACS for randomized controlled trials with mean population age of 60 years or older, comparing the efficacy and safety of opioid analgesics with placebo for musculoskeletal pain conditions. Reviewers extracted data, assessed risk of bias, and evaluated the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation approach. Random effects models were used to calculate standardized mean differences (when different scales were used across trials), mean differences and odds ratios with respective 95% confidence intervals (CIs). Meta-regressions were carried out to assess the influence of opioid analgesic daily dose and treatment duration on our main outcomes. We included 23 randomized placebo-controlled trials in the meta-analysis. Opioid analgesics had a small effect on decreasing pain intensity (standardized mean difference = -.27; 95% CI = -.33 to -.20) and improving function (standardized mean difference = -.27, 95% CI = -.36 to -.18), which was not associated with daily dose or treatment duration. The odds of adverse events were 3 times higher (odds ratio = 2.94; 95% CI = 2.33-3.72) and the odds of treatment discontinuation due to adverse events 4 times higher (odds ratio = 4.04; 95% CI = 3.10-5.25) in patients treated with opioid analgesics. The results show that in older adults suffering from musculoskeletal pain, using opioid analgesics had only a small effect on pain and function at the cost of a higher odds of adverse events and treatment discontinuation. For this specific population, the opioid-related risks may outweigh the benefits. The systematic review shows that, in older adults suffering from musculoskeletal conditions, opioid analgesics have only a small effect on pain and disability. Conversely, this population is at higher risk of adverse events. The results may reflect age-related physiological changes in pain processing, pharmacokinetics, and pharmacodynamics. Copyright © 2017 The American Pain Society. Published by Elsevier Inc. All rights reserved.

Combined administration of buprenorphine and naltrexone produces antidepressant-like effects in mice

PubMed Central

Almatroudi, Abdulrahman; Husbands, Stephen M.; Bailey, Christopher P.; Bailey, Sarah J.

2016-01-01

Opiates have been used historically for the treatment of depression. Renewed interest in the use of opiates as antidepressants has focussed on the development of kappa opioid receptor (κ-receptor) antagonists. Buprenorphine acts as a partial μ-opioid receptor agonist and a κ-receptor antagonist. By combining buprenorphine with the opioid antagonist naltrexone, the activation of μ-opioid receptors would be reduced and the κ-antagonist properties enhanced. We have established that a combination dose of buprenorphine (1mg/kg) with naltrexone (1mg/kg) functions as a short-acting κ-antagonist in the mouse tail withdrawal test. Furthermore, this dose combination is neither rewarding nor aversive in the conditioned place preference paradigm and is without significant locomotor effects. We have shown for the first time that systemic co-administration of buprenorphine (1mg/kg) with naltrexone (1mg/kg) in CD-1 mice produced significant antidepressant-like responses in behaviours in both the forced swim test and novelty induced hypophagia task. Behaviours in the elevated plus maze and light dark box were not significantly altered by treatment with buprenorphine alone, or in combination with naltrexone. We propose that the combination of buprenorphine with naltrexone represents a novel, and potentially a readily translatable approach, to the treatment of depression. PMID:26045511

Comparison of pharmacokinetics and milk elimination of flunixin in healthy cows and cows with mastitis.

PubMed

Kissell, Lindsey W; Leavens, Teresa L; Baynes, Ronald E; Riviere, Jim E; Smith, Geof W

2015-01-01

To determine whether pharmacokinetics and milk elimination of flunixin and 5-hydroxy flunixin differed between healthy and mastitic cows. Prospective controlled clinical trial. 20 lactating Holstein cows. Cows with mastitis and matched control cows received flunixin IV, ceftiofur IM, and cephapirin or ceftiofur, intramammary. Blood samples were collected before (time 0) and 0.25, 0.5, 1, 2, 4, 8, 12, 24, and 36 hours after flunixin administration. Composite milk samples were collected at 0, 2, 12, 24, 36, 48, 60, 72, 84, and 96 hours. Plasma and milk samples were analyzed by use of ultra-high-performance liquid chromatography with mass spectrometric detection. For flunixin in plasma samples, differences in area under the concentration-time curve and clearance were detected between groups. Differences in flunixin and 5-hydroxy flunixin concentrations in milk were detected at various time points. At 36 hours after flunixin administration (milk withdrawal time), 8 cows with mastitis had 5-hydroxy flunixin concentrations higher than the tolerance limit (ie, residues). Flunixin residues persisted in milk up to 60 hours after administration in 3 of 10 mastitic cows. Pharmacokinetics and elimination of flunixin and 5-hydroxy flunixin in milk differed between mastitic and healthy cows, resulting in violative residues. This may partially explain the high number of flunixin residues reported in beef and dairy cattle. This study also raised questions as to whether healthy animals should be used when determining withdrawal times for meat and milk.

Pharmacokinetics of guaifenesin following administration of multiple doses to exercised Thoroughbred horses.

PubMed

Knych, H K; Stanley, S D; Benson, D; Arthur, R M

2016-08-01

Guaifenesin is an expectorant commonly used in performance horses to aid in the clearance of mucus from the airways. Guaifenesin is also a centrally acting skeletal muscle relaxant and as such is a prohibited drug with withdrawal necessary prior to competition. To the authors' knowledge, there are no reports in the literature describing single or multiple oral administrations of guaifenesin in the horse to determine a regulatory threshold and related withdrawal time. Therefore, the objective of the current study was to describe the pharmacokinetics of guaifenesin following oral administration in order to provide data upon which appropriate regulatory recommendations can be established. Nine exercised Thoroughbred horses were administered 2 g of guaifenesin orally BID for a total of five doses. Blood samples were collected immediately prior to drug administration and at various times postadministration. Serum guaifenesin concentrations were determined and pharmacokinetic parameters calculated. Guaifenesin was rapidly absorbed (Tmax of 15 min) following oral administration. The Cmax was 681.3 ± 323.8 ng/mL and 1080 ± 732.8 following the first and last dose, respectively. The serum elimination half-life was 2.62 ± 1.24 h. Average serum guaifenesin concentrations remained above the LOQ of the assay (0.5 ng/mL) by 48 h postadministration of the final dose in 3 of 9 horses. © 2016 John Wiley & Sons Ltd.

Methadone, Buprenorphine and Preferences for Opioid Agonist Treatment: A Qualitative Analysis

PubMed Central

Yarborough, Bobbi Jo H.; Stumbo, Scott P.; McCarty, Dennis; Mertens, Jennifer; Weisner, Constance; Green, Carla A.

2016-01-01

Background Patients and clinicians have begun to recognize the advantages and disadvantages of buprenorphine relative to methadone, but factors that influence choices between these two medications remain unclear. For example, we know little about how patients’ preferences and previous experiences influence treatment decisions. Understanding these issues may enhance treatment engagement and retention. Methods Adults with opioid dependence (n = 283) were recruited from two integrated health systems to participate in interviews focused on prior experiences with treatment for opioid dependence, knowledge of medication options, preferences for treatment, and experiences with treatment for chronic pain in the context of problems with opioids. Interviews were audio-recorded, transcribed verbatim, and coded using Atlas.ti. Results Our analysis revealed seven areas of consideration for opioid agonist treatment decision-making: 1) awareness of treatment options; 2) expectations and goals for duration of treatment and abstinence; 3) prior experience with buprenorphine or methadone; 4) need for accountability and structured support; 5) preference to avoid methadone clinics or associated stigma; 6) fear of continued addiction and perceived difficulty of withdrawal; and 7) pain control. Conclusion The availability of medication options increases the need for clear communication between clinicians and patients, for additional patient education about these medications, and for collaboration and patient influence over choices in treatment decision-making. Our results suggest that access to both methadone and buprenorphine will increase treatment options and patient choice and may enhance treatment adherence and outcomes. PMID:26796596

Single-molecular diodes based on opioid derivatives.

PubMed

Siqueira, M R S; Corrêa, S M; Gester, R M; Del Nero, J; Neto, A M J C

2015-12-01

We propose an efficient single-molecule rectifier based on a derivative of opioid. Electron transport properties are investigated within the non-equilibrium Green's function formalism combined with density functional theory. The analysis of the current-voltage characteristics indicates obvious diode-like behavior. While heroin presents rectification coefficient R>1, indicating preferential electronic current from electron-donating to electron-withdrawing, 3 and 6-acetylmorphine and morphine exhibit contrary behavior, R<1. Our calculations indicate that the simple inclusion of acetyl groups modulate a range of devices, which varies from simple rectifying to resonant-tunneling diodes. In particular, the rectification rations for heroin diodes show microampere electron current with a maximum of rectification (R=9.1) at very low bias voltage of ∼0.6 V and (R=14.3)∼1.8 V with resistance varying between 0.4 and 1.5 M Ω. Once most of the current single-molecule diodes usually rectifies in nanoampere, are not stable over 1.0 V and present electrical resistance around 10 M. Molecular devices based on opioid derivatives are promising in molecular electronics.

Total intravenous anesthesia as a target-controlled infusion. An evolutive analysis.

PubMed

Nora, Fernando Squeff

2008-01-01

Total intravenous anesthesia (TIVA) has seen several developments since it was first used. Since the synthesis of the first intravenous anesthetics, with the introduction of barbiturates (1921) and thiopental (1934), TIVA has evolved until the development of TIVA with target-controlled infusion pumps (TCI). The first pharmacokinetic model for the use of TCI was described by Schwilden in 1981. From that moment on, it was demonstrated that it is possible to maintain the desired plasma concentration of a drug using an infusion pump managed by a computer. The objective of this report was to describe the theoretical bases of TCI, propose the development of a common TCI vocabulary, which has not been done in Brazil and make a critical analysis of the current aspects of TCI in the world and in Brazil. The advent of new infusion pumps with pharmacokinetic models of remifentanil, sufentanil and propofol opens a new chapter in TIVA and aligns Brazil with the world tendency in TCI. Those systems will allow TCI of hypnotics and opioids concomitantly. However, the most important conclusion refers to the economy, since drugs used in those pumps will not be restricted to only one drug company, similar to what happened with propofol. Nowadays, TCI devices for the use of propofol and opioids, which accept any pharmaceutical presentation, with the advantage of changing the concentration of the drug in the syringe according to the dilution desired are available.

Steady-state pharmacokinetics of (R)- and (S)-methadone in methadone maintenance patients

PubMed Central

Foster, David J R; Somogyi, Andrew A; Dyer, Kyle R; White, Jason M; Bochner, Felix

2000-01-01

Aims To investigate the steady-state pharmacokinetics of (R)- and (S)-methadone in a methadone maintenance population. Methods Eighteen patients recruited from a public methadone maintenance program underwent an interdosing interval pharmacokinetic study. Plasma and urine samples were collected and analysed for methadone and its major metabolite (EDDP) using stereoselective h.p.l.c. Methadone plasma protein binding was examined using ultrafiltration, and plasma α1-acid glycoprotein concentrations were quantified by radial immunoassay. Results (R)-methadone had a significantly (P < 0.05) greater unbound fraction (mean 173%) and total renal clearance (182%) compared with (S)-methadone, while maximum measured plasma concentrations (83%) and apparent partial clearance of methadone to EDDP (76%) were significantly (P < 0.001) lower. When protein binding was considered (R)-methadone plasma clearance of the unbound fraction (59%) and apparent partial intrinsic clearance to EDDP (44%) were significantly (P < 0.01) lower than for (S)-methadone, while AUCτSS, (167%) was significantly (P < 0.001) greater. There were no significant (P > 0.2) differences between the methadone enantiomers for AUCτSS, steady-state plasma clearance, trough plasma concentrations and unbound renal clearance. Patients excreted significantly (P < 0.0001) more (R)-methadone and (S)-EDDP than the corresponding enantiomers. Considerable interindividual variability was observed for the pharmacokinetic parameters, with coefficients of variation of up to 70%. Conclusions Steady-state pharmacokinetics of unbound methadone are stereoselective, and there is large interindividual variability consistent with CYP3A4 mediated metabolism to the major metabolite EDDP; the variability did not obscure a significant dose-plasma concentration relationship. Stereoselective differences in the pharmacokinetics of methadone may have important implications for pharmacokinetic-pharmacodynamic modelling but is unlikely to be important for therapeutic drug monitoring of methadone, in the setting of opioid dependence. PMID:11069437

Design considerations for point-of-care clinical trials comparing methadone and buprenorphine treatment for opioid dependence in pregnancy and for neonatal abstinence syndrome.

PubMed

Winhusen, Theresa; Wilder, Christine; Wexelblatt, Scott L; Theobald, Jeffrey; Hall, Eric S; Lewis, Daniel; Van Hook, James; Marcotte, Michael

2014-09-01

In recent years, the U.S. has experienced a significant increase in the prevalence of pregnant opioid-dependent women and of neonatal abstinence syndrome (NAS), which is caused by withdrawal from in-utero drug exposure. While methadone-maintenance currently is the standard of care for opioid dependence during pregnancy, research suggests that buprenorphine-maintenance may be associated with shorter infant hospital lengths of stay (LOS) relative to methadone-maintenance. There is no "gold standard" treatment for NAS but there is evidence that buprenorphine, relative to morphine or methadone, treatment may reduce LOS and length of treatment. Point-of-care clinical trial (POCCT) designs, maximizing external validity while reducing cost and complexity associated with classic randomized clinical trials, were selected for two planned trials to compare methadone to buprenorphine treatment for opioid dependence during pregnancy and for NAS. This paper describes design considerations for the Medication-assisted treatment for Opioid-dependent expecting Mothers (MOMs; estimated N = 370) and Investigation of Narcotics for Ameliorating Neonatal abstinence syndrome on Time in hospital (INFANTs; estimated N = 284) POCCTs, both of which are randomized, intent-to-treat, two-group trials. Outcomes would be obtained from participants' electronic health record at three participating hospitals. Additionally, a subset of infants in the INFANTs POCCT would be from mothers in the MOMs POCCT and, thus, potential interaction between medication treatment of mother and infant could be evaluated. This pair of planned POCCTs would evaluate the comparative effectiveness of treatments for opioid dependence during pregnancy and for NAS. The results could have a significant impact on practice. Copyright © 2014 Elsevier Inc. All rights reserved.

Antinociceptive Effect of Ghrelin in a Rat Model of Irritable Bowel Syndrome Involves TRPV1/Opioid Systems.

PubMed

Mao, Yuqing; Li, Zhengyang; Chen, Kan; Yu, Huafang; Zhang, Shaoren; Jiang, Miao; Ma, Yuanhua; Liang, Chunli; Liu, Hongyan; Li, Huanqing; Hua, Qian; Zhou, Hao; Sun, Yonghong; Fan, Xiaoming

2017-01-01

Irritable bowel syndrome (IBS), defined as recurrent abdominal pain and changes in bowel habits, seriously affects quality of life and ability to work. Ghrelin is a brain-gut hormone, which has been reported to show antinociceptive effects in peripheral pain. We investigated the effect of ghrelin on visceral hypersensitivity and pain in a rat model of IBS. Maternal deprivation (MD) was used to provide a stress-induced model of IBS in Wistar rats. Colorectal distension (CRD) was used to detect visceral sensitivity, which was evaluated by abdominal withdrawal reflex (AWR) scores. Rats that were confirmed to have visceral hypersensitivity after MD were injected with ghrelin (10 µg/kg) subcutaneously twice a week from weeks 7 to 8. [D-Lys3]-GHRP-6 (100 nmol/L) and naloxone (100 nmol/L) were administered subcutaneously to block growth hormone secretagogue receptor 1α (GHS-R1α) and opioid receptors, respectively. Expression of transient receptor potential vanilloid type 1 (TRPV1) and µ and κ opioid receptors (MOR and KOR) in colon, dorsal root ganglion (DRG) and cerebral cortex tissues were detected by western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), immunohistochemical analyses and immunofluorescence. Ghrelin treatment increased expression of opioid receptors and inhibited expression of TRPV1 in colon, dorsal root ganglion (DRG) and cerebral cortex. The antinociceptive effect of ghrelin in the rat model of IBS was partly blocked by both the ghrelin antagonist [D-Lys3]-GHRP-6 and the opioid receptor antagonist naloxone. The results indicate that ghrelin exerted an antinociceptive effect, which was mediated via TRPV1/opioid systems, in IBS-induced visceral hypersensitivity. Ghrelin might potentially be used as a new treatment for IBS. © 2017 The Author(s). Published by S. Karger AG, Basel.

Long-Term Antihyperalgesic and Opioid-Sparing Effects of 5-Day Ketamine and Morphine Infusion ("Burst Ketamine") in Diabetic Neuropathic Rats.

PubMed

Mak, Plato; Broadbear, Jillian H; Kolosov, Anton; Goodchild, Colin S

2015-09-01

"Burst ketamine" (BK) is the long-term infusion of subanesthetic ketamine in combination with an opioid. It is used clinically with mixed success to provide long-term pain relief and improve opioid response in patients. BK has not been simulated preclinically, therefore, its effectiveness was investigated in an animal model of neuropathic pain--streptozotocin-induced diabetic neuropathy. Diabetic neuropathic rats were randomized to receive a subcutaneous infusion of ketamine 20 mg/kg/day plus morphine 20 mg/kg/day (BK), either drug alone at the same dose, or sham treatment. Drugs were administered continuously over 5 days via osmotic minipump. Antihyperalgesic effects and antinociceptive responsiveness to morphine (0.625-10 mg/kg, i.p.) were assessed at 2, 4, 6, and 12 weeks post-treatment using paw withdrawal latency (PWL) from noxious heat (thermal hyperalgesia) and mechanical touch (tactile allodynia). Antihyperalgesic effects with significant increases in PWL from noxious heat occurred following BK and ketamine-only infusion, persisting 12 and 4 weeks, respectively. Opioid-sparing effects from noxious heat with increased sensitivity to morphine analgesia also occurred for 6 weeks after BK and 2 weeks after ketamine treatment; acute treatment with the maximum nonsedating dose of morphine (5 mg/kg) produced an antinociceptive effect in these two groups, but not in sham-treated rats. In morphine-only infusion rats, hyperalgesia and opioid insensitivity were both increased. This is the first preclinical study to use a model of neuropathic pain to demonstrate the utility of the BK procedure for delivering a long-lasting reduction in hyperalgesia and improved antinociceptive responsiveness to opioids. Wiley Periodicals, Inc.

ABCB1 genetic variability and methadone dosage requirements in opioid-dependent individuals.

PubMed

Coller, Janet K; Barratt, Daniel T; Dahlen, Karianne; Loennechen, Morten H; Somogyi, Andrew A

2006-12-01

The most common treatment for opioid dependence is substitution therapy with another opioid such as methadone. The methadone dosage is individualized but highly variable, and program retention rates are low due in part to nonoptimal dosing resulting in withdrawal symptoms and further heroin craving and use. Methadone is a substrate for the P-glycoprotein transporter, encoded by the ABCB1 gene, which regulates central nervous system exposure. This retrospective study aimed to investigate the influence of ABCB1 genetic variability on methadone dose requirements. Genomic deoxyribonucleic acid was isolated from opioid-dependent subjects (n = 60) and non-opioid-dependent control subjects (n = 60), and polymerase chain reaction-restriction fragment length polymorphism and allele-specific polymerase chain reaction were used to determine the presence of single nucleotide polymorphisms at positions 61, 1199, 1236, 2677, and 3435. ABCB1 haplotypes were inferred with PHASE software (version 2.1). There were no significant differences in the allele or genotype frequencies of the individual single nucleotide polymorphisms or haplotypes between the 2 populations. ABCB1 genetic variability influenced daily methadone dose requirements, such that subjects carrying 2 copies of the wild-type haplotype required higher doses compared with those with 1 copy and those with no copies (98.3 +/- 10.4, 58.6 +/- 20.9, and 55.4 +/- 26.1 mg/d, respectively; P = .029). In addition, carriers of the AGCTT haplotype required significantly lower doses than noncarriers (38.0 +/- 16.8 and 61.3 +/- 24.6 mg/d, respectively; P = .04). Although ABCB1 genetic variability is not related to the development of opioid dependence, identification of variant haplotypes may, after larger prospective studies have been performed, provide clinicians with a tool for methadone dosage individualization.

Impact of co-administration of oxycodone and smoked cannabis on analgesia and abuse liability.

PubMed

Cooper, Ziva D; Bedi, Gillinder; Ramesh, Divya; Balter, Rebecca; Comer, Sandra D; Haney, Margaret

2018-02-05

Cannabinoids combined with opioids produce synergistic antinociceptive effects, decreasing the lowest effective antinociceptive opioid dose (i.e., opioid-sparing effects) in laboratory animals. Although pain patients report greater analgesia when cannabis is used with opioids, no placebo-controlled studies have assessed the direct effects of opioids combined with cannabis in humans or the impact of the combination on abuse liability. This double-blind, placebo-controlled, within-subject study determined if cannabis enhances the analgesic effects of low dose oxycodone using a validated experimental model of pain and its effects on abuse liability. Healthy cannabis smokers (N = 18) were administered oxycodone (0, 2.5, and 5.0 mg, PO) with smoked cannabis (0.0, 5.6% Δ 9 tetrahydrocannabinol [THC]) and analgesia was assessed using the Cold-Pressor Test (CPT). Participants immersed their hand in cold water (4 °C); times to report pain (pain threshold) and withdraw the hand from the water (pain tolerance) were recorded. Abuse-related effects were measured and effects of oxycodone on cannabis self-administration were determined. Alone, 5.0 mg oxycodone increased pain threshold and tolerance (p ≤ 0.05). Although active cannabis and 2.5 mg oxycodone alone failed to elicit analgesia, combined they increased pain threshold and tolerance (p ≤ 0.05). Oxycodone did not increase subjective ratings associated with cannabis abuse, nor did it increase cannabis self-administration. However, the combination of 2.5 mg oxycodone and active cannabis produced small, yet significant, increases in oxycodone abuse liability (p ≤ 0.05). Cannabis enhances the analgesic effects of sub-threshold oxycodone, suggesting synergy, without increases in cannabis's abuse liability. These findings support future research into the therapeutic use of opioid-cannabinoid combinations for pain.

Possible evidence for re-regulation of HPA axis and brain reward systems over time in treatment in prescription opioid-dependent patients.

PubMed

Bunce, Scott C; Harris, Jonathan D; Bixler, Edward O; Taylor, Megan; Muelly, Emilie; Deneke, Erin; Thompson, Kenneth W; Meyer, Roger E

2015-01-01

There is growing evidence for a neuroadaptive model underlying vulnerability to relapse in opioid dependence. The purpose of this study was to evaluate clinical measures hypothesized to mirror elements of allostatic dysregulation in patients dependent on prescription opioids at 2 time points after withdrawal, compared with healthy control participants. Recently withdrawn (n = 7) prescription opioid-dependent patients were compared with the patients in supervised residential care for 2 to 3 months (extended care; n = 7) and healthy controls (n = 7) using drug cue reactivity, affect-modulated startle response tasks, salivary cortisol, and 8 days of sleep actigraphy. Prefrontal cortex was monitored with functional near-infrared spectroscopy during the cue reactivity task. Startle response results indicated reduced hedonic response to natural rewards among patients recently withdrawn from opioids relative to extended care patients. The recently withdrawn patients showed increased activation to pill stimuli in right dorsolateral prefrontal cortex relative to extended care patients. Cortisol levels were elevated among recently withdrawn patients and intermediate for extended care relative to healthy controls. Actigraphy indicated disturbed sleep between recently withdrawn patients and extended care patients; extended care patients were similar to controls. Dorsolateral prefrontal cortex activation to drug and natural reward cues, startle responses to natural reward cues, day-time cortisol levels, time in bed, and total time spent sleeping were all correlated with the number of days since last drug use (ie, time in supervised residential treatment). These results suggest possible re-regulation of dysregulated hypothalamic-pituitary-adrenal axis and brain reward systems in prescription opioid-dependent patients over the drug-free period in residential treatment.

Differential involvement of 3', 5'-cyclic adenosine monophosphate-dependent protein kinase in regulation of Fos and tyrosine hydroxylase expression in the heart after naloxone induced morphine withdrawal.

PubMed

Almela, Pilar; Cerezo, Manuela; González-Cuello, A; Milanés, M Victoria; Laorden, M Luisa

2007-01-01

We previously demonstrated that morphine withdrawal induced hyperactivity of the heart by the activation of noradrenergic pathways innervating the left and right ventricle, as evaluated by noradrenaline (NA) turnover and Fos expression. We investigated whether cAMP-dependent protein kinase (PKA) plays a role in this process by estimating changes in PKA immunoreactivity and the influence of inhibitor of PKA on Fos protein expression, tyrosine hydroxylase (TH) immunoreactivity levels and NA turnover in the left and right ventricle. Dependence on morphine was induced by a 7-day s.c. implantation of morphine pellets. Morphine withdrawal was precipitated on day 8 by an injection of naloxone (5 mg/kg). When opioid withdrawal was precipitated, an increase in PKA immunoreactivity and phospho-CREB (cyclic AMP response element protein) levels were observed in the heart. Moreover, morphine withdrawal induces Fos expression, an enhancement of NA turnover and an increase in the total TH levels. When the selective PKA inhibitor HA-1004 was infused, concomitantly with morphine pellets, it diminished the increase in NA turnover and the total TH levels observed in morphine-withdrawn rats. However, this inhibitor neither modifies the morphine withdrawal induced Fos expression nor the increase of nonphosphorylated TH levels. The present findings indicate that an up-regulated PKA-dependent transduction pathway might contribute to the activation of the cardiac catecholaminergic neurons in response to morphine withdrawal and suggest that Fos is not a target of PKA at heart levels.

Pain in the Frail or Elderly Patient: Does Tapentadol Have a Role?

PubMed

Veal, Felicity C; Peterson, Gregory M

2015-06-01

Persistent pain affects the elderly disproportionally, occurring in 50% of elderly community-dwelling patients and 80% of aged care residents. The management of pain in the elderly and frail patient is complicated because of the risks posed by changes in pharmacokinetics and pharmacodynamics, polypharmacy, and drug-disease interactions. Trials evaluating the efficacy of analgesics have often excluded elderly patients and universally excluded frail patients; therefore, the true efficacy and side-effect profiles in these population groups are largely unknown, especially for long-term use. A stepwise approach is recommended to managing pain, commencing with paracetamol and adding on opioids when needed to manage pain. However, because of the short duration of clinical trials, exclusion of frail patients, and minimal inclusion of elderly patients, the decision as to which opioid should be added on to paracetamol is a difficult one. This article reviews the evidence surrounding a newer opioid, tapentadol. Tapentadol acts on both the mu receptors and on neuronal reuptake of noradrenaline, and has no significant analgesically active metabolites, which theoretically presents some advantages, particularly in comparison with tramadol. However, the evidence to support tapentadol is weak and the trials were often methodologically poor and sponsored almost universally by the drug company. Currently, there is insufficient evidence to support the use of tapentadol over other opioids, which have been on the market longer, are less expensive, and have better established safety profiles. As a first-line agent after the failure of paracetamol alone, morphine, oxycodone, fentanyl, or buprenorphine are still the preferred evidence-based choices for add-on opioid therapy for elderly or frail patients.

Label-Free Proteomic Analysis of Protein Changes in the Striatum during Chronic Ethanol Use and Early Withdrawal

PubMed Central

Ayers-Ringler, Jennifer R.; Oliveros, Alfredo; Qiu, Yanyan; Lindberg, Daniel M.; Hinton, David J.; Moore, Raymond M.; Dasari, Surendra; Choi, Doo-Sup

2016-01-01

The molecular mechanisms underlying the neuronal signaling changes in alcohol addiction and withdrawal are complex and multifaceted. The cortico-striatal circuit is highly implicated in these processes, and the striatum plays a significant role not only in the early stages of addiction, but in the developed-addictive state as well, including withdrawal symptoms. Transcriptional analysis is a useful method for determining changes in gene expression, however, the results do not always accurately correlate with protein levels. In this study, we employ label-free proteomic analysis to determine changes in protein expression within the striatum during chronic ethanol use and early withdrawal. The striatum, composed primarily of medium spiny GABAergic neurons, glutamatergic and dopaminergic nerve terminals and astrocytes, is relatively homogeneous for proteomic analysis. We were able to analyze more than 5000 proteins from both the dorsal (caudate and putamen) and ventral (nucleus accumbens) striatum and identified significant changes following chronic intermittent ethanol exposure and acute (8 h) withdrawal compared to ethanol naïve and ethanol exposure groups respectively. Our results showed significant changes in proteins involved in glutamate and opioid peptide signaling, and also uncovered novel pathways including mitochondrial function and lipid/cholesterol metabolism, as revealed by changes in electron transport chain proteins and RXR activation pathways. These results will be useful in the development of novel treatments for alcohol withdrawal and thereby aid in recovery from alcohol use disorder. PMID:27014007

Pharmacokinetics of 2 Formulations of Transdermal Fentanyl in Cynomolgus Macaques (Macaca fascicularis)

PubMed Central

Carlson, Amy M; Kelly, Richard; Fetterer, David P; Rico, Pedro J; Bailey, Emily J

2016-01-01

Fentanyl is a μ-opioid agonist that often is used as the analgesic component for balanced anesthesia in both human and veterinary patients. Minimal information has been published regarding appropriate dosing, and the pharmacokinetics of fentanyl are unknown in NHP. The pharmacokinetic properties of 2 transdermal fentanyl delivery methods, a solution (2.6 and 1.95 mg/kg) and a patch (25 µg/h), were determined when applied topically to the dorsal scapular area of cynomolgus macaques (Macaca fascicularis). Serum fentanyl concentrations were analyzed by using liquid chromatography–mass spectrometry. Compared with the patch, the transdermal fentanyl solution generated higher drug concentrations over longer time. Adverse reactions occurred in the macaques that received the transdermal fentanyl solution at 2.6 mg/kg. Both preparations showed significant interanimal variability in the maximal serum drug levels, time to achieve maximal fentanyl levels, elimination half-life, and AUC values. Both the maximal concentration and the time at which this concentration occurred were increased in macaques compared with most other species after application of the transdermal fentanyl patch and compared with dogs after application of the transdermal fentanyl solution. The pharmacokinetic properties of transdermal fentanyl in macaques are markedly different from those in other veterinary species and preclude its use as a long-acting analgesic drug in NHP. PMID:27423151

Treatment of neonatal abstinence syndrome.

PubMed

Johnson, K; Gerada, C; Greenough, A

2003-01-01

Neonatal abstinence syndrome (NAS) is suffered by infants withdrawing from substances on which they have become physically dependent after in utero exposure. They may require prolonged treatment and spend weeks or even months in hospital. A wide range of drugs have been used to treat NAS. The efficacy of few, however, have been adequately investigated. Evidence suggests that opioids are the most appropriate, at least in infants exposed to diamorphine or methadone. In all "head to head" trials, diazepam has been shown to be ineffective. Morphine and methadone are currently the most commonly prescribed opioids to treat NAS, but randomised trials have not been undertaken to determine which is the more beneficial. Many infants with NAS have been exposed to multiple substances in utero. Further research is required into whether a single opiate or a multiple drug regimen is the best option for such patients.

Pharmacogenetic analysis of opioid dependence treatment dose and dropout rate.

PubMed

Crist, Richard C; Li, James; Doyle, Glenn A; Gilbert, Alex; Dechairo, Bryan M; Berrettini, Wade H

2018-01-01

Currently, no pharmacogenetic tests for selecting an opioid-dependence pharmacotherapy have been approved by the US Food and Drug Administration. Determine the effects of variants in 11 genes on dropout rate and dose in patients receiving methadone or buprenorphine/naloxone (ClinicalTrials.gov Identifier: NCT00315341). Variants in six pharmacokinetic genes (CYP1A2, CYP2B6, CYP2C19, CYP2C9, CYP2D6, CYP3A4) and five pharmacodynamic genes (HTR2A, OPRM1, ADRA2A, COMT, SLC6A4) were genotyped in samples from a 24-week, randomized, open-label trial of methadone and buprenorphine/naloxone for the treatment of opioid dependence (n = 764; 68.7% male). Genotypes were then used to determine the metabolism phenotype for each pharmacokinetic gene. Phenotypes or genotypes for each gene were analyzed for association with dropout rate and mean dose. Genotype for 5-HTTLPR in the SLC6A4 gene was nominally associated with dropout rate when the methadone and buprenorphine/naloxone groups were combined. When the most significant variants associated with dropout rate were analyzed using pairwise analyses, SLC6A4 (5-HTTLPR) and COMT (Val158Met; rs4860) had nominally significant associations with dropout rate in methadone patients. None of the genes analyzed in the study was associated with mean dose of methadone or buprenorphine/naloxone. This study suggests that functional polymorphisms related to synaptic dopamine or serotonin levels may predict dropout rates during methadone treatment. Patients with the S/S genotype at 5-HTTLPR in SLC6A4 or the Val/Val genotype at Val158Met in COMT may require additional treatment to improve their chances of completing addiction treatment. Replication in other methadone patient populations will be necessary to ensure the validity of these findings.

Comparison of continuous subcutaneous and intravenous hydromorphone infusions for management of cancer pain.

PubMed

Moulin, D E; Kreeft, J H; Murray-Parsons, N; Bouquillon, A I

1991-02-23

To compare the safety and efficacy of subcutaneous and intravenous infusion of opioid analgesics, a randomised, double-blind, crossover trial was carried out in inpatients. 15 patients with severe cancer pain received two 48 h infusions of hydromorphone--one subcutaneously and one intravenously in randomly allocated order. The study was made double-blind by the use of two infusion pumps throughout; during the active subcutaneous infusion the intravenous pump delivered saline and vice versa. Serial measurements of pain intensity, pain relief, mood, and sedation by means of visual analogue scales showed no clinically or statistically significant difference between the two infusion routes. Side-effects were slight, and the mean number of morphine injections for breakthrough pain did not differ significantly between the routes (4.8 [SD 4.5] for intravenous vs 5.3 [5.6] for subcutaneous). Plasma hydromorphone concentrations measured at 24 h and 48 h of infusion showed stable steady-state pharmacokinetics; the mean bioavailability from subcutaneous infusion was 78% of that with intravenous infusion. Because of the simplicity, technical advantages, and cost-effectiveness of continuous subcutaneous opioid infusion into the chest wall or trunk, intravenous opioid infusion for the management of severe cancer pain should be abandoned.

New formulations of bupivacaine for the treatment of postoperative pain: liposomal bupivacaine and SABER-Bupivacaine.

PubMed

Skolnik, Aaron; Gan, Tong J

2014-08-01

Although generally considered both safe and effective, local anesthetics are often used in conjunction with opioids postoperatively in part because of the limited duration of drug action of local anesthetics. Much interest exists in extending the duration of local anesthetics' effects, which may reduce the requirement for opioid pain medications that are frequently associated with side effects, including nausea and vomiting, pruritus and respiratory depression. This article introduces liposomal bupivacaine and SABER®-Bupivacaine, two new formulations of bupivacaine that increase the duration of analgesia postoperatively through two novel slow-release technologies. The pharmacodynamics, pharmacokinetics, efficacy and safety of both preparations of bupivacaine are reviewed. An electronic database search conducted using the Cochrane Central Register of Controlled Trials and MEDLINE/PubMed with the following search terms: 'bupivacaine,' 'liposomal bupivacaine', 'liposome bupivacaine', 'Exparel', 'SABER-Bupivacaine', 'SABER Bupivacaine', and 'SABER' yielded 90 articles (no language or date of publication restrictions were imposed). Clinical trials involving liposomal bupivacaine and SABER-Bupivacaine indicate that both safely prolong analgesia, while decreasing opioid requirements when compared with placebo. However, additional clinical studies are necessary to better determine the efficacy and cost-effectiveness of these long-acting local anesthetic formulations.

Short-term sleep disturbance-induced stress does not affect basal pain perception, but does delay postsurgical pain recovery

PubMed Central

Wang, Po-Kai; Cao, Jing; Wang, Hongzhen; Liang, Lingli; Zhang, Jun; Lutz, Brianna Marie; Shieh, Kun-Ruey; Bekker, Alex; Tao, Yuan-Xiang

2015-01-01

Chronic sleep disturbance-induced stress is known to increase basal pain sensitivity. However, most surgical patients frequently report short-term sleep disturbance/deprivation during pre- and post-operation periods and have normal pain perception pre-surgery. Whether this short-term sleep disturbance affects postsurgical pain is elusive. We here reported that pre- or post-exposure to rapid eye movement sleep disturbance (REMSD) 6 h daily for 3 consecutive days did not alter basal responses to mechanical, heat, and cold stimuli, but did delay recovery in incision-induced reductions in paw withdrawal threshold to mechanical stimulation and paw withdrawal latencies to heat and cold stimuli on the ipsilateral side of male or female rats. This short-term REMSD led to stress evidenced by an increase in swim immobility time, a decrease in sucrose consumption, and an elevation in the level of corticosterone in serum. Blocking this stress via intrathecal RU38486 or bilateral adrenalectomy abolished REMSD-caused delay in recovery of incision-induced reductions in behavioral responses to mechanical, heat, and cold stimuli. Moreover, this short-term REMSD produced significant reductions in the levels of mu opioid receptor and kappa opioid receptor, but not Kv1.2, in the ipsilateral L4/5 spinal cord and dorsal root ganglia on day 9 post-incision (but not post-sham surgery). PMID:26342649

Pharmacokinetics and tissue elimination of flunixin in veal calves.

PubMed

Kissell, Lindsey W; Brinson, Patrick D; Gehring, Ronette; Tell, Lisa A; Wetzlich, Scott E; Baynes, Ronald E; Riviere, Jim E; Smith, Geof W

2016-06-01

OBJECTIVE To describe plasma pharmacokinetic parameters and tissue elimination of flunixin in veal calves. ANIMALS 20 unweaned Holstein calves between 3 and 6 weeks old. PROCEDURES Each calf received flunixin (2.2 mg/kg, IV, q 24 h) for 3 days. Blood samples were collected from all calves before the first dose and at predetermined times after the first and last doses. Beginning 24 hours after injection of the last dose, 4 calves were euthanized each day for 5 days. Plasma and tissue samples were analyzed by ultraperformance liquid chromatography. Pharmacokinetic parameters were calculated by compartmental and noncompartmental methods. RESULTS Mean ± SD plasma flunixin elimination half-life, residence time, and clearance were 1.32 ± 0.94 hours, 12.54 ± 10.96 hours, and 64.6 ± 40.7 mL/h/kg, respectively. Mean hepatic and muscle flunixin concentrations decreased to below FDA-established tolerance limits (0.125 and 0.025 μg/mL, respectively) for adult cattle by 3 and 2 days, respectively, after injection of the last dose of flunixin. Detectable flunixin concentrations were present in both the liver and muscle for at least 5 days after injection of the last dose. CONCLUSIONS AND CLINICAL RELEVANCE The labeled slaughter withdrawal interval for flunixin in adult cattle is 4 days. Because administration of flunixin to veal calves represents extralabel drug use, any detectable flunixin concentrations in edible tissues are considered a violation. Results indicated that a slaughter withdrawal interval of several weeks may be necessary to ensure that violative tissue residues of flunixin are not detected in veal calves treated with that drug.

Adolescent Community Reinforcement Approach implementation and treatment outcomes for youth with opioid problem use.

PubMed

Godley, Mark D; Passetti, Lora L; Subramaniam, Geetha A; Funk, Rodney R; Smith, Jane Ellen; Meyers, Robert J

2017-05-01

This paper compares adolescents with primary opioid problem use (OPU) to those with primary marijuana or alcohol problem use (MAPU) who received up to six months of Adolescent Community Reinforcement Approach (A-CRA), an empirically supported treatment. Intake clinical characteristics, treatment implementation measures, and clinical outcomes of two substance problem groups (OPU and MAPU) were compared using data from 1712 adolescents receiving A-CRA treatment. Data were collected at intake and 3, 6, and 12 months post-intake. At intake, adolescents in the OPU group were more likely than those in the MAPU group to be Caucasian, older, female, and not attending school; report greater substance and mental health problems; and engage in social and health risk behaviors. There was statistical equivalence between groups in rates of A-CRA treatment initiation, engagement, retention, and satisfaction. Both groups decreased significantly on most substance use outcomes, with the OPU group showing greater improvement; however, the OPU group had more severe problems at intake and continued to report higher frequency of opioid use and more days of emotional problems and residential treatment over 12 months. The feasibility and acceptability of A-CRA for OPUs was demonstrated. Despite significantly greater improvement by the OPU group, they did not improve to the level of the MAPU group over 12 months, suggesting that they may benefit from A-CRA continuing care up to 12 months, medication to address opioid withdrawal and craving, and the inclusion of opioid-focused A-CRA procedures. Copyright © 2017 Elsevier B.V. All rights reserved.

Yohimbine Increases Opioid-Seeking Behavior in Heroin-Dependent, Buprenorphine-Maintained Individuals

PubMed Central

Greenwald, Mark K.; Lundahl, Leslie H.; Steinmiller, Caren L.

2012-01-01

Rationale In laboratory animals, the biological stressor yohimbine (α2-noradrenergic autoreceptor antagonist) promotes drug seeking. Human laboratory studies have demonstrated that psychological stressors can increase drug craving but not that stressors alter drug seeking. Objectives This clinical study tested whether yohimbine increases opioid seeking behavior. Methods Ten heroin-dependent, buprenorphine (8-mg/day) stabilized volunteers, sampled two doses of hydromorphone (12 and 24 mg IM in counterbalanced order, labeled Drug A [session 1] and Drug B [session 2]). During each of six later sessions (within-subject, double blind, randomized crossover design), volunteers could respond on a 12-trial choice progressive ratio task to earn units (1 or 2 mg) of the sampled hydromorphone dose (Drug A or B) vs. money ($2) following different oral yohimbine pretreatment doses (0, 16.2 and 32.4 mg). Results Behavioral economic demand intensity and peak responding (Omax) were significantly higher for hydromorphone 2-mg than 1-mg. Relative to placebo, yohimbine significantly increased hydromorphone demand inelasticity, more so for hydromorphone 1-mg units (Pmax = 909, 3647 and 3225 for placebo, 16.2 and 32.4 mg yohimbine doses, respectively) than hydromorphone 2-mg units (Pmax = 2656, 3193 and 3615, respectively). Yohimbine produced significant but clinically modest dose-dependent increases in blood pressure (systolic ≈15 and diastolic ≈10 mmHg) and opioid withdrawal symptoms, and decreased opioid agonist symptoms and elated mood. Conclusions These findings concur with preclinical data by demonstrating that yohimbine increases drug seeking; in this study, these effects occurred without clinically significant subjective distress or elevated craving, and partly depended on opioid unit dose. PMID:23161001

Developmental Potential for Endomorphin Opioidmimetic Drugs

PubMed Central

Okada, Yoshio; Tsuda, Yuko; Salvadori, Severo; Lazarus, Lawrence H.

2012-01-01

Morphine, which is agonist for μ-opioid receptors, has been used as an anti-pain drug for millennia. The opiate antagonists, naloxone and naltrexone, derived from morphine, were employed for drug addiction and alcohol abuse. However, these exogenous agonists and antagonists exhibit numerous and unacceptable side effects. Of the endogenous opioid peptides, endomorphin(EM)-1 and endomorphin(EM)-2 with their high μ-receptor affinity and exceptionally high selectivity relative to δ- and κ-receptors in vitro and in vivo provided a sufficiently sequence-flexible entity in order to prepare opioid-based drugs. We took advantage of this unique feature of the endomorphins by exchanging the N-terminal residue Tyr1 with 2′,6′-dimethyl-l-tyrosine (Dmt) to increase their stability and the spectrum of bioactivity. We systematically altered specific residues of [Dmt1]EM-1 and [Dmt1]EM-2 to produce various analogues. Of these analogues, [N-allyl-Dmt1]EM-1 (47) and [N-allyl-Dmt1]EM-2 (48) exhibited potent and selective antagonism to μ-receptors: they completely inhibited naloxone- and naltrexone-induced withdrawal from following acute morphine dependency in mice and reversed the alcohol-induced changes observed in sIPSC in hippocampal slices. Overall, we developed novel and efficacious opioid drugs without deleterious side effects that were able to resist enzymatic degradation and were readily transported intact through epithelial membranes in the gastrointestinal tract and the blood-brain-barrier. PMID:25954530

Cardiac conduction disturbance after loperamide abuse.

PubMed

Marraffa, J M; Holland, M G; Sullivan, R W; Morgan, B W; Oakes, J A; Wiegand, T J; Hodgman, M J

2014-11-01

Prescription opioid abuse is a major public health concern and an ongoing epidemic in the United States. Loperamide is a widely available and inexpensive over-the-counter antidiarrheal with peripheral mu-opioid receptor activity. Online resources discuss the use of loperamide for the amelioration of withdrawal symptoms or recreational abuse. We describe the clinical course of 5 patients abusing loperamide, 3 of whom had life-threatening cardiac arrhythmias. In this observational case series, patients with cardiac arrhythmias or history of loperamide abuse with cardiac arrhythmias were identified; 5 patients were identified and 4 of the 5 patients were seen directly at the bedside. Clinical profile and outcome of patients is reported. We report 5 patients with history of loperamide abuse; 3 of the 5 patients had life-threatening cardiac arrhythmias. One of the patients experienced a second life-threatening arrhythmia after he resumed loperamide abuse. Loperamide levels were obtained in 4 of the 5 patients and were at least one order of magnitude greater than therapeutic concentrations. Discontinuation of loperamide resulted in complete resolution of cardiac conduction disturbances. This case series describes several patients with cardiac conduction abnormalities and life-threatening ventricular arrhythmias temporally related to loperamide abuse. With the recent efforts to restrict the diversion of prescription opioids, increasing abuse of loperamide as an opioid substitute may be seen. Toxicologists should be aware of these risks and we urge all clinicians to report such cases to FDA Medwatch(®).

Methadone continuation versus forced withdrawal on incarceration in a combined US prison and jail: a randomised, open-label trial.

PubMed

Rich, Josiah D; McKenzie, Michelle; Larney, Sarah; Wong, John B; Tran, Liem; Clarke, Jennifer; Noska, Amanda; Reddy, Manasa; Zaller, Nickolas

2015-07-25

Methadone is an effective treatment for opioid dependence. When people who are receiving methadone maintenance treatment for opioid dependence are incarcerated in prison or jail, most US correctional facilities discontinue their methadone treatment, either gradually, or more often, abruptly. This discontinuation can cause uncomfortable symptoms of withdrawal and renders prisoners susceptible to relapse and overdose on release. We aimed to study the effect of forced withdrawal from methadone upon incarceration on individuals' risk behaviours and engagement with post-release treatment programmes. In this randomised, open-label trial, we randomly assigned (1:1) inmates of the Rhode Island Department of Corrections (RI, USA) who were enrolled in a methadone maintenance-treatment programme in the community at the time of arrest and wanted to remain on methadone treatment during incarceration and on release, to either continuation of their methadone treatment or to usual care--forced tapered withdrawal from methadone. Participants could be included in the study only if their incarceration would be more than 1 week but less than 6 months. We did the random assignments with a computer-generated random permutation, and urn randomisation procedures to stratify participants by sex and race. Participants in the continued-methadone group were maintained on their methadone dose at the time of their incarceration (with dose adjustments as clinically indicated). Patients in the forced-withdrawal group followed the institution's standard withdrawal protocol of receiving methadone for 1 week at the dose at the time of their incarceration, then a tapered withdrawal regimen (for those on a starting dose >100 mg, the dose was reduced by 5 mg per day to 100 mg, then reduced by 3 mg per day to 0 mg; for those on a starting dose >100 mg, the dose was reduced by 3 mg per day to 0 mg). The main outcomes were engagement with a methadone maintenance-treatment clinic after release from incarceration and time to engagement with methadone maintenance treatment, by intention-to-treat and as-treated analyses, which we established in a follow-up interview with the participants at 1 month after their release from incarceration. Our study paid for 10 weeks of methadone treatment after release if participants needed financial help. This trial is registered with ClinicalTrials.gov, number NCT01874964. Between June 14, 2011, and April 3, 2013, we randomly assigned 283 prisoners to our study, 142 to continued methadone treatment, and 141 to forced withdrawal from methadone. Of these, 60 were excluded because they did not fit the eligibility criteria, leaving 114 in the continued-methadone group and 109 in the forced-withdrawal group (usual care). Participants assigned to continued methadone were more than twice as likely than forced-withdrawal participants to return to a community methadone clinic within 1 month of release (106 [96%] of 110 in the continued-methadone group compared with 68 [78%] of 87 in the forced-withdrawal group; adjusted hazard ratio [HR] 2·04, 95% CI 1·48-2·80). We noted no differences in serious adverse events between groups. For the continued-methadone and forced-withdrawal groups, the number of deaths were one and zero, non-fatal overdoses were one and two, admissions to hospital were one and four; and emergency-room visits were 11 and 16, respectively. Although our study had several limitations--eg, it only included participants incarcerated for fewer than 6 months, we showed that forced withdrawal from methadone on incarceration reduced the likelihood of prisoners re-engaging in methadone maintenance after their release. Continuation of methadone maintenance during incarceration could contribute to greater treatment engagement after release, which could in turn reduce the risk of death from overdose and risk behaviours. National Institute on Drug Abuse and the Lifespan/Tufts/Brown Center for AIDS Research from the National Institutes of Health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Methadone continuation versus forced withdrawal on incarceration in a combined US prison and jail: a randomised, open-label trial

PubMed Central

Rich, Josiah D; McKenzie, Michelle; Larney, Sarah; Wong, John B; Tran, Liem; Clarke, Jennifer; Noska, Amanda; Reddy, Manasa; Zaller, Nickolas

2015-01-01

Summary Background Methadone is an effective treatment for opioid dependence. When people who are receiving methadone maintenance treatment for opioid dependence are incarcerated in prison or jail, most US correctional facilities discontinue their methadone treatment, either gradually, or more often, abruptly. This discontinuation can cause uncomfortable symptoms of withdrawal and renders prisoners susceptible to relapse and overdose on release. We aimed to study the effect of forced withdrawal from methadone upon incarceration on individuals’ risk behaviours and engagement with post-release treatment programmes. Methods In this randomised, open-label trial, we randomly assigned (1:1) inmates of the Rhode Island Department of Corrections (RI, USA) who were enrolled in a methadone maintenance-treatment programme in the community at the time of arrest and wanted to remain on methadone treatment during incarceration and on release, to either continuation of their methadone treatment or to usual care—forced tapered withdrawal from methadone. Participants could be included in the study only if their incarceration would be more than 1 week but less than 6 months. We did the random assignments with a computer-generated random permutation, and urn randomisation procedures to stratify participants by sex and race. Participants in the continued-methadone group were maintained on their methadone dose at the time of their incarceration (with dose adjustments as clinically indicated). Patients in the forced-withdrawal group followed the institution’s standard withdrawal protocol of receiving methadone for 1 week at the dose at the time of their incarceration, then a tapered withdrawal regimen (for those on a starting dose >100 mg, the dose was reduced by 5 mg per day to 100 mg, then reduced by 3 mg per day to 0 mg; for those on a starting dose ≤100 mg, the dose was reduced by 3 mg per day to 0 mg). The main outcomes were engagement with a methadone maintenance-treatment clinic after release from incarceration and time to engagement with methadone maintenance treatment, by intention-to-treat and as-treated analyses, which we established in a follow-up interview with the participants at 1 month after their release from incarceration. Our study paid for 10 weeks of methadone treatment after release if participants needed financial help. This trial is registered with ClinicalTrials.gov, number NCT01874964. Findings Between June 14, 2011, and April 3, 2013, we randomly assigned 283 prisoners to our study, 142 to continued methadone treatment, and 141 to forced withdrawal from methadone. Of these, 60 were excluded because they did not fit the eligibility criteria, leaving 114 in the continued-methadone group and 109 in the forced-withdrawal group (usual care). Participants assigned to continued methadone were more than twice as likely than forced-withdrawal participants to return to a community methadone clinic within 1 month of release (106 [96%] of 110 in the continued-methadone group compared with 68 [78%] of 87 in the forced-withdrawal group; adjusted hazard ratio [HR] 2·04, 95% CI 1·48–2·80). We noted no differences in serious adverse events between groups. For the continued-methadone and forced-withdrawal groups, the number of deaths were one and zero, non-fatal overdoses were one and two, admissions to hospital were one and four; and emergency-room visits were 11 and 16, respectively. Interpretation Although our study had several limitations—eg, it only included participants incarcerated for fewer than 6 months, we showed that forced withdrawal from methadone on incarceration reduced the likelihood of prisoners re-engaging in methadone maintenance after their release. Continuation of methadone maintenance during incarceration could contribute to greater treatment engagement after release, which could in turn reduce the risk of death from overdose and risk behaviours. PMID:26028120

Reasons for Benzodiazepine Use Among Persons Seeking Opioid Detoxification

PubMed Central

Stein, Michael D.; Kanabar, Mitika; Anderson, Bradley J.; Lembke, Anna; Bailey, Genie L.

2016-01-01

Background Over the past decade, patients admitted to addiction treatment programs have reported increasing rates of concurrent opioid and benzodiazepine (BZD) use. This drug combination places individuals at high risk for accidental overdose. Little is known about reasons for BZD use among individuals seeking treatment for opioid use disorders. Methods We surveyed consecutive persons initiating inpatient opioid detoxification and identified 176 out of 438 who reported BZD use in the past 30 days and/or had a positive toxicology. Results Forty percent of persons surveyed used a BZD in the month prior to admission, and 25% of these met criteria for BZD dependence (DSM IV). BZD users averaged 32.0 years of age, 63.6% were male, 85.2% used heroin, and reported, on average, 13.3 (± 11.2) days of BZD use during the past month. Alprazolam (Xanax) was the most commonly used BZD (52%), and buying it on the street the most common source (48%). The most commonly reported reason for BZD use was ‘to manage anxiety’ (42.6%), followed by ‘to get or enhance a high’ (27.7%), ‘to help with sleep’ (11.4%), and ‘to decrease opioid withdrawal’ (10.2%). The most common reason for BZD use was significantly associated (p < .001) with most likely source of BZDs, with persons who got their BZDs from a prescriber (23%) more likely to report BZD anxiety as their primary reason for use, while persons who bought BZDs on “the street” (48%) had the highest likelihood of reporting using BZD to get or enhance a high. Participants using BZDs most commonly for anxiety did not endorse lower anxiety than those using BZDs for other reasons. Conclusions Two in five persons seeking detoxification for an opioid use disorder used a BZD in the prior month. Anxiety was the most common reason patients reported using a benzodiazepine, but they also reported using BZDs to enhance a ‘high’ and manage opioid withdrawal. Evidence-based discussions about the risks of combining BZDs and opioids, and alternatives to BZDs should be a high priority in detoxification settings. PMID:27431047

Development of a robust, sensitive and selective liquid chromatography-tandem mass spectrometry assay for the quantification of the novel macrocyclic peptide kappa opioid receptor antagonist [D-Trp]CJ-15,208 in plasma and application to an initial pharmacokinetic study.

PubMed

Khaliq, Tanvir; Williams, Todd D; Senadheera, Sanjeewa N; Aldrich, Jane V

2016-08-15

Selective kappa opioid receptor (KOR) antagonists may have therapeutic potential as treatments for substance abuse and mood disorders. Since [D-Trp]CJ-15,208 (cyclo[Phe-d-Pro-Phe-d-Trp]) is a novel potent KOR antagonist in vivo, it is imperative to evaluate its pharmacokinetic properties to assist the development of analogs as potential therapeutic agents, necessitating the development and validation of a quantitative method for determining its plasma levels. A method for quantifying [D-Trp]CJ-15,208 was developed employing high performance liquid chromatography-tandem mass spectrometry in mouse plasma. Sample preparation was accomplished through a simple one-step protein precipitation method with acetonitrile, and [D-Trp]CJ-15,208 analyzed following HPLC separation on a Hypersil BDS C8 column. Multiple reaction monitoring (MRM), based on the transitions m/z 578.1→217.1 and 245.0, was specific for [D-Trp]CJ-15,208, and MRM based on the transition m/z 566.2→232.9 was specific for the internal standard without interference from endogenous substances in blank mouse plasma. The assay was linear over the concentration range 0.5-500ng/mL with a mean r(2)=0.9987. The mean inter-day accuracy and precision for all calibration standards were 93-118% and 8.9%, respectively. The absolute recoveries were 85±6% and 81±9% for [D-Trp]CJ-15,208 and the internal standard, respectively. The analytical method had excellent sensitivity with a lower limit of quantification of 0.5ng/mL using a sample volume of 20μL. The method was successfully applied to an initial pharmacokinetic study of [D-Trp]CJ-15,208 following intravenous administration to mice. Copyright © 2016 Elsevier B.V. All rights reserved.

Development of a robust, sensitive and selective liquid chromatography-tandem mass spectrometry assay for the quantification of the novel macrocyclic peptide kappa opioid receptor antagonist [D-Trp]CJ-15,208 in plasma and application to an initial pharmacokinetic study

PubMed Central

Khaliq, Tanvir; Williams, Todd D.; Senadheera, Sanjeewa N.; Aldrich, Jane V.

2016-01-01

Selective kappa opioid receptor (KOR) antagonists may have therapeutic potential as treatments for substance abuse and mood disorders. Since [D-Trp]CJ-15,208 (cyclo[Phe-D-Pro-Phe-D-Trp]) is a novel potent KOR antagonist in vivo, it is imperative to evaluate its pharmacokinetic properties to assist the development of analogs as potential therapeutic agents, necessitating the development and validation of a quantitative method for determining its plasma levels. A method for quantifying [D-Trp]CJ-15,208 was developed employing high performance liquid chromatography-tandem mass spectrometry in mouse plasma. Sample preparation was accomplished through a simple one-step protein precipitation method with acetonitrile, and [D-Trp]CJ-15,208 analyzed following HPLC separation on a Hypersil BDS C8 column. Multiple reaction monitoring (MRM), based on the transitions m/z 578.1 → 217.1 and 245.0, was specific for [D-Trp]CJ-15,208, and MRM based on the transition m/z 566.2 → 232.9 was specific for the internal standard without interference from endogenous substances in blank mouse plasma. The assay was linear over the concentration range 0.5–500 ng/mL with a mean r2 = 0.9987. The mean inter-day accuracy and precision for all calibration standards was 93–118% and 8.9%, respectively. The absolute recoveries were 85±6% and 81±9% for [D-Trp]CJ-15,208 and the internal standard, respectively. The analytical method had excellent sensitivity with a lower limit of quantification of 0.5 ng/mL using a sample volume of 20 μL. The method was successfully applied to an initial pharmacokinetic study of [D-Trp]CJ-15,208 following intravenous administration to mice. PMID:27318293

Effects of terbinafine and itraconazole on the pharmacokinetics of orally administered tramadol.

PubMed

Saarikoski, Tuukka; Saari, Teijo I; Hagelberg, Nora M; Backman, Janne T; Neuvonen, Pertti J; Scheinin, Mika; Olkkola, Klaus T; Laine, Kari

2015-03-01

Tramadol is widely used for acute, chronic, and neuropathic pain. Its primary active metabolite is O-desmethyltramadol (M1), which is mainly accountable for the μ-opioid receptor-related analgesic effect. Tramadol is metabolized to M1 mainly by cytochrome P450 (CYP)2D6 enzyme and to other metabolites by CYP3A4 and CYP2B6. We investigated the possible interaction of tramadol with the antifungal agents terbinafine (CYP2D6 inhibitor) and itraconazole (CYP3A4 inhibitor). We used a randomized placebo-controlled crossover study design with 12 healthy subjects, of which 8 were extensive and 4 were ultrarapid CYP2D6 metabolizers. On the pretreatment day 4 with terbinafine (250 mg once daily), itraconazole (200 mg once daily) or placebo, subjects were given tramadol 50 mg orally. Plasma concentrations of tramadol and M1 were determined over 48 h and some pharmacodynamic effects over 12 h. Pharmacokinetic variables were calculated using standard non-compartmental methods. Terbinafine increased the area under plasma concentration-time curve (AUC0-∞) of tramadol by 115 % and decreased the AUC0-∞ of M1 by 64 % (P < 0.001). Terbinafine increased the peak concentration (C max) of tramadol by 53 % (P < 0.001) and decreased the C max of M1 by 79 % (P < 0.001). After terbinafine pretreatment the elimination half-life of tramadol and M1 were increased by 48 and 50 %, respectively (P < 0.001). Terbinafine reduced subjective drug effect of tramadol (P < 0.001). Itraconazole had minor effects on tramadol pharmacokinetics. Terbinafine may reduce the opioid effect of tramadol and increase the risk of its monoaminergic adverse effects. Itraconazole has no meaningful interaction with tramadol in subjects who have functional CYP2D6 enzyme.

Cannabidiol regulates behavioural alterations and gene expression changes induced by spontaneous cannabinoid withdrawal.

PubMed

Navarrete, Francisco; Aracil-Fernández, Auxiliadora; Manzanares, Jorge

2018-07-01

Cannabidiol (CBD) represents a promising therapeutic tool for treating cannabis use disorder (CUD). This study aimed to evaluate the effects of CBD on the behavioural and gene expression alterations induced by spontaneous cannabinoid withdrawal. Spontaneous cannabinoid withdrawal was evaluated 12 h after cessation of CP-55,940 treatment (0.5 mg·kg -1 every 12 h, i.p.; 7 days) in C57BL/6J mice. The effects of CBD (5, 10 and 20 mg·kg -1 , i.p.) on withdrawal-related behavioural signs were evaluated by measuring motor activity, somatic signs and anxiety-like behaviour. Furthermore, gene expression changes in TH in the ventral tegmental area, and in the opioid μ receptor (Oprm1), cannabinoid CB 1 receptor (Cnr1) and CB 2 receptor (Cnr2) in the nucleus accumbens, were also evaluated using the real-time PCR technique. The administration of CBD significantly blocked the increase in motor activity and the increased number of rearings, rubbings and jumpings associated with cannabinoid withdrawal, and it normalized the decrease in the number of groomings. However, CBD did not change somatic signs in vehicle-treated animals. In addition, the anxiogenic-like effect observed in abstinent mice disappeared with CBD administration, whereas CBD induced an anxiolytic-like effect in non-abstinent animals. Moreover, CBD normalized gene expression changes induced by CP-55,940-mediated spontaneous withdrawal. The results suggest that CBD alleviates spontaneous cannabinoid withdrawal and normalizes associated gene expression changes. Future studies are needed to determine the relevance of CBD as a potential therapeutic tool for treating CUD. © 2018 The British Pharmacological Society.

Morphine Pharmacokinetics in Children With Down Syndrome Following Cardiac Surgery.

PubMed

Goot, Benjamin H; Kaufman, Jon; Pan, Zhaoxing; Bourne, David W A; Hickey, Francis; Twite, Mark; Galinkin, Jeffrey; Christians, Uwe; Zuk, Jeannie; da Cruz, Eduardo M

2018-05-01

To assess if morphine pharmacokinetics are different in children with Down syndrome when compared with children without Down syndrome. Prospective single-center study including subjects with Down syndrome undergoing cardiac surgery (neonate to 18 yr old) matched by age and cardiac lesion with non-Down syndrome controls. Subjects were placed on a postoperative morphine infusion that was adjusted as clinically necessary, and blood was sampled to measure morphine and its metabolites concentrations. Morphine bolus dosing was used as needed, and total dose was tracked. Infusions were continued for 24 hours or until patients were extubated, whichever came first. Postinfusion, blood samples were continued for 24 hours for further evaluation of kinetics. If patients continued to require opioid, a nonmorphine alternative was used. Morphine concentrations were determined using a unique validated liquid chromatography tandem-mass spectrometry assay using dried blood spotting as opposed to large whole blood samples. Morphine concentration versus time data was modeled using population pharmacokinetics. A 16-bed cardiac ICU at an university-affiliated hospital. Forty-two patients (20 Down syndrome, 22 controls) were enrolled. None. The pharmacokinetics of morphine in pediatric patients with and without Down syndrome following cardiac surgery were analyzed. No significant difference was found in the patient characteristics or variables assessed including morphine total dose or time on infusion. Time mechanically ventilated was longer in children with Down syndrome, and regarding morphine pharmacokinetics, the covariates analyzed were age, weight, presence of Down syndrome, and gender. Only age was found to be significant. This study did not detect a significant difference in morphine pharmacokinetics between Down syndrome and non-Down syndrome children with congenital heart disease.

Pharmacokinetics of the injectable formulation of methadone hydrochloride administered orally in horses.

PubMed

Linardi, R L; Stokes, A M; Barker, S A; Short, C; Hosgood, G; Natalini, C C

2009-10-01

Methadone hydrochloride is a synthetic mu-opioid receptor agonist with potent analgesic properties. Oral methadone has been successfully used in human medicine and may overcome some limitations of other analgesics in equine species for producing analgesia with minimal adverse effects. However, there are no studies describing the pharmacokinetics (PK) of oral opioids in horses. The aim of this study was to describe the PK of orally administered methadone (0.1, 0.2 and 0.4 mg/kg) and physical effects in 12 healthy adult horses. Serum methadone concentrations were measured by gas chromatography/mass spectrometry at predetermined time points for 24 h, and PK parameters were estimated using a noncompartmental model. Physical effects were observed and recorded by experienced clinicians. No drug toxicity, behavioural or adverse effects were observed in the horses. The disposition of methadone followed first order elimination and a biphasic serum profile with rapid absorption and elimination phases. The PK profile of methadone was characterized by high clearance (Cl/F), small volume of distribution (V(d)/F) and short elimination half-life (t(1/2)). The mean of the estimated t(1/2) (SD) for each dose (0.1, 0.2 and 0.4 mg/kg) was 2.2 (35.6), 1.3 (46.1) and 1.5 (40.8), and the mean for the estimated C(max) (SD) was 33.9 (6.7), 127.9 (36.0) and 193.5 (65.8) respectively.

Intranasal Pharmacokinetics of Morphine ARER, a Novel Abuse-Deterrent Formulation: Results from a Randomized, Double-Blind, Four-Way Crossover Study in Nondependent, Opioid-Experienced Subjects

PubMed Central

Pantaleon, Carmela; Iverson, Matthew; Smith, Michael D.; Kinzler, Eric R.; Aigner, Stefan

2018-01-01

Objective To investigate the pharmacokinetics (PK) of Morphine ARER, an extended-release (ER), abuse-deterrent formulation of morphine sulfate after oral and intranasal administration. Methods This randomized, double-blind, double-dummy, placebo-controlled, four-way crossover study assessed the PK of morphine and its active metabolite, M6G, from crushed intranasal Morphine ARER and intact oral Morphine ARER compared with crushed intranasal ER morphine following administration to nondependent, recreational opioid users. The correlation between morphine PK and the pharmacodynamic parameter of drug liking, a measure of abuse potential, was also evaluated. Results Mean maximum observed plasma concentration (Cmax) for morphine was lower with crushed intranasal Morphine ARER (26.2 ng/mL) and intact oral Morphine ARER (18.6 ng/mL), compared with crushed intranasal ER morphine (49.5 ng/mL). The time to Cmax (Tmax) was the same for intact oral and crushed intranasal Morphine ARER (1.6 hours) and longer for crushed intranasal morphine ER (1.1 hours). Higher mean maximum morphine Cmax, Tmax, and abuse quotient (Cmax/Tmax) were positively correlated with maximum effect for drug liking (R2 ≥ 0.9795). Conclusion These data suggest that Morphine ARER maintains its ER profile despite physical manipulation and intranasal administration, which may be predictive of a lower intranasal abuse potential compared with ER morphine.

Tumor Targeting and Pharmacokinetics of a Near-Infrared Fluorescent-Labeled δ-Opioid Receptor Antagonist Agent, Dmt-Tic-Cy5.

PubMed

Huynh, Amanda Shanks; Estrella, Veronica; Stark, Valerie E; Cohen, Allison S; Chen, Tingan; Casagni, Todd J; Josan, Jatinder S; Lloyd, Mark C; Johnson, Joseph; Kim, Jongphil; Hruby, Victor J; Vagner, Josef; Morse, David L

2016-02-01

Fluorescence molecular imaging can be employed for the development of novel cancer targeting agents. Herein, we investigated the pharmacokinetics (PK) and cellular uptake of Dmt-Tic-Cy5, a delta-opioid receptor (δOR) antagonist-fluorescent dye conjugate, as a tumor-targeting molecular imaging agent. δOR expression is observed normally in the CNS, and pathologically in some tumors, including lung liver and breast cancers. In vitro, in vivo, and ex vivo experiments were conducted to image and quantify the fluorescence signal associated with Dmt-Tic-Cy5 over time using in vitro and intravital fluorescence microscopy and small animal fluorescence imaging of tumor-bearing mice. We observed specific retention of Dmt-Tic-Cy5 in tumors with maximum uptake in δOR-expressing positive tumors at 3 h and observable persistence for >96 h; clearance from δOR nonexpressing negative tumors by 6 h; and systemic clearance from normal organs by 24 h. Live-cell and intravital fluorescence microscopy demonstrated that Dmt-Tic-Cy5 had sustained cell-surface binding lasting at least 24 h with gradual internalization over the initial 6 h following administration. Dmt-Tic-Cy5 is a δOR-targeted agent that exhibits long-lasting and specific signal in δOR-expressing tumors, is rapidly cleared from systemic circulation, and is not retained in non-δOR-expressing tissues. Hence, Dmt-Tic-Cy5 has potential as a fluorescent tumor imaging agent.

Natural products in medicine: transformational outcome of synthetic chemistry.

PubMed

Szychowski, Janek; Truchon, Jean-François; Bennani, Youssef L

2014-11-26

This review brings to the forefront key synthetic modifications on natural products (NPs) that have yielded successful drugs. The emphasis is placed on the power of targeted chemical transformations in enhancing the therapeutic value of NPs through optimization of pharmacokinetics, stability, potency, and/or selectivity. Multiple classes of NPs such as macrolides, opioids, steroids, and β-lactams used to treat a variety of conditions such as cancers, infections, inflammation are exemplified. Molecular modeling or X-ray structures of NP/protein complexes supporting the observed boost in therapeutic value of the modified NPs are also discussed. Significant advancement in synthetic chemistry, in structure determination, and in the understanding of factors controlling pharmacokinetics can now better position drug discovery teams to undertake NPs as valuable leads. We hope that the beneficial NPs synthetic modifications outlined here will reignite medicinal chemists' interest in NPs and their derivatives.

Safety of Reiki Therapy for Newborns at Risk for Neonatal Abstinence Syndrome

PubMed Central

Wright-Esber, Sandra; Zupancic, Julie; Gargiulo, Deb; Woodall, Patricia

2018-01-01

The incidence of opioid abuse and subsequent drug withdrawal is exponentially on the rise in the United States for many populations including newborns who are born to drug-addicted mothers. These newborns often exhibit symptoms of neonatal abstinence syndrome (NAS) within 24 to 72 hours of birth. Treatment of NAS includes monitoring of withdrawal symptoms, managing physiological parameters, and the use of supportive and pharmacologic treatments. Although a few randomized controlled trials exist, studies on supportive intervention are generally limited by small sample sizes, case study reports, expert opinions, and descriptive design. Few studies address the safety of Reiki for newborns at risk for NAS using neonatal parameters. This pilot study addresses feasibility and demonstrates that Reiki is safe when administered to this high-risk population. Considerations for future studies are discussed. PMID:29315084

New opioid receptor antagonist: Naltrexone-14-O-sulfate synthesis and pharmacology.

PubMed

Zádor, Ferenc; Király, Kornél; Váradi, András; Balogh, Mihály; Fehér, Ágnes; Kocsis, Dóra; Erdei, Anna I; Lackó, Erzsébet; Zádori, Zoltán S; Hosztafi, Sándor; Noszál, Béla; Riba, Pál; Benyhe, Sándor; Fürst, Susanna; Al-Khrasani, Mahmoud

2017-08-15

Opioid antagonists, naloxone and naltrexone have long been used in clinical practice and research. In addition to their low selectivity, they easily pass through the blood-brain barrier. Quaternization of the amine group in these molecules, (e.g. methylnaltrexone) results in negligible CNS penetration. In addition, zwitterionic compounds have been reported to have limited CNS access. The current study, for the first time gives report on the synthesis and the in vitro [competition binding, G-protein activation, isolated mouse vas deferens (MVD) and mouse colon assay] pharmacology of the zwitterionic compound, naltrexone-14-O-sulfate. Naltrexone, naloxone, and its 14-O-sulfate analogue were used as reference compounds. In competition binding assays, naltrexone-14-O-sulfate showed lower affinity for µ, δ or κ opioid receptor than the parent molecule, naltrexone. However, the μ/κ opioid receptor selectivity ratio significantly improved, indicating better selectivity. Similar tendency was observed for naloxone-14-O-sulfate when compared to naloxone. Naltrexone-14-O-sulfate failed to activate [ 35 S]GTPγS-binding but inhibit the activation evoked by opioid agonists (DAMGO, Ile 5,6 deltorphin II and U69593), similarly to the reference compounds. Schild plot constructed in MVD revealed that naltrexone-14-O-sulfate acts as a competitive antagonist. In mouse colon, naltrexone-14-O-sulfate antagonized the inhibitory effect of morphine with lower affinity compared to naltrexone and higher affinity when compared to naloxone or naloxone-14-O-sulfate. In vivo (mouse tail-flick test), subcutaneously injected naltrexone-14-O-sulfate antagonized morphine's antinociception in a dose-dependent manner, indicating it's CNS penetration, which was unexpected from such zwitter ionic structure. Future studies are needed to evaluate it's pharmacokinetic profile. Copyright © 2017 Elsevier B.V. All rights reserved.

Neuropeptide systems and new treatments for nicotine addiction

PubMed Central

Bruijnzeel, Adriaan W.

2017-01-01

RATIONALE The mildly euphoric and cognitive enhancing effects of nicotine play a role in the initiation of smoking, while dysphoria and anxiety associated with smoking cessation contribute to relapse. After the acute withdrawal phase, smoking cues, a few cigarettes (i.e., lapse), and stressors can cause relapse. Human and animal studies have shown that neuropeptides play a critical role in nicotine addiction. OBJECTIVES The goal of this paper is to describe the role of neuropeptide systems in the initiation of nicotine intake, nicotine withdrawal, and the reinstatement of extinguished nicotine seeking. RESULTS The reviewed studies indicate that several drugs that target neuropeptide systems diminish the rewarding effects of nicotine by preventing the activation of dopaminergic systems. Other peptide-based drugs diminish the hyperactivity of brain stress systems and diminish withdrawal-associated symptom severity. Blockade of hypocretin-1 and nociceptin receptors and stimulation of galanin and neurotensin receptors diminishes the rewarding effects of nicotine. Both corticotropin-releasing factor type 1 and kappa-opioid receptor antagonists diminish dysphoria and anxiety-like behavior associated with nicotine withdrawal and inhibit stress-induced reinstatement of nicotine seeking. Furthermore, blockade of vasopressin 1b receptors diminishes dysphoria during nicotine withdrawal and melanocortin 4 receptor blockade prevents stress-induced reinstatement of nicotine seeking. The role of neuropeptide systems in nicotine-primed and cue-induced reinstatement is largely unexplored, but there is evidence for a role of hypocretin-1 receptors in cue-induced reinstatement of nicotine seeking. CONCLUSION Drugs that target neuropeptide systems might decrease the euphoric effects of smoking and improve relapse rates by diminishing withdrawal symptoms and improving stress resilience. PMID:28028605

Endomorphin analogues containing D-Pro2 discriminate different μ-opioid receptor mediated antinociception in mice

PubMed Central

Sakurada, Shinobu; Watanabe, Hiroyuki; Hayashi, Takafumi; Yuhki, Masayuki; Fujimura, Tsutomu; Murayama, Kimie; Sakurada, Chikai; Sakurada, Tsukasa

2002-01-01

The antagonistic actions of D-Pro2-endomorphins on inhibition of the paw withdrawal response by endomorphins were studied in mice. D-Pro2-endomorphin-1 and D-Pro2-endomorphin-2, injected intrathecally (i.t.), had no significant effect on the nociceptive thermal threshold alone. When D-Pro2-endomorphin-1 (0.05–0.1 pmol) was injected simultaneously with i.t. endomorphin-1 (5.0 nmol) or endomorphin-2 (5.0 nmol), antinociception induced by endomoprhin-1 was reduced significantly, whereas endomorphin-2-induced antinociception was not affected by D-Pro2-endomorphin-1. Antinociception induced by i.t. endomorphin-2 (5.0 nmol) was reduced significantly by its analogue, D-Pro2-endomorphin-2 (100 pmol), but not by D-Pro2-endomorphin-1. D-Pro2-endomorphin-1. D-Pro2-endomorphin-1 also antagonized the antinociceptive effect of i.t. DAMGO, a μ-opioid receptor agonist, whereas D-Pro2-endomorphin-2 failed to reduce the effect of DAMGO. These results suggest that endomorphin analogues containing D-Pro2 are able to discriminate the antinociceptive actions of μ1- and μ2-opioid receptor agonists at the spinal cord level. PMID:12466222

Differential analgesic effects of a mu-opioid peptide, [Dmt(1)]DALDA, and morphine.

PubMed

Shimoyama, Megumi; Szeto, Hazel H; Schiller, Peter W; Tagaito, Yugo; Tokairin, Hideyuki; Eun, Chong moon; Shimoyama, Naohito

2009-01-01

H-Dmt-D-Arg-Phe-Lys-NH(2) ([Dmt(1)]DALDA), a highly selective micro-opioid peptide, is potently analgesic after systemic and intrathecal administration but is less potent given intracerebroventricularly. This study was performed to further characterize the analgesic effects of [Dmt(1)]DALDA. We compared the effects of [Dmt(1)]DALDA and morphine after systemic administration in two different acute pain tests, the tail flick test and the paw withdrawal test, and examined how antagonizing the spinal opioid actions would affect their analgesic effects. [Dmt(1)]DALDA was markedly more potent in the tail flick test than in the hot plate test, while the potencies of morphine were similar in the two tests. Intrathecal naloxone completely blocked the effect of systemic [Dmt(1)]DALDA in the tail flick test, while it only partially blocked the effect of morphine. At higher doses that produced analgesia in the hot plate test, the effect of [Dmt(1)]DALDA in this test was only partially blocked by naloxone. Systemic [Dmt(1)]DALDA has a unique analgesic property clearly different from that of morphine and it has a propensity to produce spinal analgesia.

A Control Theory Model of Smoking

PubMed Central

Bobashev, Georgiy; Holloway, John; Solano, Eric; Gutkin, Boris

2017-01-01

We present a heuristic control theory model that describes smoking under restricted and unrestricted access to cigarettes. The model is based on the allostasis theory and uses a formal representation of a multiscale opponent process. The model simulates smoking behavior of an individual and produces both short-term (“loading up” after not smoking for a while) and long-term smoking patterns (e.g., gradual transition from a few cigarettes to one pack a day). By introducing a formal representation of withdrawal- and craving-like processes, the model produces gradual increases over time in withdrawal- and craving-like signals associated with abstinence and shows that after 3 months of abstinence, craving disappears. The model was programmed as a computer application allowing users to select simulation scenarios. The application links images of brain regions that are activated during the binge/intoxication, withdrawal, or craving with corresponding simulated states. The model was calibrated to represent smoking patterns described in peer-reviewed literature; however, it is generic enough to be adapted to other drugs, including cocaine and opioids. Although the model does not mechanistically describe specific neurobiological processes, it can be useful in prevention and treatment practices as an illustration of drug-using behaviors and expected dynamics of withdrawal and craving during abstinence. PMID:28868531

Low dose naltrexone administration in morphine dependent rats attenuates withdrawal-induced norepinephrine efflux in forebrain.

PubMed

Van Bockstaele, Elisabeth J; Qian, Yaping; Sterling, Robert C; Page, Michelle E

2008-05-15

The administration of low dose opioid antagonists has been explored as a potential means of detoxification in opiate dependence. Previous results from our laboratory have shown that concurrent administration of low dose naltrexone in the drinking water of rats implanted with subcutaneous morphine pellets attenuates behavioral and biochemical signs of withdrawal in brainstem noradrenergic nuclei. Noradrenergic projections originating from the nucleus tractus solitarius (NTS) and the locus coeruleus (LC) have previously been shown to be important neural substrates involved in the somatic expression of opiate withdrawal. The hypothesis that low dose naltrexone treatment attenuates noradrenergic hyperactivity typically associated with opiate withdrawal was examined in the present study by assessing norepinephrine tissue content and norepinephrine efflux using in vivo microdialysis coupled to high performance liquid chromatography (HPLC) with electrochemical detection (ED). The frontal cortex (FC), amygdala, bed nucleus of the stria terminalis (BNST) and cerebellum were analyzed for tissue content of norepinephrine following withdrawal in morphine dependent rats. Naltrexone-precipitated withdrawal elicited a significant decrease in tissue content of norepinephrine in the BNST and amygdala. This decrease was significantly attenuated in the BNST of rats that received low dose naltrexone pre-treatment compared to controls. No significant difference was observed in the other brain regions examined. In a separate group of rats, norepinephrine efflux was assessed with in vivo microdialysis in the BNST or the FC of morphine dependent rats or placebo treated rats subjected to naltrexone-precipitated withdrawal that received either naltrexone in their drinking water (5 mg/L) or unadulterated water. Following baseline dialysate collection, withdrawal was precipitated by injection of naltrexone and sample collection continued for an additional 4 h. At the end of the experiment, animals were transcardially perfused and the brains were removed for verification of probe placement. Low dose naltrexone pre-treatment significantly attenuated withdrawal-induced increases of extracellular norepinephrine in the BNST, with a smaller effect in the FC. These findings suggest that alterations in norepinephrine release associated with withdrawal may be attenuated in forebrain targets of noradrenergic brainstem neurons that may underlie reduced behavioral signs of withdrawal following low dose naltrexone administration.

Nebulized naloxone gently and effectively reverses methadone intoxication.

PubMed

Mycyk, Mark B; Szyszko, Amy L; Aks, Steven E

2003-02-01

A 46-year-old woman presented to the Emergency Department with lethargy and respiratory depression after ingesting methadone. Initial oxygen saturation of 61% on room air did not improve with supplemental oxygenation. As venous access was initially unobtainable, naloxone was administered by nebulizer. Within 5 min oxygen saturation was 100% and mental status was normal. The patient did not develop severe withdrawal symptoms. Naloxone hydrochloride has been administered by various routes to treat opioid toxicity. Our report describes the successful use of nebulized naloxone for methadone toxicity.

Short-Term Sleep Disturbance-Induced Stress Does not Affect Basal Pain Perception, but Does Delay Postsurgical Pain Recovery.

PubMed

Wang, Po-Kai; Cao, Jing; Wang, Hongzhen; Liang, Lingli; Zhang, Jun; Lutz, Brianna Marie; Shieh, Kun-Ruey; Bekker, Alex; Tao, Yuan-Xiang

2015-11-01

Chronic sleep disturbance-induced stress is known to increase basal pain sensitivity. However, most surgical patients frequently report short-term sleep disturbance/deprivation during the pre- and postoperation periods and have normal pain perception presurgery. Whether this short-term sleep disturbance affects postsurgical pain is elusive. Here, we report that pre- or postexposure to rapid eye movement sleep disturbance (REMSD) for 6 hours daily for 3 consecutive days did not alter basal responses to mechanical, heat, and cold stimuli, but did delay recovery in incision-induced reductions in paw withdrawal threshold to mechanical stimulation and paw withdrawal latencies to heat and cold stimuli on the ipsilateral side of male or female rats. This short-term REMSD led to stress shown by an increase in swim immobility time, a decrease in sucrose consumption, and an increase in the level of corticosterone in serum. Blocking this stress via intrathecal RU38486 or bilateral adrenalectomy abolished REMSD-caused delay in recovery of incision-induced reductions in behavioral responses to mechanical, heat, and cold stimuli. Moreover, this short-term REMSD produced significant reductions in the levels of mu opioid receptor and kappa opioid receptor, but not Kv1.2, in the ipsilateral L4/5 spinal cord and dorsal root ganglia on day 9 after incision (but not after sham surgery). Our findings show that short-term sleep disturbance either pre- or postsurgery does not alter basal pain perception, but does exacerbate postsurgical pain hypersensitivity. The latter may be related to the reductions of mu and kappa opioid receptors in the spinal cord and dorsal root ganglia caused by REMSD plus incision. Prevention of short-term sleep disturbance may help recovery from postsurgical pain in patients. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

Evaluation of buprenorphine dosage adequacy in opioid receptor agonist substitution therapy for heroin dependence: first use of the BUprenorphine-naloxone Dosage Adequacy eVAluation (BUDAVA) questionnaire.

PubMed

D'Amore, Antonio; Romano, Filomena; Biancolillo, Vincenzo; Lauro, Guglielmo; Armenante, Ciro; Pizzirusso, Anna; Del Tufo, Salvatore; Ruoppolo, Ciro; Auriemma, Francesco; Cassese, Francesco; Oliva, Patrizia; Amato, Patrizia

2012-07-01

The dosing of opioid receptor agonist medications adequately and on an individual basis is crucial in the pharmacotherapy of opioid dependence. Clinical tools that are able to measure dose appropriateness are sorely needed. The recently developed and validated Opiate Dosage Adequacy Scale (ODAS) comprehensively evaluates the main outcomes relevant for methadone dose optimization, namely relapse, cross-tolerance, objective and subjective withdrawal symptoms, craving and overdose. Based on the ODAS, we developed a new assessment tool (BUprenorphine-naloxone Dosage Adequacy eVAluation [BUDAVA]) for evaluating dosage adequacy in patients in treatment with buprenorphine-naloxone. The main goal of this observational study was to explore whether the BUDAVA questionnaire could be used to assess buprenorphine-based, long-term substitution therapy for heroin addiction. The study included heroin-dependent patients who had been in treatment with buprenorphine-naloxone for at least 3 months. Patients (n = 196) were recruited from 11 drug abuse treatment centres in Italy. Dosage adequacy was assessed with the BUDAVA questionnaire. Patients classified as inadequately treated had their dosage modified. After 1 week, they were again administered the questionnaire to assess the adequacy of the new dosage. The buprenorphine-naloxone dosage was found to be inadequate in 61 of the 196 patients. In 13 patients, the treatment scored as inadequate only in the subjective withdrawal symptoms item of the questionnaire and therefore no dosage adjustment was made in the 2 weeks that have characterized this work. The remaining 48 inadequately treated patients had their dosage modified (42 dose increases and six dose decreases). After 1 week on the modified dosage, in 24 of these patients the new regimen was found by the assessment with the questionnaire to be adequate. These preliminary results suggest that the BUDAVA questionnaire may be useful for guiding buprenorphine-naloxone maintenance dose adjustments in heroin-dependent patients.

Novel orally available salvinorin A analog PR-38 inhibits gastrointestinal motility and reduces abdominal pain in mouse models mimicking irritable bowel syndrome.

PubMed

Sałaga, M; Polepally, P R; Sobczak, M; Grzywacz, D; Kamysz, W; Sibaev, A; Storr, M; Do Rego, J C; Zjawiony, J K; Fichna, J

2014-07-01

The opioid and cannabinoid systems play a crucial role in multiple physiological processes in the central nervous system and in the periphery. Selective opioid as well as cannabinoid (CB) receptor agonists exert a potent inhibitory action on gastrointestinal (GI) motility and pain. In this study, we examined (in vitro and in vivo) whether PR-38 (2-O-cinnamoylsalvinorin B), a novel analog of salvinorin A, can interact with both systems and demonstrate therapeutic effects. We used mouse models of hypermotility, diarrhea, and abdominal pain. We also assessed the influence of PR-38 on the central nervous system by measurement of motoric parameters and exploratory behaviors in mice. Subsequently, we investigated the pharmacokinetics of PR-38 in mouse blood samples after intraperitoneal and oral administration. PR-38 significantly inhibited mouse colonic motility in vitro and in vivo. Administration of PR-38 significantly prolonged the whole GI transit time, and this effect was mediated by µ- and κ-opioid receptors and the CB1 receptor. PR-38 reversed hypermotility and reduced pain in mouse models mimicking functional GI disorders. These data expand our understanding of the interactions between opioid and cannabinoid systems and their functions in the GI tract. We also provide a novel framework for the development of future potential treatments of functional GI disorders. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

Discovery of 5-substituted tetrahydronaphthalen-2yl-methyl with N-phenyl-N-(piperidin-4-yl)propionamide derivatives as potent opioid receptor ligands.

PubMed

Deekonda, Srinivas; Wugalter, Lauren; Kulkarni, Vinod; Rankin, David; Largent-Milnes, Tally M; Davis, Peg; Bassirirad, Neemah M; Lai, Josephine; Vanderah, Todd W; Porreca, Frank; Hruby, Victor J

2015-09-15

A new series of novel opioid ligands have been designed and synthesized based on the 4-anilidopiperidine scaffold containing a 5-substituted tetrahydronaphthalen-2yl)methyl group with different N-phenyl-N-(piperidin-4-yl)propionamide derivatives to study the biological effects of these substituents on μ and δ opioid receptor interactions. Recently our group reported novel 4-anilidopiperidine analogues, in which several aromatic ring-contained amino acids were conjugated with N-phenyl-N-(piperidin-4-yl)propionamide and examined their biological activities at the μ and δ opioid receptors. In continuation of our efforts in these novel 4-anilidopiperidine analogues, we took a peptidomimetic approach in the present design, in which we substituted aromatic amino acids with tetrahydronaphthalen-2yl methyl moiety with amino, amide and hydroxyl substitutions at the 5th position. In in vitro assays these ligands, showed very good binding affinity and highly selective toward the μ opioid receptor. Among these, the lead ligand 20 showed excellent binding affinity (2 nM) and 5000 fold selectivity toward the μ opioid receptor, as well as functional selectivity in GPI assays (55.20 ± 4.30 nM) and weak or no agonist activities in MVD assays. Based on the in vitro bioassay results the lead compound 20 was chosen for in vivo assessment for efficacy in naïve rats after intrathecal administration. Compound 20 was not significantly effective in alleviating acute pain. This discrepancy between high in vitro binding affinity, moderate in vitro activity, and low in vivo activity may reflect differences in pharmacodynamics (i.e., engaging signaling pathways) or pharmacokinetics (i.e., metabolic stability). In sum, our data suggest that further optimization of this compound 20 is required to enhance in vivo activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of transversus abdominis plane block for renal transplant recipients - A meta-analysis and trial sequential analysis of published studies.

PubMed

Singh, Preet Mohinder; Borle, Anuradha; Makkar, Jeetinder Kaur; Trisha, Aanjan; Sinha, Aashish

2018-01-01

Patients undergoing renal transplant (RT) have altered drug/opioid pharmacokinetics. Transversus abdominis plane (TAP) block in renal transplant recipients has been recently evaluated for analgesic and opioid-sparing potential by many trials. The studies comparing TAP-block to conventional analgesic regimens for RT were searched. Comparisons were made for total opioids consumed (as morphine-equivalents) during the first postoperative 24-h (primary objective), intraoperative, and immediate-postoperative period. Pain scores and postoperative nausea-vomiting (PONV) were also evaluated. Trial sequential analysis (TSA) was used to quantify the strength of analysis. Ten-trials with 258 and 237 patients in control and TAP-block group, respectively, were included. TAP-block decreased the 24-h (reported in 9-trials) opioid consumption by 14.61 ± 4.34 mg (reduction by 42.7%, random-effects, P < 0.001, I 2 = 97.82%). Sample size of the present analysis (472) was well past the required "information-size" variable (396) as per the TSA for a power of 85%. Intraoperative opioid consumption also decreased by 2.06 ± 0.63 mg (reduction of 27.8%) (random effects, P < 0.001, I 2 = 98.84%). Pain scores with TAP-block were significantly lower in both early and delayed postoperative phase. Odds ratio for PONV without TAP block was 1.99 ± 1.05 (Fixed-effects, P = 0.04, I 2 = 0%). Publication bias was likely (Egger's test, X-intercept=7.89, P < 0.05). TAP-block significantly lowers the intraoperative and cumulative postoperative 24-h opioid consumption in RT recipients. Persistent and better pain control is achieved when TAP-Block is used. Benefits of TAP block extend beyond the analgesic actions alone as it also decreases the 24-h incidence of postoperative nausea vomiting as well. The technique of the block needs standardization for RT recipients.

NOP Receptor Mediates Anti-analgesia Induced by Agonist-Antagonist Opioids

PubMed Central

Gear, Robert W.; Bogen, Oliver; Ferrari, Luiz F.; Green, Paul G.; Levine, Jon D.

2014-01-01

Clinical studies have shown that agonist-antagonist opioid analgesics that produce their analgesic effect via action on the kappa-opioid receptor, produce a delayed-onset anti-analgesia in men but not women, an effect blocked by co-administration of a low dose of naloxone. We now report the same time-dependent anti-analgesia and its underlying mechanism in an animal model. Using the Randall-Selitto paw-withdrawal assay in male rats, we found that nalbuphine, pentazocine, and butorphanol each produced analgesia during the first hour followed by anti-analgesia starting at ~90 minutes after administration in males but not females, closely mimicking its clinical effects. As observed in humans, co-administration of nalbuphine with naloxone in a dose ratio of 12.5:1 blocked anti-analgesia but not analgesia. Administration of the highly selective kappa-opioid receptor agonist U69,593 produced analgesia without subsequent anti-analgesia, and confirmed by the failure of the selective kappa antagonist nor-binaltorphimine to block nalbuphine-induced anti-analgesia, indicating that anti-analgesia is not mediated by kappa-opioid receptors. We therefore tested the role of other receptors in nalbuphine anti-analgesia. Nociceptin/orphanin FQ (NOP) and sigma-1 and sigma-2 receptors were chosen on the basis of their known anti-analgesic effects and receptor binding studies. The selective NOP receptor antagonists, JTC801, and J113397, but not the sigma receptor antagonist, BD 1047, antagonized nalbuphine anti-analgesia. Furthermore, the NOP receptor agonist NNC 63-0532 produced anti-analgesia with the same delay in onset observed with the three agonist-antagonists, but without producing preceding analgesia and this anti-analgesia was also blocked by naloxone. These results strongly support the suggestion that clinically used agonist-antagonists act at the NOP receptor to produce anti-analgesia. PMID:24188792

Action of Phα1β, a peptide from the venom of the spider Phoneutria nigriventer, on the analgesic and adverse effects caused by morphine in mice.

PubMed

Tonello, Raquel; Rigo, Flávia; Gewehr, Camila; Trevisan, Gabriela; Pereira, Elizete Maria Rita; Gomez, Marcus Vinicius; Ferreira, Juliano

2014-06-01

Opioids are standard therapy for the treatment of pain; however, adverse effects limit their use. Voltage-gated calcium channel blockers may be used to increase opioid analgesia, but their effect on opioid-induced side effects is little known. Thus, the goal of this study was to evaluate the action of the peptide Phα1β, a voltage-gated calcium channel blocker, on the antinociceptive and adverse effects produced by morphine in mice. A single administration of morphine (3-10 mg/kg) was able to reduce heat nociception as well as decrease gastrointestinal transit. The antinociception caused by a single injection of morphine was slightly increased by an intrathecal injection of Phα1β (30 pmol/site). Repeated treatment with morphine caused tolerance, hyperalgesia, withdrawal syndrome, and constipation, and the Phα1β (.1-30 pmol/site, intrathecal) was able to reverse these effects. Finally, the effects produced by the native form of Phα1β were fully mimicked by a recombinant version of this peptide. Taken together, these data show that Phα1β was effective in potentiating the analgesia caused by a single dose of morphine as well as in reducing tolerance and the adverse effects induced by repeated administration of morphine, indicating its potential use as an adjuvant drug in combination with opioids. This article presents preclinical evidence for a useful adjuvant drug in opioid treatment. Phα1β, a peptide calcium channel blocker, could be used not only to potentiate morphine analgesia but also to reduce the adverse effects caused by repeated administration of morphine. Copyright © 2014. Published by Elsevier Inc.

Chronic Neuropathic Pain in Mice Reduces μ-Opioid Receptor-Mediated G-protein Activity in the Thalamus

PubMed Central

Hoot, Michelle R.; Sim-Selley, Laura J.; Selley, Dana E.; Scoggins, Krista L.; Dewey, William L.

2011-01-01

Neuropathic pain is a debilitating condition that is often difficult to treat using conventional pharmacological interventions and the exact mechanisms involved in the establishment and maintenance of this type of chronic pain have yet to be fully elucidated. The present studies examined the effect of chronic nerve injury on μ-opioid receptors and receptor-mediated G-protein activity within the supraspinal brain regions involved in pain processing of mice. Chronic constriction injury (CCI) reduced paw withdrawal latency, which was maximal at 10 days post-injury. [d-Ala2,(N-Me)Phe4, Gly5-OH] enkephalin (DAMGO)-stimulated [35S]GTPγS binding was then conducted at this time point in membranes prepared from the rostral ACC (rACC), thalamus and periaqueductal grey (PAG) of CCI and sham-operated mice. Results showed reduced DAMGO-stimulated [35S]GTPγS binding in the thalamus and PAG of CCI mice, with no change in the rACC. In thalamus, this reduction was due to decreased maximal stimulation by DAMGO, with no difference in EC50 values. In PAG, however, DAMGO Emax values did not significantly differ between groups, possibly due to the small magnitude of the main effect. [3H]Naloxone binding in membranes of the thalamus showed no significant differences in Bmax values between CCI and sham-operated mice, indicating that the difference in G-protein activation did not result from differences in μ-opioid receptor levels. These results suggest that CCI induced a region-specific adaptation of μ-opioid receptor-mediated G-protein activity, with apparent desensitization of the μ-opioid receptor in the thalamus and PAG and could have implications for treatment of neuropathic pain. PMID:21762883

Sublingual Buprenorphine/Naloxone for Chronic Pain in At-Risk Patients: Development and Pilot Test of a Clinical Protocol

PubMed Central

Rosenblum, Andrew; Cruciani, Ricardo A.; Strain, Eric C; Cleland, Charles M.; Joseph, Herman; Magura, Stephen; Marsch, Lisa A; McNicholas, Laura F; Savage, Seddon R; Sundaram, Arun; Portenoy, Russell K.

2013-01-01

Objective Sublingual buprenorphine/naloxone (Bup/Nx) is approved for addiction treatment and may be useful for pain management, particularly in opioid-treated pain patients with nonadherence behaviors. The transition of opioid-treated pain patients to buprenorphine carries the risk of precipitated withdrawal and increased pain. This study convened pain and addiction specialists to develop and pilot a clinical protocol for safe transitioning to Bup/Nx. Design The protocol was revised three times based on outside expert review and pilot study observations. The pilot was conducted with a prospective cohort of 12 patients with moderate to severe chronic pain, who were receiving long-term opioid therapy with any full μ-agonist drug, and had exhibited one or more aberrant drug-related behaviors. Patients were followed up for 3 to 6 months with the expectation that they would experience few adverse events and report lower pain severity. Results The three patients on the highest baseline opioid dose (equivalent to 303–450 mg of oral morphine) and the three on the lowest doses (≤20 mg) had early adverse events (AEs) when switched to Bup/Nx and did not complete the trial. Of the remaining six, one withdrew due to AEs; one responded well, then withdrew; and four completed a three-month trial. A mixed effects model controlling for dropouts found that average and worst pain significantly decreased after the switch to Bup/Nx (both p < .01). Conclusion Based on this experience, the protocol recommends Bup/Nx for pain only when baseline opioid doses are within bounds that reduce AEs at transition and incorporates dose flexibility to further reduce risks. This protocol warrants further testing. PMID:23264315

Treatment for amphetamine withdrawal.

PubMed

Shoptaw, Steven J; Kao, Uyen; Heinzerling, Keith; Ling, Walter

2009-04-15

Few studies examined treatments for amphetamine withdrawal, although it is a common problem among amphetamine users. Its symptoms, in particular intense craving, may be a critical factor leading to relapse to amphetamine use. In clinical practice, medications for cocaine withdrawal are commonly used to manage amphetamine withdrawal although the pharmacodynamic and pharmacokinetic properties of these two illicit substances are different. To assess the effectiveness of pharmacological alone or in combination with psychosocial treatment for amphetamine withdrawals on discontinuation rates, global state, withdrawal symptoms, craving, and other outcomes. MEDLINE (1966 - 2008), CINAHL (1982 - 2008), PsycINFO (1806 - 2008), CENTRAL (Cochrane Library 2008 issue 2), references of obtained articles. All randomised controlled and clinical trials evaluating pharmacological and or psychosocial treatments (alone or combined) for people with amphetamine withdrawal symptoms. Two authors evaluated and extracted data independently. The data were extracted from intention-to-treat analyses. The Relative Risk (RR) with the 95% confidence interval (95% CI) was used to assess dichotomous outcomes. The Weighted Mean Difference (WMD) with 95% CI was used to assess continuous outcomes. Four randomised controlled trials (involving 125 participants) met the inclusion criteria for the review. Two studies found that amineptine significantly reduced discontinuation rates and improved overall clinical presentation, but did not reduce withdrawal symptoms or craving compared to placebo. The benefits of mirtazapine over placebo for reducing amphetamine withdrawal symptoms were not as clear. One study suggested that mirtazapine may reduce hyperarousal and anxiety symptoms associated with amphetamine withdrawal. A more recent study failed to find any benefit of mirtazapine over placebo on retention or on amphetamine withdrawal symptoms. No medication is effective for treatment of amphetamine withdrawal. Amineptine showed reduction in discontinuation rates and improvement in clinical presentation compared to placebo, but had no effect on reducing withdrawal symptoms or craving. In spite of these limited benefits, amineptine is not available for use due to concerns over abuse liability when using the drug. The benefits of mirtazapine as a withdrawal agent are less clear based on findings from two randomised controlled trials: one report showed improvements in amphetamine withdrawal symptoms over placebo; a second report showed no differences in withdrawal symptoms compared to placebo. Further potential treatment studies should examine medications that increase central nervous system activity involving dopamine, norepinephrine and/or serotonin neurotransmitters, including mirtazapine.

Marijuana Dependence: Not Just Smoke and Mirrors

PubMed Central

Ramesh, Divya; Schlosburg, Joel E.; Wiebelhaus, Jason M.; Lichtman, Aron H.

2012-01-01

Marijuana (Cannabis sativa) is the most commonly used illicit drug worldwide as well as in the Unites States. Prolonged use of marijuana or repeated administration of its primary psychoactive constituent, Δ9-tetrahydrocannabinol (THC), can lead to physical dependence in humans and laboratory animals. The changes that occur with repeated cannabis use include alterations in behavioral, physiological, and biochemical responses. A variety of withdrawal responses occur in cannabis-dependent individuals: anger, aggression, irritability, anxiety and nervousness, decreased appetite or weight loss, restlessness, and sleep difficulties with strange dreams. But the long half-life and other pharmacokinetic properties of THC result in delayed expression of withdrawal symptoms, and because of the lack of contiguity between drug cessation and withdrawal responses the latter are not readily recognized as a clinically relevant syndrome. Over the past 30 years, a substantial body of clinical and laboratory animal research has emerged supporting the assertion that chronic exposure to cannabinoids produces physical dependence and may contribute to drug maintenance in cannabis-dependent individuals. However, no medications are approved to treat cannabis dependence and withdrawal. In this review, we describe preclinical and clinical research that supports the existence of a cannabinoid withdrawal syndrome. In addition, we review research evaluating potential pharmacotherapies (e.g., THC, a variety of antidepressant drugs, and lithium) to reduce cannabis withdrawal responses and examine how expanded knowledge about the regulatory mechanisms in the endocannabinoid system may lead to promising new therapeutic targets. PMID:23382144

Sympathetic activity induced by naloxone-precipitated morphine withdrawal is blocked in genetically engineered mice lacking functional CRF1 receptor

DOE Office of Scientific and Technical Information (OSTI.GOV)

García-Carmona, Juan-Antonio; Martínez-Laorden, Elena; Milanés, María-Victoria

There is large body evidence indicating that stress can lead to cardiovascular disease. However, the exact brain areas and the mechanisms involved remain to be revealed. Here, we performed a series of experiments to characterize the role of CRF1 receptor (CRF1R) in the stress response induced by naloxone-precipitated morphine withdrawal. The experiments were performed in the hypothalamic paraventricular nucleus (PVN) ventrolateral medulla (VLM), brain regions involved in the regulation of cardiovascular activity, and in the right ventricle by using genetically engineered mice lacking functional CRF1R levels (KO). Mice were treated with increasing doses of morphine and withdrawal was precipitated bymore » naloxone administration. Noradrenaline (NA) turnover, c-Fos, expression, PKA and TH phosphorylated at serine 40, was evaluated by high-performance liquid chromatography (HPLC), immunohistochemistry and immunoblotting. Morphine withdrawal induced an enhancement of NA turnover in PVN in parallel with an increase in TH neurons expressing c-Fos in VLM in wild-type mice. In addition we have demonstrated an increase in NA turnover, TH phosphorylated at serine 40 and PKA levels in heart. The main finding of the present study was that NA turnover, TH positive neurons that express c-Fos, TH phosphorylated at serine 40 and PKA expression observed during morphine withdrawal were significantly inhibited in CRF1R KO mice. Our results demonstrate that CRF/CRF1R activation may contribute to the adaptive changes induced by naloxone-precipitated withdrawal in the heart and in the brain areas which modulate the cardiac sympathetic function and suggest that CRF/CRF1R pathways could be contributing to cardiovascular disease associated to opioid addiction. - Highlights: • Naloxone-precipitated morphine withdrawal increases sympathetic activity in the PVN and heart. • Co-localization of TH phosphorylated at serine 40/c-Fos in the VLM after morphine withdrawal • Naloxone-precipitated morphine withdrawal increases PKA expression in the heart. • CRF1 receptor is implicated in the sympathetic activity induced by morphine withdrawal.« less

Mu-opioid blockade reduces ethanol effects on intake and behavior of the infant rat during short-term but not long-term social isolation

PubMed Central

Kozlov, Andrey P.; Nizhnikov, Michael E.; Kramskaya, Tatiana. A.; Varlinskaya, Elena I.; Spear, Norman E.

2013-01-01

Numerous findings in adult and infant rats have shown that the endogenous opioid system is involved in control of ethanol consumption and its reinforcing effects. Opioid systems are also involved in reactivity to social isolation with several factors (age, duration, and type of isolation) affecting this modulation. The present study investigated the effects of a selective mu – opioid antagonist CTOP (0, 0.1, 0.5 mg/kg), ethanol (0, 0.5 g/kg), and the interaction of the two drugs on the behavioral consequences of two types of social isolation given to preweanling rats: 1) short–term social isolation from littermates (STSI, duration 8 minutes) and 2) relatively long-term (5 hours) isolation (LTSI) from the dam and littermates. Voluntary intake of saccharin, locomotion, rearing activity, paw licking, and grooming were assessed during an 8 – min. intake test. Thermal nociceptive reactivity was also measured before and after the testing session with normalized differences in pre- and post-test latencies of paw withdrawal from a hot plate (49 °C) used as an index of isolation-induced analgesia (IIA). The results indicate that pharmacological blockade of mu-opioid receptors by CTOP substantially attenuated ethanol’s anxiolytic effects on the developing rat’s reactions to social isolation. Some of these stress-attenuating effects of CTOP were observed only in animals exposed to short-term isolation (STSI) but not in pups isolated for 5 hours (LTSI). Ethanol selectively increased saccharin intake during STSI in females and CTOP blocked this effect. Ethanol decreased the magnitude of analgesia associated with STSI but had no effect on pain reactivity during LTSI. CTOP by itself did not affect IIA or saccharin intake in sober animals. The findings of the present experiments indicate that the anxiolytic effects of 0.5 g/kg ethanol on pups exposed to STSI are modulated by endogenous opioid activity. PMID:23182856

Identifying and treating codeine dependence: a systematic review.

PubMed

Nielsen, Suzanne; MacDonald, Tim; Johnson, Jacinta L

2018-06-04

Codeine dependence is a significant public health problem, motivating the recent rescheduling of codeine in Australia (1 February 2018). To provide information for informing clinical responses, we undertook a systematic review of what is known about identifying and treating codeine dependence. Articles published in English that described people who were codeine-dependent or a clinical approach to treating people who were codeine-dependent, without restriction on year of publication, were reviewed. Articles not including empirical data were excluded. One researcher screened each abstract; two researchers independently reviewed full text articles. Study quality was assessed, and data were extracted with standardised tools. MEDLINE and EMBASE were searched for relevant publications on 22 November 2016. The reference lists of eligible studies were searched to identify further relevant publications. 2150 articles were initially identified, of which 41 were eligible for inclusion in our analysis. Studies consistently reported specific characteristics associated with codeine dependence, including mental health comorbidity and escalation of codeine use attributed to psychiatric problems. Case reports and series described codeine dependence masked by complications associated with overusing simple analgesics and delayed detection. Ten studies described the treatment of codeine dependence. Three reports identified a role for behavioural therapy; the efficacy of CYP inhibitors in a small open label trial was not confirmed in a randomised controlled trial; four case series/chart reviews described opioid agonist therapy and medicated inpatient withdrawal; two qualitative studies identified barriers related to perceptions of codeine-dependent people and treatment providers, and confirmed positive perceptions and treatment outcomes achieved with opioid agonist treatments. Strategies for identifying problematic codeine use are needed. Identifying codeine dependence in clinical settings is often delayed, contributing to serious morbidity. Commonly described approaches for managing codeine dependence include opioid taper, opioid agonist treatment, and psychological therapies. These approaches are consistent with published evidence for pharmaceutical opioid dependence treatment and with broader frameworks for treating opioid dependence. PROSPERO registration: CRD42016052129.

Switch from excitatory to inhibitory actions of ethanol on dopamine levels after chronic exposure: Role of kappa opioid receptors

PubMed Central

Karkhanis, Anushree N.; Huggins, Kimberly N.; Rose, Jamie H.; Jones, Sara R.

2016-01-01

Acute ethanol exposure is known to stimulate the dopamine system; however, chronic exposure has been shown to downregulate the dopamine system. In rodents, chronic intermittent exposure (CIE) to ethanol also increases negative affect during withdrawal, such as, increases in anxiety- and depressive-like behavior. Moreover, CIE exposure results in increased ethanol drinking and preference during withdrawal. Previous literature documents reductions in CIE-induced anxiety-, depressive-like behaviors and ethanol intake in response to kappa opioid receptor (KOR) blockade. KORs are located on presynaptic dopamine terminals in the nucleus accumbens (NAc) and inhibit release, an effect which has been linked to negative affective behaviors. Previous reports show an upregulation in KOR function following extended CIE exposure; however it is not clear whether there is a direct link between KOR upregulation and dopamine downregulation during withdrawal from CIE. This study aimed to examine the effects of KOR modulation on dopamine responses to ethanol of behaving mice exposed to air or ethanol vapor in a repeated intermittent pattern. First, we showed that KORs have a greater response to an agonist after moderate CIE compared to air exposed mice using ex vivo fast scan cyclic voltammetry. Second, using in vivo microdialysis, we showed that, in contrast to the expected increase in extracellular levels of dopamine following an acute ethanol challenge in air exposed mice, CIE exposed mice exhibited a robust decrease in dopamine levels. Third, we showed that blockade of KORs reversed the aberrant inhibitory dopamine response to ethanol in CIE exposed mice while not affecting the air exposed mice demonstrating that inhibition of KORs “rescued” dopamine responses in CIE exposed mice. Taken together, these findings indicate that augmentation of dynorphin/KOR system activity drives the reduction in stimulated (electrical and ethanol) dopamine release in the NAc. Thus, blockade of KORs is a promising avenue for developing pharmacotherapies for alcoholism. PMID:27450094

A non-rewarding, non-aversive buprenorphine/naltrexone combination attenuates drug-primed reinstatement to cocaine and morphine in rats in a conditioned place preference paradigm.

PubMed

Cordery, Sarah F; Taverner, Alistair; Ridzwan, Irna E; Guy, Richard H; Delgado-Charro, M Begoña; Husbands, Stephen M; Bailey, Christopher P

2014-07-01

Concurrent use of cocaine and heroin is a major public health issue with no effective relapse prevention treatment currently available. To this purpose, a combination of buprenorphine and naltrexone, a mixed very-low efficacy mu-opioid receptor agonist/kappa-opioid receptor antagonist/nociceptin receptor agonist, was investigated. The tail-withdrawal and the conditioned place preference (CPP) assays in adult Sprague Dawley rats were used to show that naltrexone dose-dependently blocked the mu-opioid receptor agonism of buprenorphine. Furthermore, in the CPP assay, a combination of 0.3 mg/kg buprenorphine and 3.0 mg/kg naltrexone was aversive. A combination of 0.3 mg/kg buprenorphine and 1.0 mg/kg naltrexone was neither rewarding nor aversive, but still possessed mu-opioid receptor antagonist properties. In the CPP extinction and reinstatement method, a combination of 0.3 mg/kg buprenorphine and 1.0 mg/kg naltrexone completely blocked drug-primed reinstatement in cocaine-conditioned rats (conditioned with 3 mg/kg cocaine, drug prime was 3 mg/kg cocaine) and attenuated drug-primed reinstatement in morphine-conditioned rats (conditioned with 5 mg/kg morphine, drug prime was 1.25 mg/kg morphine). These data add to the growing evidence that a buprenorphine/naltrexone combination may be protective against relapse in a polydrug abuse situation. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

Ventrolateral orbital cortex oxytocin attenuates neuropathic pain through periaqueductal gray opioid receptor.

PubMed

Taati, Mina; Tamaddonfard, Esmaeal

2018-06-01

Oxytocin plays an important role in supraspinal modulation of pain. In the present study, we investigated the effects of ventrolateral orbital cortex (VLOC) microinjection of oxytocin on neuropathic pain after blockade of opioid receptors in this area and ventrolateral periaqueductal gray (vlPAG). Neuropathic pain was induced by complete transcection of preoneal and tibial branches of sciatic nerve. The VLOC and vlPAG were unilaterally (contralateral to the sciatic nerve-injured side) and bilaterally implanted with guide cannulas, respectively. Mechanical paw withdrawal threshold (PWT) was measured using von Frey filaments. Area under curve (AUC) was also calculated. Microinjection of oxytocin (5, 10 and 20 ng/site) into the VLOC increased PWT. Antiallodynia induced by oxytocin (20 ng/site) was inhibited by prior intra-VLOC administration of atosiban (an oxytocin receptor antagonist, 100 ng/site) and naloxone (an opioid receptor antagonist, 500 ng/site). Prior microinjection of naloxone (500 ng/site) into the vlPAG also inhibited antiallodynia induced by intra-VLOC microinjection of oxytocin (20 ng/site). All the VLOC and vlPAG microinjected drugs did not alter locomotor activity. It is concluded that oxytocin and its receptor may be involved in modulation of neuropathic pain at the VLOC level. Opioid receptors of VLOC and vlPAG might be involved in the antiallodynic effect of the VLOC-microinjected oxytocin. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Evaluation and comparison of antinociceptive activity of aspartame with sucrose.

PubMed

Rani, Seema; Gupta, Mahesh C

2012-01-01

Artificial sweeteners are low-calorie substances used to sweeten a wide variety of foods. At present they are used increasingly not only by diabetics, but also by the general public as a mean of controlling the weight. This study was carried out to evaluate and compare antinociceptive activity of the artificial sweeteners, aspartame and sucrose and to study the mechanisms involved in this analgesic activity. Forty eight white albino Wistar rats were divided into two groups of 24 rats each. Group 1 received sucrose and group 2 received aspartame solution ad libitum for 14 days as their only source of liquid. On 14(th) day, both groups of rats were divided into 3 subgroups having 8 rats each. Group Ia and IIa served as control. Group Ib and IIb were given naloxone and Ic and IIc received ketanserin, the opioid and serotonergic receptor antagonists, respectively. Tail withdrawal latencies (tail flick analgesiometer) and paw licking/jumping latencies (Eddy's hot plate method) were increased significantly in both aspartame and sucrose group. The analgesia produced by aspartame was comparable with sucrose. The opioid receptor antagonist naloxone and the 5-HT(2A/2C) serotonergic receptor antagonist ketanserin partly reversed the antinociceptive effect of these sweeteners. Thus, the artificial sweetening agent aspartame showed antinociceptive activity like sucrose in rats. Reduction in antinociceptive activity of aspartame and sucrose by opioid and serotoninergic antagonists demonstrate the involvement of both opioid and serotonergic system.

Interaction of the adenosine A1 receptor agonist N6-cyclopentyladenosine (CPA) and opioid receptors in spinal cord nociceptive reflexes.

PubMed

Ramos-Zepeda, Guillermo; Herrero, Juan F

2013-08-14

We previously observed that the adenosine A1 receptor agonist N6-cyclopentyladenosine (CPA) is a very effective antinociceptive agent on intact but not on spinalized adult rats with inflammation. Since a close connection between opioid and adenosine A1 receptors has been described, we studied a possible relationship between these systems in the spinal cord. CPA-mediated antinociception was challenged by the selective adenosine A1 receptor antagonist 8-cyclopentyl-1, 3-dimethylxanthine (CPT) and by the opioid receptor antagonist naloxone on male adult Wistar rats with carrageenan-induced inflammation. Withdrawal reflexes activated by noxious mechanical and electrical stimulation were recorded using the single motor technique in intact and sham-spinalized animals. CPA was very effective in intact and sham spinalized rats but not in spinalized animals. Full reversal of CPA antinociception was observed with i.v. 1mg/kg of naloxone but not with 20mg/kg of CPT i.v. in responses to noxious mechanical and electrical stimulation. CPT fully prevented CPA from any antinociceptive action whereas naloxone did not modify CPA activity. These results suggest a centrally-mediated action, since CPA depressed the wind-up phenomenon which is derived of the activity of spinal cord neurons. The present study provides strong in vivo evidence of an antinociceptive activity mediated by the adenosine A1 receptor system in the spinal cord, linked to an activation of opioid receptors in adult animals with inflammation. © 2013.

Effects of Menthol on Nicotine Pharmacokinetic, Pharmacology and Dependence in Mice.

PubMed

Alsharari, Shakir D; King, Justin R; Nordman, Jacob C; Muldoon, Pretal P; Jackson, Asti; Zhu, Andy Z X; Tyndale, Rachel F; Kabbani, Nadine; Damaj, M Imad

2015-01-01

Although menthol, a common flavoring additive to cigarettes, has been found to impact the addictive properties of nicotine cigarettes in smokers little is known about its pharmacological and molecular actions in the brain. Studies were undertaken to examine whether the systemic administration of menthol would modulate nicotine pharmacokinetics, acute pharmacological effects (antinociception and hypothermia) and withdrawal in male ICR mice. In addition, we examined changes in the brain levels of nicotinic receptors of rodents exposed to nicotine and menthol. Administration of i.p. menthol significantly decreased nicotine's clearance (2-fold decrease) and increased its AUC compared to i.p. vehicle treatment. In addition, menthol pretreatment prolonged the duration of nicotine-induced antinociception and hypothermia (2.5 mg/kg, s.c.) for periods up to 180 min post-nicotine administration. Repeated administration of menthol with nicotine increased the intensity of mecamylamine-precipitated withdrawal signs in mice exposed chronically to nicotine. The potentiation of withdrawal intensity by menthol was accompanied by a significant increase in nicotine plasma levels in these mice. Western blot analyses of α4 and β2 nAChR subunit expression suggests that chronic menthol impacts the levels and distribution of these nicotinic subunits in various brain regions. In particular, co-administration of menthol and nicotine appears to promote significant increase in β2 and α4 nAChR subunit expression in the hippocampus, prefrontal cortex and striatum of mice. Surprisingly, chronic injections of menthol alone to mice caused an upregulation of β2 and α4 nAChR subunit levels in these brain regions. Because the addition of menthol to tobacco products has been suggested to augment their addictive potential, the current findings reveal several new pharmacological molecular adaptations that may contribute to its unique addictive profile.

Effects of Menthol on Nicotine Pharmacokinetic, Pharmacology and Dependence in Mice

PubMed Central

Alsharari, Shakir D.; King, Justin R.; Nordman, Jacob C.; Muldoon, Pretal P.; Jackson, Asti; Zhu, Andy Z. X.; Tyndale, Rachel F.; Kabbani, Nadine; Damaj, M. Imad.

2015-01-01

Although menthol, a common flavoring additive to cigarettes, has been found to impact the addictive properties of nicotine cigarettes in smokers little is known about its pharmacological and molecular actions in the brain. Studies were undertaken to examine whether the systemic administration of menthol would modulate nicotine pharmacokinetics, acute pharmacological effects (antinociception and hypothermia) and withdrawal in male ICR mice. In addition, we examined changes in the brain levels of nicotinic receptors of rodents exposed to nicotine and menthol. Administration of i.p. menthol significantly decreased nicotine’s clearance (2-fold decrease) and increased its AUC compared to i.p. vehicle treatment. In addition, menthol pretreatment prolonged the duration of nicotine-induced antinociception and hypothermia (2.5 mg/kg, s.c.) for periods up to 180 min post-nicotine administration. Repeated administration of menthol with nicotine increased the intensity of mecamylamine-precipitated withdrawal signs in mice exposed chronically to nicotine. The potentiation of withdrawal intensity by menthol was accompanied by a significant increase in nicotine plasma levels in these mice. Western blot analyses of α4 and β2 nAChR subunit expression suggests that chronic menthol impacts the levels and distribution of these nicotinic subunits in various brain regions. In particular, co-administration of menthol and nicotine appears to promote significant increase in β2 and α4 nAChR subunit expression in the hippocampus, prefrontal cortex and striatum of mice. Surprisingly, chronic injections of menthol alone to mice caused an upregulation of β2 and α4 nAChR subunit levels in these brain regions. Because the addition of menthol to tobacco products has been suggested to augment their addictive potential, the current findings reveal several new pharmacological molecular adaptations that may contribute to its unique addictive profile. PMID:26355604

THERMAL SENSITIVITY ACROSS AGES AND DURING CHRONIC FENTANYL ADMINISTRATION IN RATS

PubMed Central

Mitzelfelt, Jeremiah D.; Carter, Christy S.; Morgan, Drake

2013-01-01

Rationale Chronic pain is becoming a more common medical diagnosis and is especially prevalent in older individuals. As such, prescribed use of opioids is on the rise, even though the efficacy for pain management in older individuals is unclear. Objectives Thus the present preclinical study assessed the effectiveness of chronic fentanyl administration to produce antinociception in aging rats (16, 20, 24 months). Methods Animals were tested in a thermal sensitivity procedure known to involve neural circuits implicated in chronic pain in humans. Sensitivity to heat and cold thermal stimulation was assessed during 28 days of fentanyl administration (1.0 mg/kg/day), and 28 days of withdrawal. Results Fentanyl resulted in decreased thermal sensitivity to heat but not cold stimulation indicated by more time spent in the hot compartment relative to time spent in the cold or neutral compartments. Unlike previous findings using a hot-water tail withdrawal procedure, tolerance did not develop to the antinociceptive effects of fentanyl over a 28-day period of drug administration. The oldest animals were least sensitive, and the youngest animals most sensitive to the locomotor-stimulating effects of fentanyl. The effect on the antinociceptive response to fentanyl in the oldest group of rats was difficult to interpret due to profound changes in the behavior of saline-treated animals. Conclusions Overall, aging modifies the behavioral effects of opioids, a finding that may inform future studies for devising appropriate treatment strategies. PMID:23900640

Targeting Dynorphin/Kappa Opioid Receptor Systems to Treat Alcohol Abuse and Dependence

PubMed Central

Walker, Brendan M.; Valdez, Glenn R.; McLaughlin, Jay P.; Bakalkin, Georgy

2012-01-01

This review represents the focus of a symposium that was presented at the “Alcoholism and Stress: A Framework for Future Treatment Strategies” conference in Volterra, Italy on May 3–6, 2011 and organized / chaired by Dr. Brendan M. Walker. The primary goal of the symposium was to evaluate and disseminate contemporary findings regarding the emerging role of kappa-opioid receptors (KORs) and their endogenous ligands dynorphins (DYNs) in the regulation of escalated alcohol consumption, negative affect and cognitive dysfunction associated with alcohol dependence, as well as DYN / KOR mediation of the effects of chronic stress on alcohol reward and seeking behaviors. Dr. Glenn Valdez described a role for KORs in the anxiogenic effects of alcohol withdrawal. Dr. Jay McLaughlin focused on the role of KORs in repeated stress-induced potentiation of alcohol reward and increased alcohol consumption. Dr. Brendan Walker presented data characterizing the effects of KOR antagonism within the extended amygdala on withdrawal-induced escalation of alcohol self-administration in dependent animals. Dr. Georgy Bakalkin concluded with data indicative of altered DYNs and KORs in the prefrontal cortex of alcohol dependent humans that could underlie diminished cognitive performance. Collectively, the data presented within this symposium identified the multifaceted contribution of KORs to the characteristics of acute and chronic alcohol-induced behavioral dysregulation and provided a foundation for the development of pharmacotherapeutic strategies to treat certain aspects of alcohol use disorders. PMID:22459870

Opiate-induced Changes in Brain Adenosine Levels and Narcotic Drug Responses

PubMed Central

Wu, Manhong; Sahbaie, Peyman; Zheng, Ming; Lobato, Robert; Boison, Detlev; Clark, J. David; Peltz, Gary

2012-01-01

We have very little information about the metabolomic changes that mediate neurobehavioral responses, including addiction. It was possible that opioid-induced metabolomic changes in brain could mediate some of the pharmacodynamic effects of opioids. To investigate this, opiate-induced brain metabolomic responses were profiled using a semi-targeted method in C57BL/6 and 129Sv1 mice, which exhibit extreme differences in their tendency to become opiate dependent. Escalating morphine doses (10–40 mg/kg) administered over a 4-day period selectively induced a two-fold decrease (p<0.00005) in adenosine abundance in the brainstem of C57BL/6 mice, which exhibited symptoms of narcotic drug dependence; but did not decrease adenosine abundance in 129Sv1 mice, which do not exhibit symptoms of dependence. Based on this finding, the effect of adenosine on dependence was investigated in genetically engineered mice with alterations in adenosine tone in the brain and in pharmacologic experiments. Morphine withdrawal behaviors were significantly diminished (P<0.0004) in genetically engineered mice with reduced adenosine tone in the brainstem, and by treatment with an adenosine receptor1 (A1) agonist (2-chloro-N6-cyclopentyladenosine, 0.5 mg/kg) or an A2a receptor (A2a) antagonist (SCH 58261 1 mg/kg). These results indicate that adenosine homeostasis plays a crucial role in narcotic drug responses. Opiate-induced changes in brain adenosine levels may explain many important neurobehavioral features associated with opiate addiction and withdrawal. PMID:23098802

Pharmacological challenges in chronic pancreatitis.

PubMed

Olesen, Anne Estrup; Brokjaer, Anne; Fisher, Iben Wendelboe; Larsen, Isabelle Myriam

2013-11-14

Drug absorption in patients with chronic pancreatitis might be affected by the pathophysiology of the disease. The exocrine pancreatic insufficiency is associated with changes in gastrointestinal intraluminal pH, motility disorder, bacterial overgrowth and changed pancreatic gland secretion. Together these factors can result in malabsorption and may also affect the efficacy of pharmacological intervention. The lifestyle of chronic pancreatitis patients may also contribute to gastrointestinal changes. Many patients limit their food intake because of the pain caused by eating and in some cases food intake is more or less substituted with alcohol, tobacco and coffee. Alcohol and drug interaction are known to influence the pharmacokinetics by altering either drug absorption or by affecting liver metabolism. Since patients suffering from chronic pancreatitis experience severe pain, opioids are often prescribed as pain treatment. Opioids have intrinsic effects on gastrointestinal motility and hence can modify the absorption of other drugs taken at the same time. Furthermore, the increased fluid absorption caused by opioids will decrease water available for drug dissolution and may hereby affect absorption of the drug. As stated above many factors can influence drug absorption and metabolism in patients with chronic pancreatitis. The factors may not have clinical relevance, but may explain inter-individual variations in responses to a given drug, in patients with chronic pancreatitis.

The effect of exercise frequency on neuropathic pain and pain-related cellular reactions in the spinal cord and midbrain in a rat sciatic nerve injury model

PubMed Central

Sumizono, Megumi; Otsuka, Shotaro; Terashi, Takuto; Nakanishi, Kazuki; Ueda, Koki; Takada, Seiya; Kikuchi, Kiyoshi

2018-01-01

Background Exercise regimens are established methods that can relieve neuropathic pain. However, the relationship between frequency and intensity of exercise and multiple cellular responses of exercise-induced alleviation of neuropathic pain is still unclear. We examined the influence of exercise frequency on neuropathic pain and the intracellular responses in a sciatic nerve chronic constriction injury (CCI) model. Materials and methods Rats were assigned to four groups as follows: CCI and high-frequency exercise (HFE group), CCI and low-frequency exercise (LFE group), CCI and no exercise (No-Ex group), and naive animals (control group). Rats ran on a treadmill, at a speed of 20 m/min, for 30 min, for 5 (HFE) or 3 (LFE) days a week, for a total of 5 weeks. The 50% withdrawal threshold was evaluated for mechanical sensitivity. The activation of glial cells (microglia and astrocytes), expression of brain-derived neurotrophic factor (BDNF) and μ-opioid receptor in the spinal dorsal horn and endogenous opioid in the midbrain were examined using immunohistochemistry. Opioid receptor antagonists (naloxone) were administered using intraperitoneal injection. Results The development of neuropathic pain was related to the activation of glial cells, increased BDNF expression, and downregulation of the μ-opioid receptor in the ipsilateral spinal dorsal horn. In the No-Ex group, neuropathic pain showed the highest level of mechanical hypersensitivity at 2 weeks, which improved slightly until 5 weeks after CCI. In both exercise groups, the alleviation of neuropathic pain was accelerated through the regulation of glial activation, BDNF expression, and the endogenous opioid system. The expression of BDNF and endogenous opioid in relation to exercise-induced alleviation of neuropathic pain differed in the HFE and LFE groups. The effects of exercise-induced alleviation of mechanical hypersensitivity were reversed by the administration of naloxone. Conclusion The LFE and HFE program reduced neuropathic pain. Our findings indicated that aerobic exercise-induced alleviated neuropathic pain through the regulation of glial cell activation, expression of BDNF in the ipsilateral spinal dorsal horn, and the endogenous opioid system. PMID:29445295

Nature-inspired indolyl-2-azabicyclo[2.2.2]oct-7-ene derivatives as promising agents for the attenuation of withdrawal symptoms: synthesis of 20-desethyl-20-hydroxymethyl-11-demethoxyibogaine.

PubMed

Passarella, D; Barilli, A; Efange, S M N; Elisabetsky, E; Leal, M B; Lesma, G; Linck, V M; Mash, D C; Martinelli, M; Peretto, I; Silvani, A; Danieli, B

2006-07-10

Microwave assisted Diels-Alder cycloaddition of 5-Br-N-benzylpyridinone (2) with methyl acrylate is described to gain an easy access to 7-bromo-2-benzyl-3-oxo-2-aza-5 or 6-carbomethoxy bicyclo[2.2.2]oct-7-enes (3)-(6). The preparation of the ibogaine analogue 20-desethyl-(20-endo)-hydroxymethyl-11-demethoxyibogaine (17) is described by stereoselective hydrogenation of the C(7)-C(8) double bond. Biological evaluation showed an interesting in vitro binding profile toward dopamine transporter, serotonin transporter and opioid receptor systems accompanied by an antiwithdrawal effect in mice for hydroxymethyl 7-indolyl-2-aza-bicyclo[2.2.2]oct-2-ene (14). The simplification of the ibogaine structure appears as a promising approach toward the design of compounds that could reduce the withdrawal symptoms.

The bifunctional μ opioid agonist/antioxidant [Dmt(1)]DALDA is a superior analgesic in an animal model of complex regional pain syndrome-type i.

PubMed

Schiller, Peter W; Nguyen, Thi M-D; Saray, Amy; Poon, Annie Wing Hoi; Laferrière, André; Coderre, Terence J

2015-11-18

Reactive oxygen species (ROS) play an important role in the development of complex regional pain syndrome-Type I (CRPS-I), as also demonstrated with the chronic post ischemia pain (CPIP) animal model of CRPS-I. We show that morphine and the antioxidant N-acetylcysteine (NAC) act synergistically to reduce mechanical allodynia in CPIP rats. The tetrapeptide amide [Dmt(1)]DALDA (H-Dmt-d-Arg-Phe-Lys-NH2) is a potent and selective μ opioid receptor (MOR) agonist with favorable pharmacokinetic properties and with antioxidant activity due to its N-terminal Dmt (2',6'-dimethyltyrosine) residue. In the CPIP model, [Dmt(1)]DALDA was 15-fold more potent than morphine in reversing mechanical allodynia and 4.5-fold more potent as analgesic in the heat algesia test. The results indicate that bifunctional compounds with MOR agonist/antioxidant activity have therapeutic potential for the treatment of CRPS-I.

Review of extended-release formulations of Tramadol for the management of chronic non-cancer pain: focus on marketed formulations

PubMed Central

Kizilbash, Arshi; Ngô-Minh, Cường

2014-01-01

Patients with chronic non-malignant pain report impairments of physical, social, and psychological well-being. The goal of pain management should include reducing pain and improving quality of life. Patients with chronic pain require medications that are able to provide adequate pain relief, have minimum dosing intervals to maintain efficacy, and avoid breakthrough pain. Tramadol has proven efficacy and a favourable safety profile. The positive efficacy and safety profile has been demonstrated historically in numerous published clinical studies as well as from post-marketing experience. It is a World Health Organization “Step 2” opioid analgesic that has been shown to be effective, well-tolerated, and valuable, where treatment with strong opioids is not required. A number of extended release formulations of Tramadol are available in Canada and the United States. An optimal extended release Tramadol formulation would be expected to provide consistent pain control with once daily dosing, few sleep interruptions, flexible dosing schedules, and no limitation on taking with meals. Appropriate treatment options should be based on the above proposed attributes. A comparative review of available extended release Tramadol formulations shows that these medications are not equivalent in their pharmacokinetic profile and this may have implications for selecting the optimal therapy for patients with pain syndromes where Tramadol is an appropriate analgesic agent. Differences in pharmacokinetics amongst the formulations may also translate into varied clinical responses in patients. Selection of the appropriate formulation by the health care provider should therefore be based on the patient’s chronic pain condition, needs, and lifestyle. PMID:24711710

Do Diuretics have Antinociceptive Actions: Studies of Spironolactone, Eplerenone, Furosemide and Chlorothiazide, Individually and with Oxycodone and Morphine.

PubMed

Jokinen, Viljami; Lilius, Tuomas; Laitila, Jouko; Niemi, Mikko; Kambur, Oleg; Kalso, Eija; Rauhala, Pekka

2017-01-01

Spironolactone, eplerenone, chlorothiazide and furosemide are diuretics that have been suggested to have antinociceptive properties, for example via mineralocorticoid receptor antagonism. In co-administration, diuretics might enhance the antinociceptive effect of opioids via pharmacodynamic and pharmacokinetic mechanisms. Effects of spironolactone (100 mg/kg, i.p.), eplerenone (100 mg/kg, i.p.), chlorothiazide (50 mg/kg, i.p.) and furosemide (100 mg/kg, i.p.) were studied on acute oxycodone (0.75 mg/kg, s.c.)- and morphine (3 mg/kg, s.c.)-induced antinociception using tail-flick and hot plate tests in male Sprague Dawley rats. The diuretics were administered 30 min. before the opioids, and behavioural tests were performed 30 and 90 min. after the opioids. Concentrations of oxycodone, morphine and their major metabolites in plasma and brain were quantified by mass spectrometry. In the hot plate test at 30 and 90 min., spironolactone significantly enhanced the antinociceptive effect (% of maximum possible effect) of oxycodone from 10% to 78% and from 0% to 50%, respectively, and that of morphine from 12% to 73% and from 4% to 83%, respectively. The brain oxycodone and morphine concentrations were significantly increased at 30 min. (oxycodone, 46%) and at 90 min. (morphine, 190%). We did not detect any independent antinociceptive effects with the diuretics. Eplerenone and chlorothiazide did not enhance the antinociceptive effect of either opioid. The results suggest that spironolactone enhances the antinociceptive effect of both oxycodone and morphine by increasing their concentrations in the central nervous system. © 2016 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Clinical update on the pharmacology, efficacy and safety of transdermal buprenorphine.

PubMed

Kress, Hans G

2009-03-01

Buprenorphine was not used widely in clinical practice over many years, mainly due to analgesic potency and clinical safety concerns based on misinterpreted animal data. Contrary to previous concerns, however, no analgesic ceiling effect and no antagonism of combined pure mu-opioid receptor agonists is seen within the therapeutic dose range. In recent studies, buprenorphine could be effectively and safely combined with full mu-agonists, and switching between buprenorphine and another opioid provided comparable pain relief based on equianalgesic doses. Moreover, buprenorphine exerts an antihyperalgesic effect, which is due -- at least in part -- to antagonistic activity at kappa-opioid receptors. Buprenorphine pharmacokinetics are not altered by advanced age or renal dysfunction. In addition, the risk of respiratory depression is lower than with other opioids including morphine, hydromorphone, methadone and fentanyl. Unlike morphine and fentanyl, there is no immunosuppressive activity with buprenorphine at therapeutic analgesic doses. Transdermal buprenorphine has significantly improved the clinical use of the drug, providing continuous buprenorphine release for up to 96 h. In clinical trials, patients receiving transdermal buprenorphine experienced significantly greater pain relief, better sleep, and a reduced need for rescue therapy, compared to placebo. Large-scale post-marketing studies have confirmed the effectiveness of transdermal buprenorphine in treating moderate-to-severe cancer and non-cancer pain including neuropathic syndromes. Finally, the comparably low incidence of CNS adverse events and constipation, and the possibility of use in severe renal dysfunction without a need for dose adjustment make buprenorphine well suited for chronic pain management in at-risk patients, such as diabetics, elderly or renally impaired individuals including those requiring haemodialysis.

Rapid Identification of Buprenorphine in Patient Saliva

PubMed Central

Farquharson, Stuart; Dana, Kathryn; Shende, Chetan; Gladding, Zachary; Newcomb, Jenelle; Dascher, Jessica; Petrakis, Ismene L; Arias, Albert J

2017-01-01

Buprenorphine is becoming the medication of choice to help patients withdraw from opioid addiction. However, treatment is compromised by the inability of physicians to assess patient usage during scheduled examinations. Here we describe the development of a point-of-care (POC) analyzer that can rapidly measure both illicit and treatment drugs in patient saliva, ideally in the physician’s office, and with a degree of accuracy similar to chromatography. The analyzer employs a relatively simple supported liquid extraction to isolate the drugs from the saliva and surface-enhanced Raman spectroscopy (SERS) to detect the drugs. The SERS-based POC analyzer was used to identify buprenorphine and opioids in saliva samples by matching library spectra to samples collected from 7 veterans. The total analysis time, including sample preparation, was ~25 minutes. Buprenorphine concentration was estimated between 0 and 3 μg/mL. While no other prescription opioids were detected in any samples, heroin was identified in one sample; Δ-9 tetrahydrocannabinol (THC) was detected in 3 samples; and acetaminophen, caffeine, and nicotine were detected in several samples, none of which interfered with the measurements. The analysis was in very good agreement with urinalysis, correctly identifying the presence or absence of buprenorphine and THC in 13 of 14 measurements. PMID:28944090

Antinociceptive action of DBO 17 and DBO 11 in mice: two 3,8 diazabicyclo (3.2.1.) octane derivates with selective mu opioid receptor affinity.

PubMed

Fadda, P; Barlocco, D; Tronci, S; Cignarella, G; Fratta, W

1997-11-01

Two 3,8 diazabicyclo (3.2.1.) octane derivates, namely DBO 17 and DBO 11, were studied for the opioid-like activity. In the rat brain membrane preparation binding studies, DBO 17 and DBO 11 showed a high affinity and selectivity for the mu opioid receptor (Ki's: 5.1 and 25 nM, respectively). DBO 17 and DBO 11 inhibited the nociceptive response in the hot-plate test of mice with ED50 values of 0.16 mg/kg and 0.44 mg/kg, respectively. The antinociceptive action of both DBO 17 and DBO 11 was blocked by naloxone. Tolerance to the antinociceptive action of DBO 17 and DBO 11 was present after 13 and 7 days of repeated treatment, respectively. Both DBO 17 and DBO 11 were ineffective in morphine-tolerant mice and vice versa. Chronic treatments (three times daily for seven consecutive days) of DBO 17 and DBO 11 induced a naloxone-precipitated withdrawal syndrome in DBO 17 treated mice similar to that in morphine treated mice, whereas in DBO 11 treated mice abstinence signs were virtually absent. These results indicate an interesting pharmacological profile that suggests these compounds as possible new candidates for the clinical treatment of pain.

Effects of chronic fentanyl administration on physical performance of aged rats

PubMed Central

Mitzelfelt, Jeremiah D.; DuPree, Jameson P.; Seo, Dong-oh; Carter, Christy S.; Morgan, Drake

2010-01-01

There is growing concern over the increasing use of opioids to treat chronic pain in the elderly primarily because of the potential increased sensitivity to the adverse side effects. Here, we use a preclinical model (male Brown Norway X F344 rats aged 12, 18, 24, and 30 months) to describe the outcome of chronic fentanyl administration (1.0 mg/kg/day) on various physiological and behavioral measures. Continuous fentanyl administration resulted in an initial decrease in food consumption, followed by the development of tolerance to this effect over a 4-week period and a subsequent increase in food consumption during withdrawal. This change in food consumption was associated with decreases in body weight (predominantly due to a loss of fat mass) that was maintained through early withdrawal. After one month of withdrawal, only the 12-month old animals had fully regained body weight. Fentanyl administration resulted in a decrease in grip strength and an increase in locomotor activity that did not differ across age groups. There was no effect of fentanyl administration on rotarod performance. These results demonstrate that while there is a delayed recovery of body mass with age, the observed changes in behavioral responses are uniform across ages. PMID:20951790

Pharmacokinetics and transplacental distribution of fentanyl in epidural anesthesia for normal pregnant women.

PubMed

Moisés, Elaine Christine Dantas; de Barros Duarte, Luciana; de Carvalho Cavalli, Ricardo; Lanchote, Vera Lúcia; Duarte, Geraldo; da Cunha, Sérgio Pereira

2005-08-01

Fentanyl is an opioid drug widely used as a co-adjuvant in abdominal delivery, a fact that justifies its pharmacokinetic study under these conditions. Our objective was to investigate the pharmacokinetics and placental transfer of fentanyl in parturients whose pregnancies were resolved by cesarian section with epidural anesthesia. Ten clinically normal parturients who delivered at term received 5 ml of 2% lidocaine hydrochloride without a vasoconstrictor for skin and subcutaneous blockade, followed by epidural injection of 2 ml fentanyl citrate (0.05 mg/ml), 15 ml 0.5% bupivacaine hydrochloride with 1:200,000 epinephrine, and 10 ml 2% lidocaine hydrochloride without a vasoconstrictor. Maternal blood samples were collected at various times after injection (1--840 min), and the fentanyl plasma concentrations were determined by gas chromatography-mass spectrometry. Pharmacokinetic analysis was performed using the bi- or tri-compartmental model. The fetal/maternal ratio of the plasma fentanyl was determined at birth. The values of the pharmacokinetic parameters were: t(1/2)alpha=13.5 min, t(1/2)beta=192.5 min, t(1/2)gamma=620 min, AUC(0-infinity)=137.404 ng.min per milliliter, C(l)/f=464.984 ml/min, V(d)/f=299.974 l, C(l)/f/kg=6.875 ml/min per kilogram, and V(d)/f/kg=4.441 l/kg. The latency between drug administration and birth was 28.5 min, with a maternal and fetal plasma concentration of 0.310 and 0.245 ng/ml, respectively, at a median fetal/maternal ratio of 0.892. The study demonstrated a rapid passage of fentanyl from the epidural space to maternal blood and a significant transplacental transfer of maternal fentanyl of about 90%, which should serve as an alert to obstetricians.

Acute Morphine, Chronic Morphine, and Morphine Withdrawal Differently Affect Pleiotrophin, Midkine, and Receptor Protein Tyrosine Phosphatase β/ζ Regulation in the Ventral Tegmental Area.

PubMed

García-Pérez, Daniel; Laorden, M Luisa; Milanés, M Victoria

2017-01-01

Pleiotrophin (PTN) and midkine (MK) are secreted growth factors and cytokines, proposed to be significant neuromodulators with multiple neuronal functions. PTN and MK are generally related with cell proliferation, growth, and differentiation by acting through different receptors. PTN or MK, signaling through receptor protein tyrosine phosphatase β/ζ (RPTPβ/ζ), lead to the activation of extracellular signal-regulated kinases (ERKs) and thymoma viral proto-oncogene (Akt), which induce morphological changes and modulate addictive behaviors. Besides, there is increasing evidence that during the development of drug addiction, astrocytes contribute to the synaptic plasticity by synthesizing and releasing substances such as cytokines. In the present work, we studied the effect of acute morphine, chronic morphine, and morphine withdrawal on PTN, MK, and RPTPβ/ζ expression and on their signaling pathways in the ventral tegmental area (VTA). Present results indicated that PTN, MK, and RPTPβ/ζ levels increased after acute morphine injection, returned to basal levels during chronic opioid treatment, and were upregulated again during morphine withdrawal. We also observed an activation of astrocytes after acute morphine injection and during opiate dependence and withdrawal. In addition, immunofluorescence analysis revealed that PTN, but not MK, was overexpressed in astrocytes and that dopaminergic neurons expressed RPTPβ/ζ. Interestingly, p-ERK 1/2 levels during chronic morphine and morphine withdrawal correlated RPTPβ/ζ expression. All these observations suggest that the neuroprotective and behavioral adaptations that occur during opiate addiction could be, at least partly, mediated by these cytokines.

Estimation of tulathromycin depletion in plasma and milk after subcutaneous injection in lactating goats using a nonlinear mixed-effects pharmacokinetic modeling approach.

PubMed

Lin, Zhoumeng; Cuneo, Matthew; Rowe, Joan D; Li, Mengjie; Tell, Lisa A; Allison, Shayna; Carlson, Jan; Riviere, Jim E; Gehring, Ronette

2016-11-18

Extra-label use of tulathromycin in lactating goats is common and may cause violative residues in milk. The objective of this study was to develop a nonlinear mixed-effects pharmacokinetic (NLME-PK) model to estimate tulathromycin depletion in plasma and milk of lactating goats. Eight lactating goats received two subcutaneous injections of 2.5 mg/kg tulathromycin 7 days apart; blood and milk samples were analyzed for concentrations of tulathromycin and the common fragment of tulathromycin (i.e., the marker residue CP-60,300), respectively, using liquid chromatography mass spectrometry. Based on these new data and related literature data, a NLME-PK compartmental model with first-order absorption and elimination was used to model plasma concentrations and cumulative excreted amount in milk. Monte Carlo simulations with 100 replicates were performed to predict the time when the upper limit of the 95% confidence interval of milk concentrations was below the tolerance. All animals were healthy throughout the study with normal appetite and milk production levels, and with mild-moderate injection-site reactions that diminished by the end of the study. The measured data showed that milk concentrations of the marker residue of tulathromycin were below the limit of detection (LOD = 1.8 ng/ml) 39 days after the second injection. A 2-compartment model with milk as an excretory compartment best described tulathromycin plasma and CP-60,300 milk pharmacokinetic data. The model-predicted data correlated with the measured data very well. The NLME-PK model estimated that tulathromycin plasma concentrations were below LOD (1.2 ng/ml) 43 days after a single injection, and 62 days after the second injection with a 95% confidence. These estimated times are much longer than the current meat withdrawal time recommendation of 18 days for tulathromycin in non-lactating cattle. The results suggest that twice subcutaneous injections of 2.5 mg/kg tulathromycin are a clinically safe extra-label alternative approach for treating pulmonary infections in lactating goats, but a prolonged withdrawal time of at least 39 days after the second injection should be considered to prevent violative residues in milk and any dairy goat being used for meat should have an extended meat withdrawal time.

Treatment for amphetamine withdrawal.

PubMed

Srisurapanont, M; Jarusuraisin, N; Kittirattanapaiboon, P

2001-01-01

Amphetamine withdrawal has been less studied although it is a common problem with a prevalent rate of 87% among amphetamine users. Its symptoms, in particular intense craving, may be a critical factor leading to relapse of amphetamine use. In clinical practice, treatment for cocaine withdrawal has been recommended for the management of amphetamine withdrawal although the pharmacodynamic and pharmacokinetic properties of these two substances are not the same. To search and determine risks, benefits, and costs of a variety of treatments for the management of amphetamine withdrawal. Electronic searches of MEDLINE (1966 - December 2000), EMBASE (1980 - February 2001), CINAHL (1982 - January 2001) and Cochrane Controlled Trials Register (Cochrane Library 2000 issue 4) were undertaken. References to the articles obtained by any means were searched. All relevant randomised controlled trials (RCTs) and controlled clinical trials (CCTs) were included. Participants were people with amphetamine withdrawal, diagnosed by any set of criteria. Any kinds of biological and psychological treatments both alone and combined were examined. A variety of outcomes, for example, number of treatment responders, score changes, were considered. Two reviewers evaluated and extracted the data independently. The dichotomous data were extracted on an intention-to-treat basis in which the dropouts were assigned as participants with the worst outcomes. The Relative Risk (RR) with the 95% confidence interval (95% CI) was used to assess the dichotomous data. The Weighted Mean Difference (WMD) with 95% CI was used to assessed the continuous data. The results of two studies have shown some benefits of amineptine in the treatment of amphetamine withdrawal. Those benefits can be seen in the respects of discontinuation rate and global state, as measured by Clinical Global Impression Scale. However, no direct benefit of amineptine on amphetamine withdrawal symptoms or craving was shown. The evidence about the treatment for amphetamine withdrawal is very limited. Amineptine has limited benefits on some amphetamine withdrawal symptoms. Due to a number of reports of amineptine abuse, it has been withdrawn from the market for a few years. At present, no available treatment has been demonstrated to be effective in the treatment of amphetamine withdrawal. The medications that should be considered for further treatment studies may be those with the propensities to increase dopamine, norepinephrine and/or serotonin activities of the brain. Naturalistic studies of amphetamine withdrawal symptoms and course are also crucial for the development of study designs appropriate for further treatment studies of amphetamine withdrawal.

Opioid receptor probes derived from cycloaddition of the hallucinogen natural product salvinorin A.

PubMed

Lozama, Anthony; Cunningham, Christopher W; Caspers, Michael J; Douglas, Justin T; Dersch, Christina M; Rothman, Richard B; Prisinzano, Thomas E

2011-04-25

As part of our continuing efforts toward more fully understanding the structure-activity relationships of the neoclerodane diterpene salvinorin A, we report the synthesis and biological characterization of unique cycloadducts through [4+2] Diels-Alder cycloaddition. Microwave-assisted methods were developed and successfully employed, aiding in functionalizing the chemically sensitive salvinorin A scaffold. This demonstrates the first reported results for both cycloaddition of the furan ring and functionalization via microwave-assisted methodology of the salvinorin A skeleton. The cycloadducts yielded herein introduce electron-withdrawing substituents and bulky aromatic groups into the C-12 position. Kappa opioid (KOP) receptor space was explored through aromatization of the bent oxanorbornadiene system possessed by the cycloadducts to a planar phenyl ring system. Although dimethyl- and diethylcarboxylate analogues 5 and 6 retain some affinity and selectivity for KOP receptors and are full agonists, their aromatized counterparts 13 and 14 have reduced affinity for KOP receptors. The methods developed herein signify a novel approach toward rapidly probing the structure-activity relationships of furan-containing natural products.

Pharmacodynamic and pharmacokinetic evaluation of buprenorphine + samidorphan for the treatment of major depressive disorder.

PubMed

Ragguett, Renee-Marie; Rong, Carola; Rosenblat, Joshua D; Ho, Roger C; McIntyre, Roger S

2018-04-01

Treatment resistant depression (TRD) represents approximately 20% of all individuals receiving care for major depressive disorder. The opioidergic system is identified as a novel target which hitherto has not been sufficiently investigated in adults with TRD. The combination product buprenorphine + samidorphan is an opioid modulatory agent which has demonstrated replicated evidence of efficacy in TRD without abuse liability. Areas covered: Databases Pubmed, Google Scholar and clinicaltrials.gov were searched from inception through December 2017 for clinical trial information, pharmacokinetics, and pharmacodynamics of buprenorphine + samidorphan. Herein we provide a summary of the available information. Eight clinical trials were identified for inclusion, of the eight trials, five trials had available results and are included in detail in our review. Expert opinion: Buprenorphine + samidorphan has demonstrated efficacy in TRD. Extant evidence surrounding the safety and tolerability profile of buprenorphine + samidorphan does not identify any significant safety concerns. Additional studies are needed in order to assess the long-term safety and efficacy of this product.

Disposition of the anti-ulcer medications ranitidine, cimetidine, and omeprazole following administration of multiple doses to exercised Thoroughbred horses.

PubMed

Knych, H K; Stanley, S D; Arthur, R M; McKemie, D S

2017-01-01

The use of anti-ulcer medications, such as cimetidine, ranitidine, and omeprazole, is common in performance horses. The use of these drugs is regulated in performance horses, and as such a withdrawal time is necessary prior to competition to avoid a medication violation. To the authors' knowledge, there are no reports in the literature describing repeated oral administrations of these drugs in the horse to determine a regulatory threshold and related withdrawal time recommendations. Therefore, the objective of the current study was to describe the disposition and elimination pharmacokinetics of these anti-ulcer medications following oral administration to provide data upon which appropriate regulatory recommendations can be established. Nine exercised Thoroughbred horses were administered 20 mg/kg BID of cimetidine or 8 mg/kg BID of ranitidine, both for seven doses or 2.28 g of omeprazole SID for four doses. Blood samples were collected, serum drug concentrations were determined, and elimination pharmacokinetic parameters were calculated. The serum elimination half-life was 7.05 ± 1.02, 7.43 ± 0.851 and 3.94 ± 1.04 h for cimetidine, ranitidine, and omeprazole, respectively. Serum cimetidine and ranitidine concentrations were above the LOQ and omeprazole and omeprazole sulfide below the LOQ in all horses studied upon termination of sample collection. © 2016 John Wiley & Sons Ltd.

Protocol for diversion of confirmed positive bulk raw milk tankers to calf ranches - A review of the Pharmacokinetics of tetracyclines and sulfonamides in veal calves.

PubMed

DeDonder, K D; Gehring, R; Tell, L A; Riviere, J E

2016-12-01

The tetracyclines (TTC) and sulfonamides are among the most common residues found in bulk raw milk samples. Detection of drug residues in bulk milk (BM) tankers demonstrates that the product is not suitable for human consumption. Discarding BM with residue-contaminated milk is a waste of a valuable commodity, and a repurposing for consumption at calf ranches is a way to recapture some value. However, if calves consuming milk with drug residues are slaughtered for veal, their meat could contain drug residues. The objective of this review is to provide a residue avoidance strategy for TTC and sulfonamide residues in veal. To determine the pharmacokinetic properties of each drug a structured review of the literature was performed and the study inclusion criteria were that the publication used dairy breed calves, with body weight <330 kg or <6 months of age. The most pertinent parameters were determined to be plasma, tissue elimination half-lives, and systemic bioavailability. The results of this review were integrated with milk and tissue testing levels of quantification and tissue tolerances to formulate a recommended withdrawal interval for calves ingesting this milk. The suggested withdrawal interval of 20 days will ensure that no veal calves will test positive for residues from being fed this milk.

Involvement of neuropeptide FF receptors in neuroadaptive responses to acute and chronic opiate treatments

PubMed Central

Elhabazi, K; Trigo, JM; Mollereau, C; Moulédous, L; Zajac, J-M; Bihel, F; Schmitt, M; Bourguignon, JJ; Meziane, H; Petit-demoulière, B; Bockel, F; Maldonado, R; Simonin, F

2012-01-01

BACKGROUND AND PURPOSE Opiates remain the most effective compounds for alleviating severe pain across a wide range of conditions. However, their use is associated with significant side effects. Neuropeptide FF (NPFF) receptors have been implicated in several opiate-induced neuroadaptive changes including the development of tolerance. In this study, we investigated the consequences of NPFF receptor blockade on acute and chronic stimulation of opioid receptors in mice by using RF9, a potent and selective antagonist of NPFF receptors that can be administered systemically. EXPERIMENTAL APPROACH The effects of RF9 were investigated on opioid pharmacological responses including locomotor activity, antinociception, opioid-induced hyperalgesia, rewarding properties and physical dependence. KEY RESULTS RF9 had no effect on morphine-induced horizontal hyperlocomotion and slightly attenuated the decrease induced in vertical activity. Furthermore, RF9 dose-dependently blocked the long-lasting hyperalgesia produced by either acute fentanyl or chronic morphine administration. RF9 also potentiated opiate early analgesic effects and prevented the development of morphine tolerance. Finally, RF9 increased morphine-induced conditioned place preference without producing any rewarding effect by itself and decreased naltrexone-precipitated withdrawal syndrome following chronic morphine treatment. CONCLUSION AND IMPLICATIONS The NPFF system is involved in the development of two major undesirable effects: tolerance and dependence, which are clinically associated with prolonged exposure to opiates. Our findings suggest that NPFF receptors are interesting therapeutic targets to improve the analgesic efficacy of opiates by limiting the development of tolerance, and for the treatment of opioid dependence. PMID:21718302

An Experimental Itch Model in Monkeys

PubMed Central

Ko, M. C. Holden; Naughton, Norah N.

2007-01-01

Background The most common side effect of spinal opioid administration is pruritus, which has been treated with a variety of agents with variable success. Currently, there are few animal models developed to study this side effect. The aim of this study was to establish a nonhuman primate model to pharmacologically characterize the effects of intrathecal administration of morphine. Methods Eight adult rhesus monkeys were used. Scratching responses were videotaped and counted by observers who were blinded to experimental conditions. Antinociception was measured by a warm-water (50°C) tail-withdrawal assay. The dose-response of intrathecal morphine (1-320 μg) for both scratching and antinociception in all subjects was established. An opioid antagonist, nalmefene, was administered either intravenously or subcutaneously to assess its efficacy against intrathecal morphine. Results Intrathecal morphine (1-32 μg) increased scratching in a dose-dependent manner. Higher doses of intrathecal morphine (10-100 μg) produced thermal antinociception in a dose-dependent manner. On the other hand, nalmefene (10-32 μg/kg intravenously) attenuated maximum scratching responses among subjects. Pretreatment with nalmefene (32μg/kg subcutaneously) produced approximately 10-fold rightward shifts of intrathecal morphine dose-response curves for both behavioral effects. Conclusions These data indicate that intrathecal morphine-induced scratching and antinociception are mediated by opioid receptors. The magnitude of nalmefene antagonism of intrathecal morphine is consistent with μ opioid receptor mediation. This experimental itch model is useful for evaluating different agents that may suppress scratching without interfering with antinociception. It may also facilitate the clarification of mechanisms underlying these phenomena. PMID:10719958

Involvement of neuropeptide FF receptors in neuroadaptive responses to acute and chronic opiate treatments.

PubMed

Elhabazi, K; Trigo, J M; Mollereau, C; Moulédous, L; Zajac, J-M; Bihel, F; Schmitt, M; Bourguignon, J J; Meziane, H; Petit-demoulière, B; Bockel, F; Maldonado, R; Simonin, F

2012-01-01

BACKGROUND AND PURPOSE Opiates remain the most effective compounds for alleviating severe pain across a wide range of conditions. However, their use is associated with significant side effects. Neuropeptide FF (NPFF) receptors have been implicated in several opiate-induced neuroadaptive changes including the development of tolerance. In this study, we investigated the consequences of NPFF receptor blockade on acute and chronic stimulation of opioid receptors in mice by using RF9, a potent and selective antagonist of NPFF receptors that can be administered systemically. EXPERIMENTAL APPROACH The effects of RF9 were investigated on opioid pharmacological responses including locomotor activity, antinociception, opioid-induced hyperalgesia, rewarding properties and physical dependence. KEY RESULTS RF9 had no effect on morphine-induced horizontal hyperlocomotion and slightly attenuated the decrease induced in vertical activity. Furthermore, RF9 dose-dependently blocked the long-lasting hyperalgesia produced by either acute fentanyl or chronic morphine administration. RF9 also potentiated opiate early analgesic effects and prevented the development of morphine tolerance. Finally, RF9 increased morphine-induced conditioned place preference without producing any rewarding effect by itself and decreased naltrexone-precipitated withdrawal syndrome following chronic morphine treatment. CONCLUSION AND IMPLICATIONS The NPFF system is involved in the development of two major undesirable effects: tolerance and dependence, which are clinically associated with prolonged exposure to opiates. Our findings suggest that NPFF receptors are interesting therapeutic targets to improve the analgesic efficacy of opiates by limiting the development of tolerance, and for the treatment of opioid dependence. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

Pharmacokinetics of a Novel, Transdermal Fentanyl Solution in Rhesus Macaques (Macaca mulatta)

PubMed Central

Salyards, Gregory W; Lemoy, Marie-Josee; Knych, Heather K; Hill, Ashley E; Christe, Kari L

2017-01-01

Rhesus macaques (Macaca mulatta) are the most commonly used NHP biomedical model and experience both research and clinical procedures requiring analgesia. Opioids are a mainstay of analgesic therapy. A novel, transdermal fentanyl solution (TFS) has been developed as a long-acting, single-administration topical opioid and was reported to provide at least 4 d of effective plasma concentrations in beagles (Canis familiaris). To evaluate the pharmacokinetic profile of TFS in healthy adult rhesus macaques, we used a 2-period, 2-treatment crossover study of a single topical administration of 1.3 (25) and 2.6 mg/kg (50 μL/kg) TFS. TFS was applied to the clipped dorsal skin of adult rhesus macaques (n = 6; 3 male, 3 female) under ketamine sedation (10 mg/kg IM). We hypothesized that TFS in rhesus macaques would provide at least 4 d of effective plasma concentrations (assumed to be ≥ 0.2 ng/mL, based on human studies). Plasma fentanyl concentrations were determined by liquid chromatography–tandem mass spectrometry before drug administration and at 0, 0.5, 1, 2, 4, 8, 12, 24, 36, 48, 60, 72, 96, 120, 144, 168, 240, 336, 408, and 504 h afterward. Noncompartmental pharmacokinetic analysis was performed. For each dose (1.3 and 2.6 mg/kg), respectively, the maximal plasma concentration was 1.95 ± 0.40 and 4.19 ± 0.69 ng/mL, occurring at 21.3 ± 4.1 and 30.7 ± 8.7 h; the AUC was 227.3 ± 31.7 and 447.0 ± 49.1 h/ng/mL, and the terminal elimination half-life was 93.7 ± 7.1 and 98.8 ± 5.4 h. No adverse effects were noted after drug administration at either dose. Macaques maintained plasma fentanyl concentrations of 0.2 ng/mL or greater for at least 7 d after 1.3 mg/kg and at least 10 d after 2.6 mg/kg topical administration of TFS. A single TFS dose may provide efficacious analgesia to rhesus macaques and reduce stress, discomfort, and risk to animals and personnel. PMID:28724494

Adverse effects of analgesics commonly used by older adults with osteoarthritis: focus on non-opioid and opioid analgesics.

PubMed

O'Neil, Christine K; Hanlon, Joseph T; Marcum, Zachary A

2012-12-01

Osteoarthritis (OA) is the most common cause of disability in older adults, and although analgesic use can be helpful, it can also result in adverse drug events. To review the recent literature to describe potential adverse drug events associated with analgesics commonly used by older adults with OA. To identify articles for this review, a systematic search of the English-language literature from January 2001 to June 2012 was conducted using PubMed, MEDLINE, EBSCO, and the Cochrane Database of Systematic Reviews for publications related to the medical management of OA. Search terms used were "analgesics," "acetaminophen," "nonsteroidal anti-inflammatory drugs" (NSAIDs), "opioids," "pharmacokinetics," "pharmacodynamics," and "adverse drug events." The search was restricted to those articles that concerned humans aged ≥65 years. A manual search of the reference lists from identified articles and the authors' article files, book chapters, and recent reviews was conducted to identify additional articles. From these, the authors identified those studies that examined analgesic use in older adults. There are limited data to suggest that non-frail elders are more likely than their younger counterparts to develop acetaminophen-induced hepatotoxicity. However, decreased hepatic phase II metabolism in frail elders may result in increased risk of hepatotoxicity. It is now well established that older adults are at higher risk of NSAID-induced gastrointestinal toxicity and renal insufficiency. Insofar as opioids, the data that suggest an increased risk of falls, fractures, or delirium need to be tempered by the potential risk of inadequately treating severe chronic OA-related pain. Acetaminophen is the mainstay frontline analgesic for treating OA-related pain in older adults. NSAIDs should be limited to short-term use only, and for moderate to severe OA-related pain, opioids may be preferable in individuals without substance abuse or dependence issues. Copyright © 2012 Elsevier HS Journals, Inc. All rights reserved.

Prescription Opioid Use, Misuse, and Diversion among Street Drug Users in New York City

PubMed Central

Rees Davis, W.; Johnson, Bruce D.

2008-01-01

Objective The use of heroin, cocaine, and other drugs is well researched in New York City, but prescription opioids (POs) have been overlooked. This study documents patterns of PO use, misuse, and diversion among street drug users, and begins to indicate how drug culture practices interact with the legitimate therapeutic goals of PO prescriptions (e.g. pain management). Methods Staff completed interviews inquiring about the reasons for use of POs and illicit drugs with 586 street drug users. Ethnographers wrote extensive field notes about subjects’ complex patterns of PO use. Results Methadone was used (71.9%) and sold (64.7%) at a higher level than OxyContin, Vicodin, and Percocet, used by between 34% and 38% of the users and sold by between 28% and 41% of the sellers. Recent PO use is associated with the recency of using heroin and cocaine (p<.001). Half of the heroin/cocaine sellers sold POs, and one quarter of the PO sellers only sold POs. Subjects were classified into four groups by whether they diverted POs or used POs to relieve pain or withdrawal rather than for euphoria. This classification was associated with frequency of PO use, whether POs were obtained from doctors/pharmacies or from drug dealers and family members, and those mostly likely to use POs for pain and withdrawal. Conclusions POs are an important component of street drug users’ drug-taking regimes, especially those who are Physically III Chemical Abusers (PICA). Future research is needed to model PO use, misuse, and diversion among this population. PMID:17913395

Prescription opioid use, misuse, and diversion among street drug users in New York City.

PubMed

Davis, W Rees; Johnson, Bruce D

2008-01-01

The use of heroin, cocaine, and other drugs is well researched in New York City, but prescription opioids (POs) have been overlooked. This study documents patterns of PO use, misuse, and diversion among street drug users, and begins to indicate how drug culture practices interact with the legitimate therapeutic goals of PO prescriptions (e.g. pain management). Staff completed interviews inquiring about the reasons for use of POs and illicit drugs with 586 street drug users. Ethnographers wrote extensive field notes about subjects' complex patterns of PO use. Methadone was used (71.9%) and sold (64.7%) at a higher level than OxyContin, Vicodin, and Percocet, used by between 34% and 38% of the users and sold by between 28% and 41% of the sellers. Recent PO use is associated with the recency of using heroin and cocaine (p<.001). Half of the heroin/cocaine sellers sold POs, and one quarter of the PO sellers only sold POs. Subjects were classified into four groups by whether they diverted POs or used POs to relieve pain or withdrawal rather than for euphoria. This classification was associated with frequency of PO use, whether POs were obtained from doctors/pharmacies or from drug dealers and family members, and those mostly likely to use POs for pain and withdrawal. POs are an important component of street drug users' drug-taking regimes, especially those who are Physically Ill Chemical Abusers (PICA). Future research is needed to model PO use, misuse, and diversion among this population.

Intentional Misuse and Abuse of Loperamide: A New Look at a Drug with "Low Abuse Potential".

PubMed

Borron, Stephen W; Watts, Susan H; Tull, Jonathan; Baeza, Salvador; Diebold, Stephanie; Barrow, Alison

2017-07-01

Despite its opioid properties, loperamide has long been thought to have low abuse potential due to its poor absorption from the gastrointestinal tract and limited potential to cross the blood-brain barrier. A recent patient reportedly taking loperamide to avoid heroin withdrawal symptoms, at doses approximately 100 times those recommended, directed our attention to this issue. 1) Investigate number of cases of intentional loperamide abuse and misuse reported to poison centers between 2009 and 2015; 2) Compile reports of clinical effects of loperamide abuse; and 3) Search for evidence of increasing Internet interest in the central opioid effects of loperamide. For the years 2009 thru 2015, we reviewed exposure calls related to misuse/abuse of loperamide in the Texas Poison Center Network's database and the National Poison Data System. We used Google trend analysis to detect evidence of increased Internet interest in the illicit use of loperamide. Between 2009 and 2015, the number of misuse/abuse calls related to loperamide alone nearly doubled, with about one-third of cases occurring in teens and young adults in their 20s. Of particular concern are reports of significant cardiotoxic effects (∼18% of cases), including conduction defects and various dysrhythmias, sometimes leading to death. Google Trends analysis demonstrates an increasing number of searches for "loperamide high" and "loperamide withdrawal" beginning in 2011. Loperamide misuse/abuse seems to be on the rise. Given its propensity to induce conduction disturbances and dysrhythmias at very high doses, emergency physicians should be vigilant for this form of drug abuse. Copyright © 2017 Elsevier Inc. All rights reserved.

Human Food Safety Implications of Variation in Food Animal Drug Metabolism

PubMed Central

Lin, Zhoumeng; Vahl, Christopher I.; Riviere, Jim E.

2016-01-01

Violative drug residues in animal-derived foods are a global food safety concern. The use of a fixed main metabolite to parent drug (M/D) ratio determined in healthy animals to establish drug tolerances and withdrawal times in diseased animals results in frequent residue violations in food-producing animals. We created a general physiologically based pharmacokinetic model for representative drugs (ceftiofur, enrofloxacin, flunixin, and sulfamethazine) in cattle and swine based on extensive published literature. Simulation results showed that the M/D ratio was not a fixed value, but a time-dependent range. Disease changed M/D ratios substantially and extended withdrawal times; these effects exhibited drug- and species-specificity. These results challenge the interpretation of violative residues based on the use of the M/D ratio to establish tolerances for metabolized drugs. PMID:27302389

High-dose benzodiazepine dependence: a qualitative study of patients' perception on cessation and withdrawal.

PubMed

Liebrenz, Michael; Gehring, Marie-Therese; Buadze, Anna; Caflisch, Carlo

2015-05-13

Benzodiazepine withdrawal syndrome has been reported following attempts to withdraw even from low or therapeutic doses and has been compared to barbiturate and alcohol withdrawal. This experience is known to deter patients from future cessation attempts. Research on other psychotropic substances shows that the reasons and motivations for withdrawal attempts - as well as the experiences surrounding those attempts - at least partially predict future efforts at discontinuation as well as relapse. We therefore aimed to qualitatively explore what motivates patients to discontinue this medication as well as to examine their experiences surrounding previous and current withdrawal attempts and treatment interventions in order to positively influence future help-seeking behavior and compliance. To understand these patients better, we conducted a series of 41 unstructured, narrative, in-depth interviews among adult Swiss patients with a long-term dependent use of benzodiazepines in doses equivalent to more than 40 mg diazepam per day and/or otherwise problematic use (mixing benzodiazepines, escalating dosage, recreational use or illegal purchase). Mayring's qualitative content analysis was used to evaluate findings. These high-dose benzodiazepine-dependent patients decision to change consumption patterns were affected by health concerns, the feeling of being addicted and social factors. Discontinuation attempts were frequent and not very successful with fast relapse. Withdrawal was perceived to be a difficult, complicated, and highly unpredictable process. The first attempt at withdrawal occurred at home and typically felt better than at the clinic. Inpatient treatment was believed to be more effective with long term treatment (approaches) than short term. Patients preferred gradual reduction of usage to abrupt cessation (and had experienced both). While no clear preferences for withdrawal were found for benzodiazepines with specific pharmacokinetic properties, participants frequently based their decision to participate in treatment on the availability of their preferred brand name and furthermore discarding equivalent dosage rationales. Our findings provide greater understanding of the factors that motivate high-dose benzodiazepine-dependent individuals to stop taking these medications, and how they experience withdrawal and treatment strategies. They underscore how patients' perceptions of treatment approaches contribute to compliant or non-compliant behavior.

Relationship between cold pressor pain-sensitivity and sleep quality in opioid-dependent males on methadone treatment

PubMed Central

Lee, Chee Siong; Tan, Soo Choon; Mohamad, Nasir; Lee, Yeong Yeh; Ismail, Rusli

2015-01-01

Aim. Poor sleep quality due to pain has been reported among opioid-dependent male patients on methadone maintenance therapy (MMT) but objective pain data are lacking. This study aimed to investigate the rate of pain-sensitivity using cold pressor test (CPT) and the relationship between pain-sensitivity and sleep quality in this population. Methods. A total of 168 male participants were included into the study. Objective pain-tolerance was evaluated at 0 h and at 24 h after the first CPT. Malay version of the Pittsburgh Sleep Quality Index (PSQI) and the subjective opiate withdrawal scale (SOWS) questionnaires were administered to evaluate the quality of sleep and withdrawal symptoms, respectively. Results. The mean age of study participants was 37.22 (SD 6.20) years old. Mean daily methadone dose was 76.64 (SD 37.63) mg/day, mean global PSQI score was 5.47 (SD 2.74) and mean averaged SOWS score was 5.43 (SD 6.91). The averaged pain-tolerance time ranged from 7 to 300 s with a mean time of 32.16 (SE 2.72) s, slightly below the cut-off score of 37.53 s. More specifically, 78.6% (n = 132) of participants were identified as pain-sensitive (averaged pain-tolerance time ≤37.53 s), and 36 (21.4%) participants were pain-tolerant (averaged pain-tolerance time >37.53 s). The pain-sensitive group reported poorer sleep quality with mean (SD) PSQI of 5.78 (2.80) compared with the pain-tolerant group with mean (SD) PSQI of 4.31 (2.18) (p = 0.005). With analysis of covariance, pain-sensitive group was found to have higher global PSQI scores (adjusted mean 5.76, 95% CI 5.29; 6.22) than pain-tolerant participants (adjusted mean 4.42, 95% CI 3.52; 5.32) (p = 0.010). Conclusions. Majority of opioid-dependent male patients on methadone treatment are pain-sensitive with CPT. Poor sleep quality is associated with cold pressor pain-sensitivity. Pain and sleep complaints in this male population should not be overlooked. PMID:25870765

Role of the Dynorphin/Kappa Opioid Receptor System in the Motivational Effects of Ethanol.

PubMed

Anderson, Rachel I; Becker, Howard C

2017-08-01

Evidence has demonstrated that dynorphin (DYN) and the kappa opioid receptor (KOR) system contribute to various psychiatric disorders, including anxiety, depression, and addiction. More recently, this endogenous opioid system has received increased attention as a potential therapeutic target for treating alcohol use disorders. In this review, we provide an overview and synthesis of preclinical studies examining the influence of alcohol (ethanol [EtOH]) exposure on DYN/KOR expression and function, as well as studies examining the effects of DYN/KOR manipulation on EtOH's rewarding and aversive properties. We then describe work that has characterized effects of KOR activation and blockade on EtOH self-administration and EtOH dependence/withdrawal-related behaviors. Finally, we address how the DYN/KOR system may contribute to stress-EtOH interactions. Despite an apparent role for the DYN/KOR system in motivational effects of EtOH, support comes from relatively few studies. Nevertheless, review of this literature reveals several common themes: (i) rodent strains genetically predisposed to consume more EtOH generally appear to have reduced DYN/KOR tone in brain reward circuitry; (ii) acute and chronic EtOH exposure typically up-regulate the DYN/KOR system; (iii) KOR antagonists reduce behavioral indices of negative affect associated with stress and chronic EtOH exposure/withdrawal; and (iv) KOR antagonists are effective in reducing EtOH consumption, but are often more efficacious under conditions that engender high levels of consumption, such as dependence or stress exposure. These results support the contention that the DYN/KOR system plays a significant role in contributing to dependence- and stress-induced elevation in EtOH consumption. Overall, more comprehensive analyses (on both behavioral and mechanistic levels) are needed to provide additional insight into how the DYN/KOR system is engaged and adapts to influence the motivation effects of EtOH. This information will be critical for the development of new pharmacological agents targeting KORs as promising novel therapeutics for alcohol use disorders and comorbid affective disorders. Copyright © 2017 by the Research Society on Alcoholism.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sawada, Y.; Kawai, R.; McManaway, M.

(3H)Cyclofoxy (CF: 17-cyclopropylmethyl-3,14-dihydroxy-4,5-alpha-epoxy-6-beta-fluoromorp hinan) is an opioid antagonist with affinity to both mu and kappa subtypes that was synthesized for quantitative evaluation of opioid receptor binding in vivo. Two sets of experiments in rats were analyzed. The first involved determining the metabolite-corrected blood concentration and tissue distribution of CF in brain 1 to 60 min after i.v. bolus injection. The second involved measuring brain washout for 15 to 120 s following intracarotid artery injection of CF. A physiologically based model and a classical compartmental pharmacokinetic model were compared. The models included different assumptions for transport across the blood-brain barrier (BBB);more » estimates of nonspecific tissue binding and specific binding to a single opiate receptor site were found to be essentially the same with both models. The nonspecific binding equilibrium constant varied modestly in different brain structures (Keq = 3-9), whereas the binding potential (BP) varied over a much broader range (BP = 0.6-32). In vivo estimates of the opioid receptor dissociation constant were similar for different brain structures (KD = 2.1-5.2 nM), whereas the apparent receptor density (Bmax) varied between 1 (cerebellum) and 78 (thalamus) pmol/g of brain. The receptor dissociation rate constants in cerebrum (k4 = 0.08-0.16 min-1; koff = 0.16-0.23 min-1) and brain vascular permeability (PS = 1.3-3.4 ml/min/g) are sufficiently high to achieve equilibrium conditions within a reasonable period of time. Graphical analysis of the data is inappropriate due to the high tissue-loss rate constant for CF in brain. From these findings, CF should be a very useful opioid receptor ligand for the estimation of the receptor binding parameters in human subjects using (18F)CF and positron emission tomography.« less

Review article: chronobiology: influence of circadian rhythms on the therapy of severe pain.

PubMed

Junker, Uwe; Wirz, Stefan

2010-06-01

Modern pain therapy widely follows the WHO (World Health Organization) guidelines using a three-step 'ladder' for pain relief. This escalating step scheme includes the administration in the order nonopioids, mild opioids and strong opioids, and adjuvants at any step. Analgesics should be given 'by the clock' rather than 'on demand'. However, the chronobiological parameters circadian pain rhythm, circadian efficacy of analgesics, and individual circadian need for analgesics are to be considered. The results of a multitude of studies in chronobiology are not consistent. Therefore, further studies with standardized protocols are needed that allow to assign more consistent rhythms to diseases, pain causes, and analgesic efficacy of opioids. In many cases, each patient perceives pain and its intensity individually during the time of day. By administration of analgesics over a constant or continuous dosage time fluctuations in pain perception and the outcomes of many studies in chronobiology are ignored that prove the influence of biological rhythms on the pharmacokinetic and pharmacodynamic aspects of analgesics. As different types of pain show different rhythms (highest pain intensities arising at different times of the day) analgesics should be dosed flexibly. It is also very important that drug therapy can be adjusted individually to the pain rhythm of the patient as well as to the type and cause of pain. In severe pain, therapy should be particularly careful. A flexible dosage depending on pain intensity and rapid dose adjustment are essentials of a modern pain therapy. Therefore, opioids that are flexible to use are better suited to treat the individual pain of the patient than rigid modified release oral or transdermal systems.

Pharmacokinetics and Abuse Potential of Benzhydrocodone, a Novel Prodrug of Hydrocodone, After Intranasal Administration in Recreational Drug Users.

PubMed

Mickle, Travis C; Guenther, Sven M; Barrett, Andrew C; Roupe, Kathryn Ann; Zhou, Jing; Dickerson, Daniel; Webster, Lynn R

2017-10-28

Developing an acetaminophen-free, immediate-release hydrocodone product remains an unmet medical need; however, new opioid analgesics should not introduce new abuse risks. Benzhydrocodone is a prodrug of hydrocodone that must be metabolized into hydrocodone by enzymes in the intestinal tract to optimally deliver its pharmacologic effects. This study evaluated the intranasal pharmacokinetics and abuse potential of benzhydrocodone active pharmaceutical ingredient (API) compared with hydrocodone bitartrate (HB) API. Single-center, randomized, double-blind, crossover study. Clinical research site. Healthy adult, nondependent, recreational opioid users. Subjects (N = 51 Completers) were randomized to receive 13.34 mg of intranasal benzhydrocodone API and 15.0 mg of intranasal HB API (molar-equivalent doses of hydrocodone). Blood samples were taken, and Drug Liking scores (assessed on a bipolar visual analog scale) were obtained throughout each dosing interval. Nasal irritation and safety were assessed. Peak hydrocodone plasma concentration (Cmax) was 36.0% lower, and total hydrocodone exposures (AUClast and AUCinf) were 20.3% and 19.5% lower, respectively, for benzhydrocodone API compared with HB API (P < 0.0001). All partial AUC values were lower for benzhydrocodone API, with a ≥ 75% reduction in hydrocodone exposure at all time intervals up to one hour postdose (P < 0.0001). Median Tmax of hydrocodone following benzhydrocodone API was delayed by more than one hour compared with HB. Drug Liking score, as assessed by maximal liking (Emax), was significantly lower for benzhydrocodone API vs HB API (P = 0.004), with 45% of subjects showing a ≥ 30% reduction in Drug Liking Emax. Reductions in hydrocodone exposure and associated decreases in Drug Liking relative to HB suggest that the prodrug benzhydrocodone may deter intranasal abuse. © 2017 American Academy of Pain Medicine.

Alterations of naltrexone-induced conditioned place avoidance by pre-exposure to high fructose corn syrup or heroin in Sprague-Dawley rats.

PubMed

Daniels, Stephen; Marshall, Paul; Leri, Francesco

2016-02-01

It has been suggested that withdrawal from sugar produces a set of symptoms that resemble those observed following withdrawal from opiate drugs. This study explored naltrexone-induced withdrawal in animals pre-exposed to acute, chronic, and intermittent high fructose corn syrup (HFCS) or acute and chronic heroin administration. Experiment 1 examined conditioned place avoidance (CPA) induced by different doses of naltrexone (0.01-1 mg/kg) in naïve male Sprague-Dawley rats. In experiment 2, rats received continuous or intermittent home cage HFCS access (0 or 50 %) prior to conditioning with 1 mg/kg naltrexone. In experiment 3, HFCS ingestion was increased by food restriction and rats were conditioned with 3 mg/kg naltrexone. In experiment 4, the timing and quantity of HFCS ingestion (0, 0.5, 1, 2 g/kg) was controlled by intragastric administration, and rats were conditioned with 1 mg/kg naltrexone. In experiment 5, rats received acute (2 mg/kg) or chronic heroin (3.5 mg/kg/day) prior to conditioning with 1 mg/kg naltrexone. Administration of naltrexone produced moderate conditioned place avoidance in naïve rats. Importantly, acute, continuous, and intermittent HFCS pre-exposure did not significantly amplify this effect, but acute and chronic heroin pre-exposure did. As assessed by CPA, these results in rats fail to support the hypothesis that an opioid antagonist can precipitate similar affective withdrawal states following pre-exposure to sugars and opiates.

Preclinical Evaluation of Riluzole: Assessments of Ethanol Self-Administration and Ethanol Withdrawal Symptoms

PubMed Central

Besheer, Joyce; Lepoutre, Veronique; Hodge, Clyde W.

2010-01-01

Background Many of the neurobehavioral effects of ethanol are mediated by inhibition of excitatory N-methyl-d-aspartate (NMDA) and enhancement of inhibitory γ-amino-butyric-acid (GABA) receptor systems. There is growing interest in drugs that alter these systems as potential medications for problems associated with alcoholism. The drug riluzole, approved for treatment of amyotrophic lateral sclerosis (ALS), inhibits NMDA and enhances GABAA receptor system activity. This study was designed to determine the preclinical efficacy of riluzole to modulate ethanol self-administration and withdrawal. Methods Male C57BL/6J mice were trained to lever press on a concurrent fixed-ratio 1 schedule of ethanol (10% v/v) versus water reinforcement during daily 16-hour sessions. Riluzole (1 to 40 mg/kg, IP) was evaluated on ethanol self-administration after acute and chronic (2 week) treatment. To determine if riluzole influences ethanol withdrawal-associated seizures, mice were fed an ethanol-containing or control liquid diet for 18 days. The effects of a single injection of riluzole (30 mg/kg) were examined on handling-induced convulsions after ethanol withdrawal. Results Acute riluzole (30 and 40 mg/kg) reduced ethanol self-administration during the first 4 hours of the session, which corresponds to the known pharmacokinetics of this drug. Ethanol self-administration was also reduced by riluzole after chronic treatment. Riluzole (30 mg/kg) significantly decreased the severity of ethanol-induced convulsions 2 hours after ethanol withdrawal. Conclusions These results demonstrate that riluzole decreases ethanol self-administration and may reduce ethanol withdrawal severity in mice. Thus, riluzole may have utility in the treatment of problems associated with alcoholism. PMID:19426166

[Psychophysiology of sports addiction (exercises addiction)].

PubMed

Krivoshchekov, S G; Lushnikov, O N

2011-01-01

Addiction is a prevalent and growing concern in all aspects of our modern society. There are considerable concerns for the growing frequency of addictions to drugs, alcohol, gambling, eating, and even sex. Though exercise is generally accepted as a positive behaviour that has many benefits associated with enhanced physical and psychological wellbeing, there is an increasing awareness that exercise addiction is becoming a common phenomenon. Theories regarding how exercise can become addictive, and studies of withdrawal from exercise are reviewed. Several physiological mechanisms, including endogenous opioids, catecholamines, functional asymmetry of brain activity and thermoregulation have been implicated in exercise dependence.

Simultaneous analysis of tramadol, O-desmethyltramadol, and N-desmethyltramadol enantiomers in rat plasma by high-performance liquid chromatography-tandem mass spectrometry: application to pharmacokinetics.

PubMed

Godoy, Ana Leonor Pardo Campos; De Moraes, Natália Valadares; Martinez, Edson Zangiacomi; Carvalho, Teresa Maria De Jesus Ponte; Marques, Maria Paula; Lanchote, Vera Lucia

2011-04-01

Tramadol (T) is available as a racemic mixture of (+)-trans-T and (-)-trans-T. The main metabolic pathways are O-demethylation and N-demethylation, producing trans-O-desmethyltramadol (M1) and trans-N-desmethyltramadol (M2) enantiomers, respectively. The analgesic effect of T is related to the opioid activity of (+)-trans-T and (+)-M1 and to the monoaminergic action of (+/-)-trans-T. This is the first study using tandem mass spectrometry as a detection system for the simultaneous analysis of trans-T, M1, and M2 enantiomers. The analytes were resolved on a Chiralpak® AD column using hexane:ethanol (95.5:4.5, v/v) plus 0.1% diethylamine as the mobile phase. The quantitation limits were 0.5 ng/ml for trans-T and M1 and 0.1 ng/ml for M2. The method developed and validated here was applied to a pharmacokinetic study in rats. Male Wistar rats (n=6 at each time point) received a single oral dose of 20 mg/kg racemic trans-T. Blood samples were collected up to 12 h after drug administration. The kinetic disposition of trans-T and M2 was enantioselective (AUC((+))/((-)) ratio=4.16 and 6.36, respectively). The direction and extent of enantioselectivity in the pharmacokinetics of trans-T and M2 in rats were comparable to data previously reported for healthy volunteers, suggesting that rats are a suitable model for enantioselective studies of trans-T pharmacokinetics. Copyright © 2010 Wiley-Liss, Inc.

Pharmacokinetics of acetaminophen, codeine, and the codeine metabolites morphine and codeine-6-glucuronide in healthy Greyhound dogs

PubMed Central

KuKanich, Butch

2009-01-01

The purpose of this study was to determine the pharmacokinetics of codeine and the active metabolites morphine and codeine-6-glucuronide after IV codeine administration and the pharmacokinetics of acetaminophen (APAP), codeine, morphine, and codeine-6-glucuronide after oral administration of combination product containing acetaminophen and codeine to dogs. Six healthy Greyhound dogs were administered 0.734 mg/kg codeine IV and acetaminophen (10.46 mg/kg mean dose) with codeine (1.43 mg/kg mean dose) orally. Blood samples were obtained at predetermined time points for the determination of codeine, morphine, and codeine-6-glucuronide plasma concentrations by LC/MS and acetaminophen by HPLC with UV detection. Codeine was rapidly eliminated after IV administration (T½ =1.22 hr; clearance=29.94 mL/min/kg; volume of distribution=3.17 L/kg) with negligible amounts of morphine present, but large amounts of codeine-6-glucuronide (CMAX=735.75 ng/mL) were detected. The oral bioavailability of codeine was 4%, morphine concentrations were negligible, but large amounts of codeine-6-glucuronide (CMAX=1952.86 ng/mL) were detected suggesting substantial first pass metabolism. Acetaminophen was rapidly absorbed (CMAX=6.74 μg/mL; TMAX=0.85 hr) and eliminated (T½=0.96 hr). In conclusion, the pharmacokinetics of codeine were similar to other opioids in dogs with a short half-life, rapid clearance, large volume of distribution, and poor oral bioavailability. High concentrations of codeine-6-glucuronide were detected after IV and oral administration. PMID:20444020

Pharmacokinetics of acetaminophen, codeine, and the codeine metabolites morphine and codeine-6-glucuronide in healthy Greyhound dogs.

PubMed

KuKanich, B

2010-02-01

The purpose of this study was to determine the pharmacokinetics of codeine and the active metabolites morphine and codeine-6-glucuronide after i.v. codeine administration and the pharmacokinetics of acetaminophen (APAP), codeine, morphine, and codeine-6-glucuronide after oral administration of combination product containing acetaminophen and codeine to dogs. Six healthy Greyhound dogs were administered 0.734 mg/kg codeine i.v. and acetaminophen (10.46 mg/kg mean dose) with codeine (1.43 mg/kg mean dose) orally. Blood samples were collected at predetermined time points for the determination of codeine, morphine, and codeine-6-glucuronide plasma concentrations by LC/MS and acetaminophen by HPLC with UV detection. Codeine was rapidly eliminated after i.v. administration (T(1/2) = 1.22 h; clearance = 29.94 mL/min/kg; volume of distribution = 3.17 L/kg) with negligible amounts of morphine present, but large amounts of codeine-6-glucuronide (C(max) = 735.75 ng/mL) were detected. The oral bioavailability of codeine was 4%, morphine concentrations were negligible, but large amounts of codeine-6-glucuronide (C(max) = 1952.86 ng/mL) were detected suggesting substantial first pass metabolism. Acetaminophen was rapidly absorbed (C(max) = 6.74 microg/mL; T(max) = 0.85 h) and eliminated (T(1/2) = 0.96 h). In conclusion, the pharmacokinetics of codeine was similar to other opioids in dogs with a short half-life, rapid clearance, large volume of distribution, and poor oral bioavailability. High concentrations of codeine-6-glucuronide were detected after i.v. and oral administration.

Individualized Hydrocodone Therapy Based on Phenotype, Pharmacogenetics, and Pharmacokinetic Dosing.

PubMed

Linares, Oscar A; Fudin, Jeffrey; Daly, Annemarie L; Boston, Raymond C

2015-12-01

(1) To quantify hydrocodone (HC) and hydromorphone (HM) metabolite pharmacokinetics with pharmacogenetics in CYP2D6 ultra-rapid metabolizer (UM), extensive metabolizer (EM), and poor metabolizer (PM) metabolizer phenotypes. (2) To develop an HC phenotype-specific dosing strategy for HC that accounts for HM production using clinical pharmacokinetics integrated with pharmacogenetics for patient safety. In silico clinical trial simulation. Healthy white men and women without comorbidities or history of opioid, or any other drug or nutraceutical use, age 26.3±5.7 years (mean±SD; range, 19 to 36 y) and weight 71.9±16.8 kg (range, 50 to 108 kg). CYP2D6 phenotype-specific HC clinical pharmacokinetic parameter estimates and phenotype-specific percentages of HM formed from HC. PMs had lower indices of HC disposition compared with UMs and EMs. Clearance was reduced by nearly 60% and the t1/2 was increased by about 68% compared with EMs. The canonical order for HC clearance was UM>EM>PM. HC elimination mainly by the liver, represented by ke, was reduced about 70% in PM. However, HC's apparent Vd was not significantly different among UMs, EMs, and PM. The canonical order of predicted plasma HM concentrations was UM>EM>PM. For each of the CYP2D6 phenotypes, the mean predicted HM levels were within HM's therapeutic range, which indicates HC has significant phenotype-dependent pro-drug effects. Our results demonstrate that pharmacogenetics afford clinicians an opportunity to individualize HC dosing, while adding enhanced opportunity to account for its conversion to HM in the body.

L-type calcium channel blockade attenuates morphine withdrawal: in vivo interaction between L-type calcium channels and corticosterone.

PubMed

Esmaeili-Mahani, Saeed; Fathi, Yadollah; Motamedi, Fereshteh; Hosseinpanah, Farhad; Ahmadiani, Abolhassan

2008-02-01

Both opioids and calcium channel blockers could affect hypothalamic-pituitary-adrenal (HPA) axis function. Nifedipine, as a calcium channel blocker, can attenuate the development of morphine dependence; however, the role of the HPA axis in this effect has not been elucidated. We examined the effect of nifedipine on the induction of morphine dependency in intact and adrenalectomized (ADX) male rats, as assessed by the naloxone precipitation test. We also evaluated the effect of this drug on HPA activity induced by naloxone. Our results showed that despite the demonstration of dependence in both groups of rats, nifedipine is more effective in preventing of withdrawal signs in ADX rats than in sham-operated rats. In groups that received morphine and nifedipine concomitantly, naloxone-induced corticosterone secretion was attenuated. Thus, we have shown the involvement of the HPA axis in the effect of nifedipine on the development of morphine dependency and additionally demonstrated an in vivo interaction between the L-type Ca2+ channels and corticosterone.

The relevance of the psychological evaluation in drug dependence.

PubMed

Popescu, G; Negrei, C; Bălălău, D; Ciobanu, A M; Baconi, D

2014-01-01

Psychological interventions are considered a central part of the individual psychotherapy in the rehabilitation counseling of psychiatrically symptomatic drug-dependent patients during methadone maintenance treatment in community programs. The need for psychological counseling should be evaluated for each individual patient. Medication is an important part of the treatment and individual psychotherapy focuses on the reduction or total cessation of drug use. The Recipient is G.M. 31, sentenced to a seven-year term of imprisonment for trafficking and use of and high-risk drugs, diagnosed on admission with opioid and methadone dependence, withdrawal syndrome. Following the observation and psychological evaluation, psychiatric and clinical examination, initiation of methadone substitution treatment was recommended, according to the following regimen: twelve 2.5 mg tablets for the first 2 days, followed by increase with about 5 mg per week until the complete remission of withdrawal symptoms, stabilization of the dose but not exceeding 200 mg methadone hydrochloride per day. Specialist monitoring, specialized counseling and individual and group psychotherapy were provided.

Low Doses of Allyphenyline and Cyclomethyline, Effective against Morphine Dependence, Elicit an Antidepressant-like Effect

PubMed Central

2012-01-01

This study demonstrated that cyclomethyline (2) and the corresponding enantiomers (R)-(−)-2 and (S)-(+)-2, displaying α2C-adrenoreceptor (AR) agonism/α2A-AR antagonism, similarly to allyphenyline (1) and its enantiomers, significantly decreased the naloxone-precipitated withdrawal symptoms in mice at very low doses. It also highlighted that such positive effects on morphine dependence can even be improved by additional serotoninergic 5-HT1A receptor (5-HT1A-R) activation. Indeed, 1 or the single (S)-(+)-1, 2, or both its enantiomers, all behaving as α2C-AR agonists/α2A-AR antagonists/5-HT1A-R agonists, alone and at the same low dose, improved morphine withdrawal syndrome and exerted a potent antidepressant-like effect. Therefore, considering the elevated comorbidity between opiate abuse and depressed mood and the benefit of these multifunctional compounds to both disorders, it is possible that they prove more efficacious and less toxic than a cocktail of drugs in managing opioid addiction. PMID:24900506

Development of an opioid self-administration assay to study drug seeking in zebrafish.

PubMed

Bossé, Gabriel D; Peterson, Randall T

2017-09-29

The zebrafish (Danio rerio) has become an excellent tool to study mental health disorders, due to its physiological and genetic similarity to humans, ease of genetic manipulation, and feasibility of small molecule screening. Zebrafish have been shown to exhibit characteristics of addiction to drugs of abuse in non-contingent assays, including conditioned place preference, but contingent assays have been limited to a single assay for alcohol consumption. Using inexpensive electronic, mechanical, and optical components, we developed an automated opioid self-administration assay for zebrafish, enabling us to measure drug seeking and gain insight into the underlying biological pathways. Zebrafish trained in the assay for five days exhibited robust self-administration, which was dependent on the function of the μ-opioid receptor. In addition, a progressive ratio protocol was used to test conditioned animals for motivation. Furthermore, conditioned fish continued to seek the drug despite an adverse consequence and showed signs of stress and anxiety upon withdrawal of the drug. Finally, we validated our assay by confirming that self-administration in zebrafish is dependent on several of the same molecular pathways as in other animal models. Given the ease and throughput of this assay, it will enable identification of important biological pathways regulating drug seeking and could lead to the development of new therapeutic molecules to treat addiction. Copyright © 2017 Elsevier B.V. All rights reserved.

Blockade of phosphodiesterase 4 reverses morphine-induced ventilatory disturbance without loss of analgesia.

PubMed

Kimura, Satoko; Ohi, Yoshiaki; Haji, Akira

2015-04-15

Ventilatory disturbance is a fatal side-effect of opioid analgesics. Separation of analgesia from ventilatory depression is important for therapeutic use of opioids. It has been suggested that opioid-induced ventilatory depression results from a decrease in adenosine 3',5'-cyclic monophosphate content in the respiratory-related neurons. Therefore, we examined the effects of caffeine, a methylxanthine non-selective phosphodiesterase (PDE) inhibitor with adenosine antagonistic activity, and rolipram, a racetam selective PDE4 inhibitor, on ventilatory depression induced by morphine. Spontaneous ventilation and paw withdrawal responses to nociceptive thermal stimulation were measured in anesthetized rats simultaneously. The efferent discharge of the phrenic nerve was recorded in anesthetized, vagotomized, paralyzed and artificially ventilated rats. Rolipram (0.1 and 0.3 mg/kg, i.v.) and caffeine (3.0 and 10.0 mg/kg, i.v.) relieved morphine (1.0 mg/kg, i.v.)-induced ventilatory depression but had no discernible effect on its analgesic action. Rolipram (0.3 and 1.0 mg/kg, i.v.) and caffeine (10.0 and 20.0 mg/kg, i.v.) recovered morphine (3.0 mg/kg, i.v.)-induced prolongation and flattening of inspiratory discharge in the phrenic nerve. Inhibition of PDE4 may be a possible approach for overcoming morphine-induced ventilatory depression without loss of analgesia. Copyright © 2015 Elsevier Inc. All rights reserved.

Bioavailability of curcumin and curcumin glucuronide in the central nervous system of mice after oral delivery of nano-curcumin.

PubMed

Szymusiak, Magdalena; Hu, Xiaoyu; Leon Plata, Paola A; Ciupinski, Paulina; Wang, Zaijie Jim; Liu, Ying

2016-09-10

Curcumin is a bioactive molecule extracted from Turmeric roots that has been recognized to possess a wide variety of important biological activities. Despite its great pharmacological activities, curcumin is highly hydrophobic, which results in poor bioavailability. We have formulated this hydrophobic compound into stable polymeric nanoparticles (nano-curcumin) to enhance its oral absorption. Pharmacokinetic analysis after oral delivery of nano-curcumin in mice demonstrated approximately 20-fold reduction in dose requirement when compared to unformulated curcumin to achieve comparable plasma and central nervous system (CNS) tissue concentrations. This investigation corroborated our previous study of curcumin functionality of attenuating opioid tolerance and dependence, which shows equivalent efficacy of low-dose (20mg/kg) nano-curcumin and high-dose (400mg/kg) pure curcumin in mice. Furthermore, the highly selective and validated liquid chromatography-mass spectrometry (LC-MS) method was developed to quantify curcumin glucuronide, the major metabolite of curcumin. The results suggest that the presence of curcumin in the CNS is essential for prevention and reversal of opioid tolerance and dependence. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterization of the Antinociceptive Effects of the Individual Isomers of Methadone Following Acute and Chronic Administration

PubMed Central

Morgan, Richard W.; Nicholson, Katherine L.

2011-01-01

Methadone is a long-acting opioid used in the treatment of various pain states and substitution therapy in heroin addiction. Extensive behavioral characterization has been carried out utilizing the racemate, but limited investigation has been performed with the individual isomers. While the l-isomer is a potent opioid agonist, the d-isomer has weak μ opioid activity and has also been shown to possess N-methyl-d-aspartate (NMDA) antagonist properties in vitro. The acute antinociceptive effects of the isomers were evaluated in rats using a warm water tail withdrawal procedure at two stimulus intensities (50° and 55° C). Increasing dose ratios of d- to l-methadone were administered chronically to determine the ability of the d-isomer to modulate antinociceptive tolerance to the l-isomer. Acutely, both l- (0.1-5.6 mg/kg, sc) and d- (3.0-56.0 mg/kg, sc) methadone produced antinociception though the efficacy of the d-isomer was limited at 55° C. These effects were dose-dependently blocked by naltrexone (0.01-1.0 mg/kg, sc). Administered chronically, d-methadone (1.7-10 mg/kg, sc) dose-dependently blocked tolerance development to the l-isomer (1.7 mg/kg, sc). These findings support the antinociceptive effects of the isomers being opioid receptor mediated with the l-isomer functioning as a full efficacy agonist whereas the d-isomer appears to have lower efficacy. The ability of nonracemic doses of the d-isomer to prevent tolerance development to the l-isomer may be attributed to partial μ agonist activity however NMDA antagonist activity cannot be discounted. PMID:21836464

Nicotine-specific and non-specific effects of cigarette smoking on endogenous opioid mechanisms.

PubMed

Nuechterlein, Emily B; Ni, Lisong; Domino, Edward F; Zubieta, Jon-Kar

2016-08-01

This study investigates differences in μ-opioid receptor mediated neurotransmission in healthy controls and overnight-abstinent smokers, and potential effects of the OPRM1 A118G genotype. It also examines the effects of smoking denicotinized (DN) and average nicotine (N) cigarettes on the μ-opioid system. Positron emission tomography with (11)C-carfentanil was used to determine regional brain μ-opioid receptor (MOR) availability (non-displaceable binding potential, BPND) in a sample of 19 male smokers and 22 nonsmoking control subjects. Nonsmokers showed greater MOR BPND than overnight abstinent smokers in the basal ganglia and thalamus. BPND in the basal ganglia was negatively correlated with baseline craving levels and Fagerström scores. Interactions between group and genotype were seen in the nucleus accumbens bilaterally and the amygdala, with G-allele carriers demonstrating lower BPND in these regions, but only among smokers. After smoking the DN cigarette, smokers showed evidence of MOR activation in the thalamus and nucleus accumbens. No additional activation was observed after the N cigarette, with a mean effect of increases in MOR BPND (i.e., deactivation) with respect to the DN cigarette effects in the thalamus and left amygdala. Changes in MOR BPND were related to both Fagerström scores and changes in craving. This study showed that overnight-abstinent smokers have lower concentrations of available MORs than controls, an effect that was related to both craving and the severity of addiction. It also suggests that nicotine non-specific elements of the smoking experience have an important role in regulating MOR-mediated neurotransmission, and in turn modulating withdrawal-induced craving ratings. Copyright © 2016 Elsevier Inc. All rights reserved.

A novel orvinol analog, BU08028, as a safe opioid analgesic without abuse liability in primates.

PubMed

Ding, Huiping; Czoty, Paul W; Kiguchi, Norikazu; Cami-Kobeci, Gerta; Sukhtankar, Devki D; Nader, Michael A; Husbands, Stephen M; Ko, Mei-Chuan

2016-09-13

Despite the critical need, no previous research has substantiated safe opioid analgesics without abuse liability in primates. Recent advances in medicinal chemistry have led to the development of ligands with mixed mu opioid peptide (MOP)/nociceptin-orphanin FQ peptide (NOP) receptor agonist activity to achieve this objective. BU08028 is a novel orvinol analog that displays a similar binding profile to buprenorphine with improved affinity and efficacy at NOP receptors. The aim of this preclinical study was to establish the functional profile of BU08028 in monkeys using clinically used MOP receptor agonists for side-by-side comparisons in various well-honed behavioral and physiological assays. Systemic BU08028 (0.001-0.01 mg/kg) produced potent long-lasting (i.e., >24 h) antinociceptive and antiallodynic effects, which were blocked by MOP or NOP receptor antagonists. More importantly, the reinforcing strength of BU08028 was significantly lower than that of cocaine, remifentanil, or buprenorphine in monkeys responding under a progressive-ratio schedule of drug self-administration. Unlike MOP receptor agonists, BU08028 at antinociceptive doses and ∼10- to 30-fold higher doses did not cause respiratory depression or cardiovascular adverse events as measured by telemetry devices. After repeated administration, the monkeys developed acute physical dependence on morphine, as manifested by precipitated withdrawal signs, such as increased respiratory rate, heart rate, and blood pressure. In contrast, monkeys did not show physical dependence on BU08028. These in vivo findings in primates not only document the efficacy and tolerability profile of bifunctional MOP/NOP receptor agonists, but also provide a means of translating such ligands into therapies as safe and potentially abuse-free opioid analgesics.

Endomorphin-2 analogs with C-terminal esterification produce potent systemic antinociception with reduced tolerance and gastrointestinal side effects.

PubMed

Wang, Chang-Lin; Qiu, Ting-Ting; Yang, Dai-Jun; Yuan, Bi-Yu; Han, Feng-Tong; Li, Li; Gu, Ning

2017-04-01

C-terminal esterification of opioid peptides may change their opioid activities due to the modified physicochemical properties. In the present study, the pharmacological activities of C-terminal esterified endomorphin-2 (EM-2) analogs 1-3 were characterized by in vitro metabolic stability and octanol/buffer distribution assays. Also, the antinociceptive profiles in the radiant heat paw withdrawal test and related side effects of these analogs were determined. Our results showed that all three analogs significantly increased the metabolic stability and lipophilicity. Moreover, analogs 1-3 displayed potent antinociceptive activities after intracerebroventricular (i.c.v.) administration. Analogs 1 and 3 exhibited about 2-fold higher antinociception than EM-2, and differential opioid mechanisms were involved. In addition, EM-2 at 50 μmol/kg failed to produce any significant antinociceptive activity after subcutaneous (s.c.) administration, whereas equimolar dose of analogs 1-3 produced significant analgesic effects. Analog 3 showed the highest antinociceptive activity after systemic administration, which was consistent with its in vitro stability and lipophilicity. We further evaluated the antinociceptive tolerance of analogs 1-3. In acute tolerance test, analogs 1-3 shifted the dose-response curves rightward by only 1.4-3.2 fold as determined by tolerance ratio, whereas EM-2 by 5.6-fold, demonstrating reduced antinociceptive tolerance. Also, analogs 1 and 2 decreased chronic antinociceptive tolerance by central and peripheral administration of drugs. In particular, analogs 3 displayed insignificant chronic antinociceptive tolerance. Furthermore, analogs 1-3 were less prone to induce gastrointestinal side effects at analgesic doses. The present investigation gave the evidence that C-terminal esterified modifications of EM-2 will facilitate the development of novel opioid analgesics with reduced side effects. Copyright © 2016 Elsevier Ltd. All rights reserved.

A review of analgesic compounds used in food animals in the United States.

PubMed

Coetzee, Johann F

2013-03-01

Extralabel drug use for pain relief in the United States is regulated under the Animal Medicinal Drug Use Clarification Act. Agents that may provide analgesia in livestock include local anesthetics, nonsteroidal antiinflammatory drugs, opioids, α2-agonists, and N-methyl-d-aspartate receptor antagonists. The challenges associated with providing pain relief in food animals and the salient pharmacokinetic and pharmacodynamic features of the analgesic compounds that could potentially be used in livestock are reviewed. The potential use of novel agents such as bicarbonate, magnesium, ethanol, and gabapentin to augment analgesia is also discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

Beneficial effects of co-treatment with dextromethorphan on prenatally methadone-exposed offspring.

PubMed

Chiang, Yao-Chang; Ye, Li-Ci; Hsu, Kuei-Ying; Liao, Chien-Wei; Hung, Tsai-Wei; Lo, Wan-Jou; Ho, Ing-Kang; Tao, Pao-Luh

2015-03-20

Heroin use among young women of reproductive age has drawn much attention around the world. Although methadone is widely used in maintenance therapy for heroin/morphine addiction, the long-term effects of prenatal exposure to methadone and preventative therapy remain unclear. For revealing this question, female pregnant Sprague-Dawley rats were sub-grouped to receive (1) vehicle, (2) methadone 5 mg/kg at embryonic day 3 (E3) and then 7 mg/kg from E4 to E20, (3) dextromethorphan (DM) 3 mg/kg, and (4) methadone + DM (the rats received methadone followed by DM treatment), subcutaneously, twice a day from E3 to E20. The body weight, natural withdrawal, pain sensitivity, ED50, conditioned place preference and water maze were conducted at different postnatal stages (P1 to P79) of offspring. The quantitative real-time RT-PCR and electrophysiology were also used to measure the gene expression of opioid receptors in the spinal cord and changes of LTP/LTD in the hippocampus, separately. Prenatal exposure to methadone or DM did not affect survival rate, body weight, water maze and LTP or LTD of offspring. However, prenatal methadone significantly increased the withdrawal symptoms, pain sensitivity, addiction liability and decreased the mRNA expression of pain related opioid receptors. Co-administration of DM with methadone in the maternal rats effectively prevented these abnormalities of offspring induced by methadone. Our study clearly showed that co-administration of dextromethorphan with methadone in the maternal rats prevented the adverse effects induced by prenatal methadone exposure. It implies that dextromethorphan may have a potential to be used in combination with methadone for maintenance treatment in pregnant heroin-addicted women to prevent the adverse effects induced by methadone on offspring.

Oxycodone physical dependence and its oral self-administration in C57BL/6J mice.

PubMed

Enga, Rachel M; Jackson, Asti; Damaj, M Imad; Beardsley, Patrick M

2016-10-15

Abuse of prescription opioids, such as oxycodone, has markedly increased in recent decades. While oxycodone's antinociceptive effects have been detailed in several preclinical reports, surprisingly few preclinical reports have elaborated its abuse-related effects. This is particularly surprising given that oxycodone has been in clinical use since 1917. In a novel oral operant self-administration procedure, C57BL/6J mice were trained to self-administer water before introducing increasing concentrations of oxycodone (0.056-1.0mg/ml) under post-prandial conditions during daily, 3-h test sessions. As the concentration of oxycodone increased, the numbers of deliveries first increased, then decreased in an inverted U-shape fashion characteristic of the patterns of other drugs self-administered during limited access conditions. After post-prandial conditions were removed, self-administration at the highest concentration was maintained suggesting oral oxycodone served as a positive reinforcer. In other mice, using a novel regimen of physical dependence, mice were administered increasing doses of oxycodone (9.0-33.0mg/kg, s.c.) over 9 days, challenged with naloxone (0.1-10.0mg/kg, s.c.), and then observed for 30min. Naloxone dose-dependently increased the observed number of somatic signs of withdrawal, suggesting physical dependence of oxycodone was induced under this regimen. This is the first report demonstrating induction of oral operant self-administration of oxycodone and dose-dependent precipitations of oxycodone withdrawal in C57BL/6J mice. The use of oral operant self-administration as well as the novel physical dependence regimen provides useful approaches to further examine the abuse- and dependence-related effects of this highly abused prescription opioid. Copyright © 2016 Elsevier B.V. All rights reserved.

Topiramate in the treatment of substance-related disorders: a critical review of the literature.

PubMed

Shinn, Ann K; Greenfield, Shelly F

2010-05-01

To critically review the literature on topiramate in the treatment of substance-related disorders. A PubMed search of human studies published in English through January 2009 was conducted using the following search terms: topiramate and substance abuse, topiramate and substance dependence, topiramate and withdrawal, topiramate and alcohol, topiramate and nicotine, topiramate and cocaine, topiramate and opiates, and topiramate and benzodiazepines. 26 articles were identified and reviewed; these studies examined topiramate in disorders related to alcohol, nicotine, cocaine, methamphetamine, opioids, Ecstasy, and benzodiazepines. Study design, sample size, topiramate dose and duration, and study outcomes were reviewed. There is compelling evidence for the efficacy of topiramate in the treatment of alcohol dependence. Two trials show trends for topiramate's superiority over oral naltrexone in alcohol dependence, while 1 trial suggests topiramate is inferior to disulfiram. Despite suggestive animal models, evidence for topiramate in treating alcohol withdrawal in humans is slim. Studies of topiramate in nicotine dependence show mixed results. Human laboratory studies that used acute topiramate dosing show that topiramate actually enhances the pleasurable effects of both nicotine and methamphetamine. Evidence for topiramate in the treatment of cocaine dependence is promising, but limited by small sample size. The data on opioids, benzodiazepines, and Ecstasy are sparse. Topiramate is efficacious for the treatment of alcohol dependence, but side effects may limit widespread use. While topiramate's unique pharmacodynamic profile offers a promising theoretical rationale for use across multiple substance-related disorders, heterogeneity both across and within these disorders limits topiramate's broad applicability in treating substance-related disorders. Recommendations for future research include exploration of genetic variants for more targeted pharmacotherapies. ©Copyright 2010 Physicians Postgraduate Press, Inc.

The pharmacokinetics of ketoconazole and its effects on the pharmacokinetics of midazolam and fentanyl in dogs.

PubMed

KuKanich, B; Hubin, M

2010-02-01

Ketoconazole inhibits the Cytochrome P450 3A12 (CYP3A12) metabolizing enzyme as well as the p-glycoprotein efflux pump. The extent and clinical consequence of these effects are poorly understood in dogs. The objective was to assess the pharmacokinetics of ketoconazole after single and multiple doses and the effect of multiple doses of ketoconazole on midazolam (a known CYP3A12 substrate) and the opioid fentanyl. Six greyhound dogs were studied. The study consisted of three phases. Phase 1 consisted of i.v. midazolam (0.23 mg/kg base) and fentanyl (15.71 microg/kg base). Phase 2 consisted of a single oral dose of ketoconazole (mean dose 12.34 mg/kg). Phase 3 consisted of i.v. midazolam (0.23 mg/kg) and fentanyl (10 microg/kg) after 5 days of oral ketoconazole (12.25 mg/kg/day). Ketoconazole significantly inhibited its own elimination with the mean residence time (MRT) increasing from 6.24 h in Phase 1 to 12.54 h in Phase 3. Ketoconazole significantly decreased the elimination of midazolam, as expected, with the MRT increasing from 0.81 to 1.49 h. The elimination of fentanyl was not significantly altered by co-administration of ketoconazole with the MRT being 3.90 and 6.35 h. The MRT was the most robust estimate of decreased drug elimination.

The pharmacokinetics of propofol in ICU patients undergoing long-term sedation.

PubMed

Smuszkiewicz, Piotr; Wiczling, Paweł; Przybyłowski, Krzysztof; Borsuk, Agnieszka; Trojanowska, Iwona; Paterska, Marta; Matysiak, Jan; Kokot, Zenon; Grześkowiak, Edmund; Bienert, Agnieszka

2016-11-01

The aim of this study was to characterize the pharmacokinetics (PK) of propofol in ICU patients undergoing long-term sedation and to assess the influence of routinely collected covariates on the PK parameters. Propofol concentration-time profiles were collected from 29 patients. Non-linear mixed-effects modelling in NONMEM 7.2 was used to analyse the observed data. The propofol pharmacokinetics was best described with a three-compartment disposition model. Non-parametric bootstrap and a visual predictive check were used to evaluate the adequacy of the developed model to describe the observations. The typical value of the propofol clearance (1.46 l/min) approximated the hepatic blood flow. The volume of distribution at steady state was high and was equal to 955.1 l, which is consistent with other studies involving propofol in ICU patients. There was no statistically significant covariate relationship between PK parameters and opioid type, SOFA score on the day of admission, APACHE II, predicted death rate, reason for ICU admission (sepsis, trauma or surgery), gender, body weight, age, infusion duration and C-reactive protein concentration. The population PK model was developed successfully to describe the time-course of propofol concentration in ICU patients undergoing prolonged sedation. Despite a very heterogeneous group of patients, consistent PK profiles were observed. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Assessment of gonadotropins and testosterone hormone levels in regular Mitragyna speciosa (Korth.) users.

PubMed

Singh, Darshan; Murugaiyah, Vikneswaran; Hamid, Shahrul Bariyah Sahul; Kasinather, Vicknasingam; Chan, Michelle Su Ann; Ho, Eric Tatt Wei; Grundmann, Oliver; Chear, Nelson Jeng Yeou; Mansor, Sharif Mahsufi

2018-07-15

Mitragyna speciosa (Korth.) also known as kratom, is a native medicinal plant of Southeast Asia with opioid-like effects. Kratom tea/juice have been traditionally used as a folk remedy and for controlling opiate withdrawal in Malaysia. Long-term opioid use is associated with depletion in testosterone levels. Since kratom is reported to deform sperm morphology and reduce sperm motility, we aimed to clinically investigate the testosterone levels following long-term kratom tea/juice use in regular kratom users. A total of 19 regular kratom users were recruited for this cross-sectional study. A full-blood test was conducted including determination of testosterone level, follicle stimulating hormone (FSH) and luteinizing hormone (LH) profile, as well as hematological and biochemical parameters of participants. We found long-term kratom tea/juice consumption with a daily mitragynine dose of 76.23-94.15 mg did not impair testosterone levels, or gonadotrophins, hematological and biochemical parameters in regular kratom users. Regular kratom tea/juice consumption over prolonged periods (>2 years) was not associated with testosterone impairing effects in humans. Copyright © 2018 Elsevier B.V. All rights reserved.

Long-term potentiation in spinal nociceptive pathways as a novel target for pain therapy

PubMed Central

2011-01-01

Long-term potentiation (LTP) in nociceptive spinal pathways shares several features with hyperalgesia and has been proposed to be a cellular mechanism of pain amplification in acute and chronic pain states. Spinal LTP is typically induced by noxious input and has therefore been hypothesized to contribute to acute postoperative pain and to forms of chronic pain that develop from an initial painful event, peripheral inflammation or neuropathy. Under this assumption, preventing LTP induction may help to prevent the development of exaggerated postoperative pain and reversing established LTP may help to treat patients who have an LTP component to their chronic pain. Spinal LTP is also induced by abrupt opioid withdrawal, making it a possible mechanism of some forms of opioid-induced hyperalgesia. Here, we give an overview of targets for preventing LTP induction and modifying established LTP as identified in animal studies. We discuss which of the various symptoms of human experimental and clinical pain may be manifestations of spinal LTP, review the pharmacology of these possible human LTP manifestations and compare it to the pharmacology of spinal LTP in rodents. PMID:21443797

Anti-nociceptive effects of calcitonin gene-related peptide in nucleus raphe magnus of rats: an effect attenuated by naloxone.

PubMed

Huang, Y; Brodda-Jansen, G; Lundeberg, T; Yu, L C

2000-08-04

The present study investigated the role of calcitonin gene-related peptide (CGRP) on nociception in nucleus raphe magnus (NRM) and the interaction between CGRP and opioid peptides in NRM of rats. CGRP-like immunoreactivity was found at a concentration of 6.0+/-0. 77 pmol/g in NRM tissue of ten samples of rats, suggesting that it may contribute to physiological responses orchestrated by the NRM. The hindpaw withdrawal latency (HWL) to thermal and mechanical stimulation increased significantly after intra-NRM administration of 0.5 or 1 nmol of CGRP in rats, but not 0.25 nmol. The anti-nociceptive effect induced by CGRP was antagonized by following intra-NRM injection of 1 nmol of the CGRP receptor antagonist CGRP8-37. Furthermore, the CGRP-induced anti-nociceptive effect was attenuated by following intra-NRM administration of 6 nmol of naloxone. The results indicate that CGRP and its receptors play an important role in anti-nociception, and there is a possible interaction between CGRP and opioid peptides in NRM of rats.

Opioid Receptor Probes Derived from Cycloaddition of the Hallucinogen Natural Product Salvinorin A†

PubMed Central

Lozama, Anthony; Cunningham, Christopher W.; Caspers, Michael J.; Douglas, Justin T.; Dersch, Christina M.; Rothman, Richard B.; Prisinzano, Thomas E.

2011-01-01

As part of our continuing efforts toward more fully understanding the structure-activity relationships of the neoclerodane diterpene salvinorin A, we report the synthesis and biological characterization of unique cycloadducts through [4+2] Diels-Alder cycloaddition. Microwave-assisted methods were developed and successfully employed, aiding in functionalizing the chemically sensitive salvinorin A scaffold. This demonstrates the first reported results for both cycloaddition of the furan ring and functionalization via microwave-assisted methodology of the salvinorin A skeleton. The cycloadducts yielded herein introduce electron-withdrawing substituents and bulky aromatic groups into the C-12 position. Kappa opioid (KOP) receptor space was explored through aromatization of the bent oxanorbornadiene system possessed by the cycloadducts to a planar phenyl ring system. Although dimethyl- and diethylcarboxylate analogues 5 and 6 retain some affinity and selectivity for KOP receptors and are full agonists, their aromatized counterparts 13 and 14 have reduced affinity for KOP receptors. The methods developed herein signify a novel approach toward rapidly probing the structure-activity relationships of furan containing natural products. PMID:21338114

Evidence for the Efficacy of Systemic Opioid-Sparing Analgesics in Pediatric Surgical Populations: A Systematic Review.

PubMed

Zhu, Alyssa; Benzon, Hubert A; Anderson, T Anthony

2017-11-01

While a large number of studies has examined the efficacy of opioid-sparing analgesics in adult surgical populations, fewer studies are available to guide postoperative pain treatment in pediatric patients. We systematically reviewed available publications on the use of systemic nonopioid agents for postoperative analgesia in pediatric surgical populations. A comprehensive literature search identified meta-analyses and randomized controlled trials (RCTs) assessing the effects of systemic, nonopioid agents on postoperative narcotic requirements or pain scores in pediatric surgical populations. If a meta-analysis was located, we summarized its results and any RCTs published after it. We located and reviewed 11 acetaminophen RCTs, 1 nonsteroidal anti-inflammatory drug (NSAID) meta-analysis, 2 NSAID RCTs, 1 dexamethasone meta-analysis, 3 dexamethasone RCTs, 2 ketamine meta-analyses, 5 ketamine RCTs, 2 gabapentin RCTs, 1 clonidine meta-analysis, 3 magnesium RCTs, 2 dexmedetomidine meta-analyses, and 1 dextromethorphan RCT. No meta-analyses or RCTs were found assessing the perioperative efficacy of intravenous lidocaine, amantadine, pregabalin, esmolol, or caffeine in pediatric surgical patients. The available evidence is limited, but suggests that perioperative acetaminophen, NSAIDs, dexamethasone, ketamine, clonidine, and dexmedetomidine may decrease postoperative pain and opioid consumption in some pediatric surgical populations. Not enough, or no, data exist from which to draw conclusions on the perioperative use of gabapentin, magnesium, dextromethorphan, lidocaine, amantadine, pregabalin, esmolol, and caffeine in pediatric surgical patients. Further pharmacokinetic and pharmacodynamics studies to establish both the clinical benefit and efficacy of nonopioid analgesia in pediatric populations are needed.

Pharmacokinetics of doxycycline in laying hens after intravenous and oral administration.

PubMed

Yang, F; Si, H B; Wang, Y Q; Zhao, Z S; Zhou, B H; Hao, X Q

2016-08-01

The pharmacokinetics of doxycycline in laying hens was investigated after a single intravenous (IV) or an oral (PO) dose at 20 mg/kg body weight. The concentrations of doxycycline in plasma samples were determined by high-performance liquid chromatography with an ultraviolet detector, and pharmacokinetic parameters were calculated using a compartmental model method. The disposition of doxycycline after one single IV injection was best described by a two-compartment open model and the main pharmacokinetic parameters were as follows: volume of distribution (Vd) was 865.15 ± 127.64 ml/kg, distribution rate constant (α) was (2.28 ± 0.38) 1/h, elimination rate constant (β) was 0.08 ± 0.02 1/h and total body clearance (Cl) was104.11 ± 18.32 ml/h/kg, while after PO administration, the concentration versus time curve was best described by a one-compartment open model and absorption rate constant (Ka), peak concentration (Cmax), time to reach Cmax (tmax) and absolute bioavailability (F) were 2.55 ± 1.40 1/h, 5.88 ± 0.70 μg/ml, 1.73 ± 0.75 h and 52.33%, respectively. The profile of doxycycline exhibited favourable pharmacokinetic characteristics in laying hens, such as quick absorption and slow distribution and elimination, though oral bioavailability was relatively low. A multiple-dosing regimen (a dose of 20 mg/kg/d for 3 consecutive days) of doxycycline was recommended to treat infections in laying hens. But a further study should be conducted to determine the withdrawal time of doxycycline in eggs.

Monte Carlo Simulations Suggest Current Chlortetracycline Drug-Residue Based Withdrawal Periods Would Not Control Antimicrobial Resistance Dissemination from Feedlot to Slaughterhouse.

PubMed

Cazer, Casey L; Ducrot, Lucas; Volkova, Victoriya V; Gröhn, Yrjö T

2017-01-01

Antimicrobial use in beef cattle can increase antimicrobial resistance prevalence in their enteric bacteria, including potential pathogens such as Escherichia coli . These bacteria can contaminate animal products at slaughterhouses and cause food-borne illness, which can be difficult to treat if it is due to antimicrobial resistant bacteria. One potential intervention to reduce the dissemination of resistant bacteria from feedlot to consumer is to impose a withdrawal period after antimicrobial use, similar to the current withdrawal period designed to prevent drug residues in edible animal meat. We investigated tetracycline resistance in generic E. coli in the bovine large intestine during and after antimicrobial treatment by building a mathematical model of oral chlortetracycline pharmacokinetics-pharmacodynamics and E. coli population dynamics. We tracked three E. coli subpopulations (susceptible, intermediate, and resistant) during and after treatment with each of three United States chlortetracycline indications (liver abscess reduction, disease control, disease treatment). We compared the proportion of resistant E. coli before antimicrobial use to that at several time points after treatment and found a greater proportion of resistant enteric E. coli after the current withdrawal periods than prior to treatment. In order for the proportion of resistant E. coli in the median beef steer to return to the pre-treatment level, withdrawal periods of 15 days after liver abscess reduction dosing (70 mg daily), 31 days after disease control dosing (350 mg daily), and 36 days after disease treatment dosing (22 mg/kg bodyweight for 5 days) are required in this model. These antimicrobial resistance withdrawal periods would be substantially longer than the current U.S. withdrawals of 0-2 days or Canadian withdrawals of 5-10 days. One published field study found similar time periods necessary to reduce the proportion of resistant E. coli following chlortetracycline disease treatment to those suggested by this model, but additional carefully designed field studies are necessary to confirm the model results. This model is limited to biological processes within the cattle and does not include resistance selection in the feedlot environment or co-selection of chlortetracycline resistance following other antimicrobial use.

Monte Carlo Simulations Suggest Current Chlortetracycline Drug-Residue Based Withdrawal Periods Would Not Control Antimicrobial Resistance Dissemination from Feedlot to Slaughterhouse

PubMed Central

Cazer, Casey L.; Ducrot, Lucas; Volkova, Victoriya V.; Gröhn, Yrjö T.

2017-01-01

Antimicrobial use in beef cattle can increase antimicrobial resistance prevalence in their enteric bacteria, including potential pathogens such as Escherichia coli. These bacteria can contaminate animal products at slaughterhouses and cause food-borne illness, which can be difficult to treat if it is due to antimicrobial resistant bacteria. One potential intervention to reduce the dissemination of resistant bacteria from feedlot to consumer is to impose a withdrawal period after antimicrobial use, similar to the current withdrawal period designed to prevent drug residues in edible animal meat. We investigated tetracycline resistance in generic E. coli in the bovine large intestine during and after antimicrobial treatment by building a mathematical model of oral chlortetracycline pharmacokinetics-pharmacodynamics and E. coli population dynamics. We tracked three E. coli subpopulations (susceptible, intermediate, and resistant) during and after treatment with each of three United States chlortetracycline indications (liver abscess reduction, disease control, disease treatment). We compared the proportion of resistant E. coli before antimicrobial use to that at several time points after treatment and found a greater proportion of resistant enteric E. coli after the current withdrawal periods than prior to treatment. In order for the proportion of resistant E. coli in the median beef steer to return to the pre-treatment level, withdrawal periods of 15 days after liver abscess reduction dosing (70 mg daily), 31 days after disease control dosing (350 mg daily), and 36 days after disease treatment dosing (22 mg/kg bodyweight for 5 days) are required in this model. These antimicrobial resistance withdrawal periods would be substantially longer than the current U.S. withdrawals of 0–2 days or Canadian withdrawals of 5–10 days. One published field study found similar time periods necessary to reduce the proportion of resistant E. coli following chlortetracycline disease treatment to those suggested by this model, but additional carefully designed field studies are necessary to confirm the model results. This model is limited to biological processes within the cattle and does not include resistance selection in the feedlot environment or co-selection of chlortetracycline resistance following other antimicrobial use. PMID:29033901

Sex Differences in the Effect of Finasteride on Acute Ethanol Withdrawal Severity in C57BL/6J and DBA/2J Mice

PubMed Central

Gorin-Meyer, Rebecca E.; Wiren, Kristine M.; Tanchuck, Michelle A.; Long, Season L.; Yoneyama, Naomi; Finn, Deborah A.

2007-01-01

The neurosteroid allopregnanolone (ALLO) is a potent positive modulator of γ-aminobutyric acidA (GABAA) receptors that can modulate ethanol (EtOH) withdrawal. The 5α-reductase inhibitor finasteride can block the formation of ALLO and other GABAergic neurosteroids and also reduce certain effects of EtOH. Treatment with finasteride during chronic EtOH exposure decreased EtOH withdrawal severity and blood EtOH concentrations (BECs), suggesting an additional effect of finasteride on EtOH pharmacokinetics. Thus, the purpose of the present study was to determine the effect of finasteride on acute EtOH withdrawal severity, to minimize the effect of finasteride on EtOH metabolism. Male and female C57BL/6J and DBA/2J mice received a pretreatment of finasteride (50 mg/kg i.p.) or vehicle 24 hours prior to an injection of EtOH (4 g/kg i.p.) or saline. Handling-induced convulsions (HICs) were scored at baseline, and then over a 24 hr period after EtOH or saline injection. In another experiment, plasma estradiol and corticosterone levels were assessed at selected time points (0, 2, 8, and 24 hrs). In a final study, retro-orbital blood samples were collected at 30, 60, 120, and 240 minutes post-EtOH administration to access finasteride’s effects on EtOH clearance parameters. Pretreatment with finasteride increased acute EtOH withdrawal severity in female C57BL/6J and DBA/2J mice but decreased withdrawal severity in male mice of both strains. Finasteride did not alter BECs, EtOH clearance, estradiol, or corticosterone concentrations in a manner that appeared to contribute to the sex difference in finasteride’s effect on acute EtOH withdrawal severity. These findings suggest that male and female C57BL/6J and DBA/2J mice differ in their sensitivity to changes in ALLO or other GABAergic neurosteroid levels during acute EtOH withdrawal. Sex differences in the modulation of GABAergic 5α-reduced steroids may be an important consideration in understanding and developing therapeutic interventions in alcoholics. PMID:17428611

Pharmacokinetics and behavioral effects of liposomal hydromorphone suitable for perioperative use in rhesus macaques

PubMed Central

KuKanich, Butch; Schmidt, Brynn; Heath, Timothy D.; Brown, Carolyn

2011-01-01

Introduction This study aims to evaluate the pharmacokinetic, behavioral, and motor effects of a liposomal preparation of hydromorphone hydrochloride (LE-hydro) in rhesus monkeys. We administered either 2 mg/kg of LE-hydro (n=8) subcutaneous (s.c.) or 0.1 mg/kg of standard pharmaceutical hydromorphone HCl (hydro) preparation either intravenous (i.v.; n=4) or s.c. (n=5). Materials and methods Serial blood samples were drawn after injection and analyzed for serum hydro concentration by liquid chromatography/mass spectrometry. Following s.c. injection of 0.1 mg/kg hydro or 2 mg/kg LE-hydro, behavioral evaluations were conducted in groups of rhesus monkeys (n=10/group) in the presence of a compatible stimulus animal and motor skills were also evaluated (n=10/group). The motor skills test consisted of removing a food reward (carrot ring) from either a straight peg (simple task) or a curved peg (difficult task). Results LE-hydro (MRT0-INF = 105.9 h) demonstrated extended-release pharmacokinetics compared to hydro when administered by either i.v. (MRT0-INF =1.1 h) or s.c. (MRT0-INF =1.3 h) routes. Hydro did not affect motor performance of the simpler task, but the monkeys’ performance deteriorated on the more difficult task at 0.5 and 1 h after injection. LE-hydro had no effect on motor skills in either the simpler or more difficult task. Conclusions The results of these studies indicate that LE-hydro has a pharmacokinetic and behavioral side effects profile consistent with an analgesic that could be tested for surgical use in animals. Our studies also expand the use of rhesus monkeys as a translational behavioral pharmacodynamics model for testing extended-release opioid medication. PMID:21404039

Disruption of δ-opioid receptor phosphorylation at threonine 161 attenuates morphine tolerance in rats with CFA-induced inflammatory hypersensitivity.

PubMed

Chen, Hai-Jing; Xie, Wei-Yan; Hu, Fang; Zhang, Ying; Wang, Jun; Wang, Yun

2012-04-01

Our previous study identified Threonine 161 (Thr-161), located in the second intracellular loop of the δ-opioid receptor (DOR), as the only consensus phosphorylation site for cyclin-dependent kinase 5 (Cdk5). The aim of this study was to assess the function of DOR phosphorylation by Cdk5 in complete Freund's adjuvant (CFA)-induced inflammatory pain and morphine tolerance. Dorsal root ganglion (DRG) neurons of rats with CFA-induced inflammatory pain were acutely dissociated and the biotinylation method was used to explore the membrane localization of phosphorylated DOR at Thr-161 (pThr-161-DOR), and paw withdrawal latency was measured after intrathecal delivery of drugs or Tat-peptide, using a radiant heat stimulator in rats with CFA-induced inflammatory pain. Both the total amount and the surface localization of pThr-161-DOR were significantly enhanced in the ipsilateral DRG following CFA injection. Intrathecal delivery of the engineered Tat fusion-interefering peptide corresponding to the second intracellular loop of DOR (Tat-DOR-2L) increased inflammatory hypersensitivity, and inhibited DOR- but not µ-opioid receptor-mediated spinal analgesia in CFA-treated rats. However, intrathecal delivery of Tat-DOR-2L postponed morphine antinociceptive tolerance in rats with CFA-induced inflammatory pain. Phosphorylation of DOR at Thr-161 by Cdk5 attenuates hypersensitivity and potentiates morphine tolerance in rats with CFA-induced inflammatory pain, while disruption of the phosphorylation of DOR at Thr-161 attenuates morphine tolerance.

Sativex oromucosal spray as adjunctive therapy in advanced cancer patients with chronic pain unalleviated by optimized opioid therapy: two double-blind, randomized, placebo-controlled phase 3 studies.

PubMed

Fallon, Marie T; Albert Lux, Eberhard; McQuade, Robert; Rossetti, Sandro; Sanchez, Raymond; Sun, Wei; Wright, Stephen; Lichtman, Aron H; Kornyeyeva, Elena

2017-08-01

Opioids are critical for managing cancer pain, but may provide inadequate relief and/or unacceptable side effects in some cases. To assess the analgesic efficacy of adjunctive Sativex (Δ 9 -tetrahydrocannabinol (27 mg/mL): cannabidiol (25 mg/mL)) in advanced cancer patients with chronic pain unalleviated by optimized opioid therapy. This report describes two phase 3, double-blind, randomized, placebo-controlled trials. Eligible patients had advanced cancer and average pain numerical rating scale (NRS) scores ≥4 and ≤8 at baseline, despite optimized opioid therapy. In Study-1, patients were randomized to Sativex or placebo, and then self-titrated study medications over a 2-week period per effect and tolerability, followed by a 3-week treatment period. In Study-2, all patients self-titrated Sativex over a 2-week period. Patients with a ≥15% improvement from baseline in pain score were then randomized 1:1 to Sativex or placebo, followed by 5-week treatment period (randomized withdrawal design). The primary efficacy endpoint (percent improvement (Study-1) and mean change (Study-2) in average daily pain NRS scores) was not met in either study. Post hoc analyses of the primary endpoints identified statistically favourable treatment effect for Sativex in US patients <65 years (median treatment difference: 8.8; 95% confidence interval (CI): 0.00-17.95; p = 0.040) that was not observed in patients <65 years from the rest of the world (median treatment difference: 0.2; 95% CI: -5.00 to 7.74; p = 0.794). Treatment effect in favour of Sativex was observed on quality-of-life questionnaires, despite the fact that similar effects were not observed on NRS score. The safety profile of Sativex was consistent with earlier studies, and no evidence of abuse or misuse was identified. Sativex did not demonstrate superiority to placebo in reducing self-reported pain NRS scores in advanced cancer patients with chronic pain unalleviated by optimized opioid therapy, although further exploration of differences between United States and patients from the rest of the world is warranted.

Synthesis and Structure-Activity Relationships of (-)-cis-N-Normetazocine-Based LP1 Derivatives.

PubMed

Pasquinucci, Lorella; Parenti, Carmela; Amata, Emanuele; Georgoussi, Zafiroula; Pallaki, Paschalina; Camarda, Valeria; Calò, Girolamo; Arena, Emanuela; Montenegro, Lucia; Turnaturi, Rita

2018-05-05

(−)- cis - N -Normetazocine represents a rigid scaffold able to mimic the tyramine moiety of endogenous opioid peptides, and the introduction of different N -substituents influences affinity and efficacy of respective ligands at MOR (mu opioid receptor), DOR (delta opioid receptor), and KOR (kappa opioid receptor). We have previously identified LP1, a MOR/DOR multitarget opioid ligand, with an N -phenylpropanamido substituent linked to (−)- cis - N -Normetazocine scaffold. Herein, we report the synthesis, competition binding and calcium mobilization assays of new compounds 10 ⁻ 16 that differ from LP1 by the nature of the N -substituent. In radioligand binding experiments, the compounds 10 ⁻ 13 , featured by an electron-withdrawing or electron-donating group in the para position of phenyl ring, displayed improved affinity for KOR (K i = 0.85⁻4.80 μM) in comparison to LP1 (7.5 μM). On the contrary, their MOR and DOR affinities were worse (K i = 0.18⁻0.28 μM and K i = 0.38⁻1.10 μM, respectively) with respect to LP1 values (K i = 0.049 and 0.033 μM). Analogous trends was recorded for the compounds 14 ⁻ 16 , featured by indoline, tetrahydroquinoline, and diphenylamine functionalities in the N -substituent. In calcium mobilization assays, the compound 10 with a p -fluorophenyl in the N -substituent shared the functional profile of LP1 (pEC 50 MOR = 7.01), although it was less active. Moreover, the p -methyl- ( 11 ) and p -cyano- ( 12 ) substituted compounds resulted in MOR partial agonists and DOR/KOR antagonists. By contrast, the derivatives 13 ⁻ 15 resulted as MOR antagonists, and the derivative 16 as a MOR/KOR antagonist (pK B MOR = 6.12 and pK B KOR = 6.11). Collectively, these data corroborated the critical role of the N -substituent in (−)- cis - N -Normetazocine scaffold. Thus, the new synthesized compounds could represent a template to achieve a specific agonist, antagonist, or mixed agonist/antagonist functional profile.

Anti-nociceptive interactions between opioids and a cannabinoid receptor 2 agonist in inflammatory pain

PubMed Central

Hale, David E; Guindon, Josée; Morgan, Daniel J

2017-01-01

The cannabinoid 1 receptor and cannabinoid 2 receptor can both be targeted in the treatment of pain; yet, they have some important differences. Cannabinoid 1 receptor is expressed at high levels in the central nervous system, whereas cannabinoid 2 receptor is found predominantly, although not exclusively, outside the central nervous system. The objective of this study was to investigate potential interactions between cannabinoid 2 receptor and the mu-opioid receptor in pathological pain. The low level of adverse side effects and lack of tolerance for cannabinoid 2 receptor agonists are attractive pharmacotherapeutic traits. This study assessed the anti-nociceptive effects of a selective cannabinoid 2 receptor agonist (JWH-133) in pathological pain using mice subjected to inflammatory pain using the formalin test. Furthermore, we examined several ways in which JWH-133 may interact with morphine. JWH-133 produces dose-dependent anti-nociception during both the acute and inflammatory phases of the formalin test. This was observed in both male and female mice. However, a maximally efficacious dose of JWH-133 (1 mg/kg) was not associated with somatic withdrawal symptoms, motor impairment, or hypothermia. After eleven once-daily injections of 1 mg/JWH-133, no tolerance was observed in the formalin test. Cross-tolerance for the anti-nociceptive effects of JWH-133 and morphine were assessed to gain insight into physiologically relevant cannabinoid 2 receptor and mu-opioid receptor interaction. Mice made tolerant to the effects of morphine exhibited a lower JWH-133 response in both phases of the formalin test compared to vehicle-treated morphine-naïve animals. However, repeated daily JWH-133 administration did not cause cross-tolerance for morphine, suggesting opioid and cannabinoid 2 receptor cross-tolerance is unidirectional. However, preliminary data suggest co-administration of JWH-133 with morphine modestly attenuates morphine tolerance. Isobolographic analysis revealed that co-administration of JWH-133 and morphine has an additive effect on anti-nociception in the formalin test. Overall these findings show that cannabinoid 2 receptor may functionally interact with mu-opioid receptor to modulate anti-nociception in the formalin test. PMID:28879802

Pharmacokinetics and pharmacodynamics of detomidine following sublingual administration to horses.

PubMed

Dimaio Knych, Heather K; Stanley, Scott D

2011-10-01

To characterize pharmacokinetics and pharmacodynamics of detomidine gel administered sublingually in accordance with label instructions to establish appropriate withdrawal guidelines for horses before competition. 12 adult racehorses. Horses received a single sublingual administration of 0.04 mg of detomidine/kg. Blood samples were collected before and up to 72 hours after drug administration. Urine samples were collected for 5 days after detomidine administration. Plasma and urine samples were analyzed via liquid chromatography-mass spectrometry, and resulting data were analyzed by use of noncompartmental analysis. Chin-to-ground distance, heart rate and rhythm, glucose concentration, PCV, and plasma protein concentration were also assessed following detomidine administration. Mean ± SD terminal elimination half-life of detomidine was 1.5 ± 1 hours. Metabolite concentrations were below the limit of detection (0.02, 0.1, and 0.5 ng/mL for detomidine, carboxydetomidine, and hydroxydetomidine, respectively) in plasma by 24 hours. Concentrations of detomidine and its metabolites were below the limit of detection (0.05 ng/mL for detomidine and 0.10 ng/mL for carboxydetomidine and hydroxydetomidine) in urine by 3 days. All horses had various degrees of sedation after detomidine administration. Time of onset was ≤ 40 minutes, and duration of sedation was approximately 2 hours. Significant decreases, relative to values at time 0, were detected for chin-to-ground distance and heart rate. There was an increased incidence and exacerbation of preexisting atrioventricular blocks after detomidine administration. A 48-hour and 3-day withdrawal period for detection in plasma and urine samples, respectively, should be adopted for sublingual administration of detomidine gel.

Pharmacokinetic-Pharmacodynamic Modeling of the Effect of Varenicline on Nicotine Craving in Adult Smokers

PubMed Central

Ravva, Patanjali; Gastonguay, Marc R.; Lee, Theodore C.; Niaura, Raymond

2015-01-01

Introduction: Varenicline has been shown to significantly reduce craving and several aspects of smoking reinforcement in clinical trials, compared with placebo. This is the first report describing the concentration-effect relationship of varenicline on relief of craving. Methods: The pharmacokinetics (PK) and pharmacodynamics (PD) of a single 2mg dose of varenicline were investigated in 40 smokers in a randomized, crossover study comparing the effect of varenicline with placebo on ameliorating abstinence-and cue-induced craving and withdrawal symptoms. Subjects were asked to complete self-reported questionnaires (Smoking Urges Scale and Minnesota Nicotine Withdrawal Scale [MNWS]) and blood samples were simultaneously collected for measurement of varenicline concentrations. Only the data from the 4-hr postdose abstinence period (just prior to the cue session) were analyzed. Data were described by a 2-compartment PK model and a linear PD model with first-order onset/offset rate constants describing the placebo response “kinetics.” Response was described as the net effect of the baseline, placebo, and drug responses. Results: Varenicline significantly decreased mean craving score when compared with placebo and the magnitude of this response was related to varenicline concentration. The time-course and magnitude of both placebo and varenicline craving response were characterized by a large degree of unexplained variability. Simulations were used to illustrate the expected craving response over time and its associated random variability after chronic dosing. Conclusions: Craving reduction is associated with increased varenicline concentrations. The relatively rapid onset of this effect within 4hr postdose suggests that, smokers may experience some craving relief after acute administration of varenicline. PMID:25145377

Clinical pharmacokinetics of non-opiate abused drugs.

PubMed

Busto, U; Bendayan, R; Sellers, E M

1989-01-01

The present review discusses the available data on the kinetic properties of non-opiate abused drugs including psychomotor stimulants, hallucinogens and CNS-depressants. Some of the drugs of abuse reviewed here are illicit drugs (e.g. cannabis, cocaine), while others are effective pharmacological agents but have the potential to be abused (e.g. benzodiazepines). Although some of the drugs mentioned in this review have been in use for centuries (e.g. caffeine, nicotine, cocaine, cannabis), knowledge of their kinetics and metabolism is very recent and in some cases still incomplete. This is partially due to the difficulties inherent in studying drugs of abuse in humans, and to the complex metabolism of some of these drugs (e.g. cannabis, caffeine) which has made it difficult to develop sensitive assays to determine biological pathways. Although drugs of abuse may have entirely different intrinsic pharmacological effects, the kinetic properties of such drugs are factors contributing to abuse and dependence. The pharmacokinetic properties that presumably contribute to self-administration and drug abuse include rapid delivery of the drug into the central nervous system and high free drug clearance. Kinetic characteristics also play an important role in the development of physical dependence and on the appearance of a withdrawal syndrome: the longer the half-life, the greater the likelihood of the development of physical dependence; the shorter the half-life, the earlier and more severe the withdrawal. The balance between these 2 factors, which has not yet been carefully studied, will also influence abuse patterns. The clinical significance of kinetic characteristics with respect to abuse is discussed where possible.

[Tapentadol: with two mechanisms of action in one molecule effective against nociceptive and neuropathic pain. Preclinical overview].

PubMed

Tzschentke, T M; Christoph, T; Schröder, W; Englberger, W; De Vry, J; Jahnel, U; Kögel, B Y

2011-02-01

Tapentadol (3-[(1R, 2R)-3-(dimethylamino)-1-ethyl-2-methylpropyl] phenol) is a centrally acting analgesic of a new substance class for the treatment of severe nociceptive and neuropathic pain. Tapentadol combines μ-opioid receptor (MOR) agonism and noradrenaline reuptake inhibition (NRI) in one molecule. Because of the combined mechanisms of action tapentadol offers a broad therapeutic spectrum for nociceptive as well as neuropathic pain. In different animal models its high efficacy was shown in acute nociceptive, acute and chronic inflammatory as well as in chronic neuropathic pain. Using several preclinical approaches it was shown that the noradrenergic component of tapentadol interacts with the opioid component and that both synergistically contribute to the analgesic effect of the substance. In comparison to known drugs with only one of the two modes of action, tapentadol, despite its high potency, has an improved tolerability profile in the relevant animal models, particularly with regard to gastrointestinal and central side effects. Tapentadol acts directly without metabolic activation and without formation of analgesically relevant metabolites. In different interaction studies a low potential for interactions was shown, thus clinically relevant drug-drug interactions are unlikely. Overall, tapentadol provides a safe pharmacodynamic-pharmacokinetic profile.

Altering ethanol pharmacokinetics to treat alcohol use disorder: can you teach an old dog new tricks?

PubMed Central

Haass-Koffler, Carolina L.; Akhlaghi, Fatemeh; Swift, Robert M.; Leggio, Lorenzo

2018-01-01

Disulfiram was the first pharmacotherapy approved to treat alcohol use disorder (AUD) in the 1950s. Disulfiram alters ethanol pharmacokinetics (PK) and causes uncomfortable reactions (e.g.: headache, tachycardia, nausea, flushing and hypotension) when alcohol is consumed. Subsequently, a better understanding of the neurobiological pathways involved in AUD led to the development of other medications (e.g.: naltrexone and acamprosate) to treat AUD. These neurobiological-based medications act on AUD-related phenotypes including craving, stress, and/or withdrawal. The original approach to treat AUD, by altering ethanol PK has been much less investigated. Recent research on ethanol PK has shed light on the mechanisms of action underlying AUD and how some medications that alter ethanol PK may be helpful in treating AUD. This review summarizes and discusses the complex PK of ethanol, and proposes that altering ethanol PK via novel pharmacological approaches may be a viable approach to treat AUD. PMID:28093021

A guide to benzodiazepine selection. Part II: Clinical aspects.

PubMed

Teboul, E; Chouinard, G

1991-02-01

To suit the specific needs of various clinical situations, selection of an appropriate benzodiazepine derivative should be based on consideration of their different pharmacokinetic and pharmacodynamic properties. Benzodiazepine derivatives that are rapidly eliminated produce the most pronounced rebound and withdrawal syndromes. Benzodiazepines that are slowly absorbed and slowly eliminated are most appropriate for the anxious patient, since these derivatives produce a gradual and sustained anxiolytic effect. Rapidly absorbed and slowly eliminated benzodiazepines are usually more appropriate for patients with sleep disturbances, since the rapid absorption induces sleep and the slower elimination rate may induce less tolerance to the sedative effect. Rational selection of a benzodiazepine for the elderly and for the suspected drug abuser is more problematic. The relevant pharmacokinetic and clinical considerations for these users are discussed. Certain derivatives may possess pharmacodynamic properties not shared by the entire benzodiazepine class; empirical studies have suggested the existence of anti-panic properties for alprazolam and clonazepam, antidepressant properties for alprazolam, and anti-manic properties for clonazepam and possibly lorazepam.

Chronic escalating cocaine exposure, abstinence/withdrawal, and chronic re-exposure: Effects on striatal dopamine and opioid systems in C57BL/6J mice

PubMed Central

Zhang, Yong; Schlussman, Stefan D.; Rabkin, Jacqui; Butelman, Eduardo R.; Ho, Ann; Kreek, Mary Jeanne

2013-01-01

Cocaine addiction is a chronic relapsing disease with periods of chronic escalating self-exposure, separated by periods of abstinence/withdrawal of varying duration. Few studies compare such cycles in preclinical models. This study models an “addiction-like cycle” in mice to determine neurochemical/molecular alterations that underlie the chronic, relapsing nature of this disease. Groups of male C57BL/6J mice received acute cocaine exposure (14-day saline/14-day withdrawal /13-day saline + 1-day cocaine), chronic cocaine exposure (14 day cocaine) or chronic re-exposure (14-day cocaine/14-day withdrawal /14-day cocaine). Escalating-dose binge cocaine (15-30 mg/kg/injection x 3/day, i.p. at hourly intervals) or saline (14-day saline) was administered, modeling initial exposure. In “re-exposure” groups, after a 14-day injection-free period (modeling abstinence/withdrawal), mice that had received cocaine were re-injected with 14-day escalating-dose binge cocaine, whereas controls received saline. Microdialysis was conducted on the 14th day of exposure or re-exposure to determine striatal dopamine content. Messenger RNA levels of preprodynorphin (Pdyn), dopamine D1 (Drd1) and D2 (Drd2) in the caudate putamen were determined by real-time PCR. Basal striatal dopamine levels were lower in mice after 14-day escalating exposure or re-exposure than in those in the acute cocaine group and controls. Pdyn mRNA levels were higher in the cocaine groups than in controls. Long-term adaptation was observed across the stages of this addiction-like cycle, in that the effects of cocaine on dopamine levels were increased after re-exposure compared to exposure. Changes in striatal dopaminergic responses across chronic escalating cocaine exposure and re-exposure are a central feature of the neurobiology of relapsing addictive states. PMID:23164614

The use of a food supplementation with D-phenylalanine, L-glutamine and L-5-hydroxytriptophan in the alleviation of alcohol withdrawal symptoms.

PubMed

Jukić, Tomislav; Rojc, Bojan; Boben-Bardutzky, Darja; Hafner, Mateja; Ihan, Alojz

2011-12-01

We described the use of a food supplementation with D-phenylalanine, L-glutamine and L-5-hydroxytriptophan in the alleviation of alcohol withdrawal symptoms in patients starting a detoxification therapy. Since abstinence from ethanol causes a hypodopaminergic and a hypoopioidergic environment in the reword system circuits, manifesting with withdrawal symptoms, food supplements that contains D-phenylalanine a peptidase inhibitor (of opioide inactivation) and L-amino-acids (for dopamine synthesis) were used to replenish a lack in neurotransmitters and alleviate the symptoms of alcohol withdrawal. 20 patients suffering from alcohol addictions starting a detoxification therapy have been included in a prospective, randomized, double blind study. The patients have been randomly devided in two groups. One group recieved for a period of 40 days a food supplement containing D-phenylalanine, L-glutamine and L-5-hydroxytriptophan (investigation group), and the control (placebo) group. On the first day of hospitalization the patients performed a SCL-90-R test, and blood samples were taken for measuring liver enzymes, total bilirubin, unbound cortisol and lymphocyte populations. The same was done on the 40th day of hospitalization. During the therapy a significant decrease in SCL-90-R psychiatric symptoms scores and a significant increase in CD4 lymphocyte count was observed in the investigation group. The cortisol values were significantly, but equally decreased in both groups, the same was with the liver enzymes and the total bilirubin values. We conclude that abstinence causes a major stress for the patients. The use of food supplement containing D-phenylalanine, L-glutamine and L-5-hydroxytriptophan alleviates the withdrawal symptoms and causes a rise in CD4 lymphocyte population, but it dose not affect the serum cortisol levels, which are probably more affected by liver inflammation and the liver restitution.

Kinetics and intrapulmonary disposition of tilmicosin after single and repeated oral bolus administrations to rabbits.

PubMed

Gallina, G; Lucatello, L; Drigo, I; Cocchi, M; Scandurra, S; Agnoletti, F; Montesissa, C

2010-06-01

Tilmicosin (TIM, Pulmotil) was administered to eight rabbits by oral gavage at a dose of 12.5 mg/kg body weight for 2, 5, and 7 days, and its plasma kinetics and intrapulmonary disposition were investigated. TIM concentrations in plasma samples collected after days 1 and 6 of treatment were measured by high-performance liquid chromatography with ultraviolet detection. The pharmacokinetic parameters, obtained by non-compartmental analysis of TIM plasma concentrations, did not show any significant variations between days 1 and 6. From the second day of treatment, TIM concentrations attained in lung tissue and pulmonary alveolar macrophages (PAM) exceeded those in plasma by 7- and 400-fold, respectively, and high levels were maintained in lung tissues during the entire treatment duration. After the first day of withdrawal, a fast decline in TIM levels in both plasma and lung tissue was observed, but in PAM, much higher concentrations were maintained after 3 days of TIM withdrawal.

Sedation in gastrointestinal endoscopy: current issues.

PubMed

Triantafillidis, John K; Merikas, Emmanuel; Nikolakis, Dimitrios; Papalois, Apostolos E

2013-01-28

Diagnostic and therapeutic endoscopy can successfully be performed by applying moderate (conscious) sedation. Moderate sedation, using midazolam and an opioid, is the standard method of sedation, although propofol is increasingly being used in many countries because the satisfaction of endoscopists with propofol sedation is greater compared with their satisfaction with conventional sedation. Moreover, the use of propofol is currently preferred for the endoscopic sedation of patients with advanced liver disease due to its short biologic half-life and, consequently, its low risk of inducing hepatic encephalopathy. In the future, propofol could become the preferred sedation agent, especially for routine colonoscopy. Midazolam is the benzodiazepine of choice because of its shorter duration of action and better pharmacokinetic profile compared with diazepam. Among opioids, pethidine and fentanyl are the most popular. A number of other substances have been tested in several clinical trials with promising results. Among them, newer opioids, such as remifentanil, enable a faster recovery. The controversy regarding the administration of sedation by an endoscopist or an experienced nurse, as well as the optimal staffing of endoscopy units, continues to be a matter of discussion. Safe sedation in special clinical circumstances, such as in the cases of obese, pregnant, and elderly individuals, as well as patients with chronic lung, renal or liver disease, requires modification of the dose of the drugs used for sedation. In the great majority of patients, sedation under the supervision of a properly trained endoscopist remains the standard practice worldwide. In this review, an overview of the current knowledge concerning sedation during digestive endoscopy will be provided based on the data in the current literature.

Sedation in gastrointestinal endoscopy: Current issues

PubMed Central

Triantafillidis, John K; Merikas, Emmanuel; Nikolakis, Dimitrios; Papalois, Apostolos E

2013-01-01

Diagnostic and therapeutic endoscopy can successfully be performed by applying moderate (conscious) sedation. Moderate sedation, using midazolam and an opioid, is the standard method of sedation, although propofol is increasingly being used in many countries because the satisfaction of endoscopists with propofol sedation is greater compared with their satisfaction with conventional sedation. Moreover, the use of propofol is currently preferred for the endoscopic sedation of patients with advanced liver disease due to its short biologic half-life and, consequently, its low risk of inducing hepatic encephalopathy. In the future, propofol could become the preferred sedation agent, especially for routine colonoscopy. Midazolam is the benzodiazepine of choice because of its shorter duration of action and better pharmacokinetic profile compared with diazepam. Among opioids, pethidine and fentanyl are the most popular. A number of other substances have been tested in several clinical trials with promising results. Among them, newer opioids, such as remifentanil, enable a faster recovery. The controversy regarding the administration of sedation by an endoscopist or an experienced nurse, as well as the optimal staffing of endoscopy units, continues to be a matter of discussion. Safe sedation in special clinical circumstances, such as in the cases of obese, pregnant, and elderly individuals, as well as patients with chronic lung, renal or liver disease, requires modification of the dose of the drugs used for sedation. In the great majority of patients, sedation under the supervision of a properly trained endoscopist remains the standard practice worldwide. In this review, an overview of the current knowledge concerning sedation during digestive endoscopy will be provided based on the data in the current literature. PMID:23382625

Wheel running during chronic nicotine exposure is protective against mecamylamine-precipitated withdrawal and up-regulates hippocampal α7 nACh receptors in mice.

PubMed

Keyworth, Helen; Georgiou, Polymnia; Zanos, Panos; Rueda, André Veloso; Chen, Ying; Kitchen, Ian; Camarini, Rosana; Cropley, Mark; Bailey, Alexis

2018-06-01

Evidence suggests that exercise decreases nicotine withdrawal symptoms in humans; however, the mechanisms mediating this effect are unclear. We investigated, in a mouse model, the effect of exercise intensity during chronic nicotine exposure on nicotine withdrawal severity, binding of α4β2*, α7 nicotinic acetylcholine (nAChR), μ-opioid (μ receptors) and D 2 dopamine receptors and on brain-derived neurotrophic factor (BDNF) and plasma corticosterone levels. Male C57Bl/6J mice treated with nicotine (minipump, 24 mg·kg -1 ·day -1 ) or saline for 14 days underwent one of three concurrent exercise regimes: 24, 2 or 0 h·day -1 voluntary wheel running. Mecamylamine-precipitated withdrawal symptoms were assessed on day 14. Quantitative autoradiography of α4β2*, α7 nAChRs, μ receptors and D 2 receptor binding was performed in brain sections of these mice. Plasma corticosterone and brain BDNF levels were also measured. Nicotine-treated mice undertaking 2 or 24 h·day -1 wheel running displayed a significant reduction in withdrawal symptom severity compared with the sedentary group. Wheel running induced a significant up-regulation of α7 nAChR binding in the CA2/3 area of the hippocampus of nicotine-treated mice. Neither exercise nor nicotine treatment affected μ or D 2 receptor binding or BDNF levels. Nicotine withdrawal increased plasma corticosterone levels and α4β2* nAChR binding, irrespective of exercise regimen. We demonstrated for the first time a profound effect of exercise on α7 nAChRs in nicotine-dependent animals, irrespective of exercise intensity. These findings shed light onto the mechanism underlining the protective effect of exercise on the development of nicotine dependence. This article is part of a themed section on Nicotinic Acetylcholine Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.11/issuetoc. © 2017 The British Pharmacological Society.

Human Abuse Potential of an Abuse-Deterrent (AD), Extended-Release (ER) Morphine Product Candidate (Morphine-ADER Injection-Molded Tablets) vs Extended-Release Morphine Administered Intranasally in Nondependent Recreational Opioid Users

PubMed Central

Webster, Lynn R.; Smith, Michael D.; Lawler, John; Lindhardt, Karsten; Dayno, Jeffrey M.

2017-01-01

Abstract Objective. To compare the relative human abuse potential after insufflation of manipulated morphine abuse-deterrent, extended-release injection-molded tablets (morphine-ADER-IMT) with that of marketed morphine ER tablets. Methods. A randomized, double-blind, double-dummy, active- and placebo-controlled five-way crossover study was performed with adult volunteers who were experienced, nondependent, recreational opioid users. After intranasal (IN) administration of manipulated high-volume (HV) morphine-ADER-IMT (60 mg), participants were randomized (1:1:1:1) to receive IN manipulated low-volume (LV) morphine ER (60 mg), IN manipulated LV morphine-ADER-IMT, intact oral morphine-ADER-IMT (60 mg), and placebo in crossover fashion. Pharmacodynamic and pharmacokinetic assessments included peak effect of drug liking (Emax; primary endpoint) using drug liking visual analog scale (VAS) score, Emax using overall drug liking, and take drug again (TDA) VASs scores, and mean abuse quotient (AQ), a pharmacokinetic parameter associated with drug liking. Results. Forty-six participants completed the study. After insufflation of HV morphine-ADER-IMT and LV morphine-ADER-IMT, drug liking Emax was significantly lower (P < 0.0001) compared with IN morphine ER. Overall drug liking and TDA Emax values were significantly lower (P < 0.0001) after insufflation of HV morphine-ADER-IMT and LV morphine-ADER-IMT compared with IN morphine ER. Mean AQ was lower after insufflation of HV (9.2) and LV (2.3) morphine-ADER-IMT or ingestion of oral morphine-ADER-IMT (5.5) compared with insufflation of LV morphine ER (37.2). Conclusions. All drug liking, take drug again, and abuse quotient endpoints support a significantly lower abuse potential with insufflation of manipulated morphine-ADER-IMT compared with manipulated and insufflated non-AD ER morphine. PMID:27651510

Human Abuse Potential of an Abuse-Deterrent (AD), Extended-Release (ER) Morphine Product Candidate (Morphine-ADER Injection-Molded Tablets) versus Extended-Release Morphine Administered Orally in Nondependent Recreational Opioid Users

PubMed Central

Webster, Lynn R.; Lawler, John; Lindhardt, Karsten; Dayno, Jeffrey M.

2017-01-01

Objective. To compare the relative human abuse potential of intact and manipulated morphine abuse-deterrent, extended-release injection-molded tablets (morphine-ADER-IMT) with that of marketed morphine sulfate ER tablets Methods. This randomized, double-blind, triple-dummy, active- and placebo-controlled, 4-way crossover, single-center study included adult volunteers who were experienced, nondependent, recreational opioid users. Participants were randomized 1:1:1:1 to placebo, morphine-ADER-IMT (60 mg, intact), morphine-ADER-IMT (60 mg, manipulated), and morphine ER (60 mg, manipulated) and received 1 dose of each oral agent in crossover fashion, separated by ≥5 days. Pharmacodynamic and pharmacokinetic endpoints were assessed, including the primary endpoint of peak effect of Drug Liking (Emax) via Drug Liking Visual Analog Scale (VAS) score and the secondary endpoints of time to Emax (TEmax) and mean abuse quotient (AQ; a pharmacokinetic parameter associated with drug liking). Results. Thirty-eight participants completed the study. Median Drug Liking VAS Emax was significantly lower after treatment with manipulated morphine-ADER-IMT (67) compared with manipulated morphine ER (74; P = 0.007). TEmax was significantly shorter after treatment with manipulated morphine ER compared with intact (P < 0.0001) or manipulated (P = 0.004) morphine-ADER-IMT. Mean AQ was lower after treatment with intact (5.7) or manipulated (16.4) morphine-ADER-IMT compared with manipulated morphine ER (45.9). Conclusions. Manipulated morphine-ADER-IMT demonstrated significantly lower Drug Liking Emax compared with manipulated morphine ER when administered orally. Morphine-ADER-IMT would be an important new AD, ER morphine product with lower potential for unintentional misuse by chewing or intentional manipulation for oral abuse than currently available non-AD morphine ER products. PMID:27633773

Review of clinical and laboratory experiences with molindone hydrochloride.

PubMed

Claghorn, J L

1985-08-01

The literature concerning the pharmacokinetics, pharmacodynamics, receptor physiology, and clinical use of molindone is reviewed. Unanswered questions about the drug are addressed. Although molindone is reputed to have a short half-life (1.5 hours), clinical observations report a prolonged effect from a once-daily dose. Early in treatment, some patients show intolerance due to akathisia or extrapyramidal symptoms. This may be withdrawal dyskinesia due to discontinuation of another drug or an early adverse effect of molindone. Different effects on dopamine receptors have been described, but the significance of these properties for the development of tardive dyskinesia remains unclear.

Pharmacokinetics of Understudied Drugs Administered to Children Per Standard of Care

ClinicalTrials.gov

2018-04-02

Adenovirus; Anesthesia; Anxiety; Anxiolysis; Autism; Autistic Disorder; Bacterial Meningitis; Bacterial Septicemia; Benzodiazepine; Bipolar Disorder; Bone and Joint Infections; Central Nervous System Infections; Convulsions; Cytomegalovirus Retinitis; Early-onset Schizophrenia Spectrum Disorders; Epilepsy; General Anesthesia; Gynecologic Infections; Herpes Simplex Virus; Infantile Hemangioma; Infection; Inflammation; Inflammatory Conditions; Intra-abdominal Infections; Lower Respiratory Tract Infections; Migraines; Pain; Pneumonia; Schizophrenia; Sedation; Seizures; Skeletal Muscle Spasms; Skin and Skin-structure Infections; Thromboprophylaxis; Thrombosis; Treatment-resistant Schizophrenia; Urinary Tract Infections; Withdrawal; Sepsis; Gram-negative Infection; Bradycardia; Cardiac Arrest; Cardiac Arrhythmia; Staphylococcal Infections; Nosocomial Pneumonia; Neuromuscular Blockade; Methicillin Resistant Staphylococcus Aureus; Endocarditis; Neutropenia; Headache

Increased Opioid Dependence in a Mouse Model of Panic Disorder

PubMed Central

Gallego, Xavier; Murtra, Patricia; Zamalloa, Teresa; Canals, Josep Maria; Pineda, Joseba; Amador-Arjona, Alejandro; Maldonado, Rafael; Dierssen, Mara

2009-01-01

Panic disorder is a highly prevalent neuropsychiatric disorder that shows co-occurrence with substance abuse. Here, we demonstrate that TrkC, the high-affinity receptor for neurotrophin-3, is a key molecule involved in panic disorder and opiate dependence, using a transgenic mouse model (TgNTRK3). Constitutive TrkC overexpression in TgNTRK3 mice dramatically alters spontaneous firing rates of locus coeruleus (LC) neurons and the response of the noradrenergic system to chronic opiate exposure, possibly related to the altered regulation of neurotrophic peptides observed. Notably, TgNTRK3 LC neurons showed an increased firing rate in saline-treated conditions and profound abnormalities in their response to met5-enkephalin. Behaviorally, chronic morphine administration induced a significantly increased withdrawal syndrome in TgNTRK3 mice. In conclusion, we show here that the NT-3/TrkC system is an important regulator of neuronal firing in LC and could contribute to the adaptations of the noradrenergic system in response to chronic opiate exposure. Moreover, our results indicate that TrkC is involved in the molecular and cellular changes in noradrenergic neurons underlying both panic attacks and opiate dependence and support a functional endogenous opioid deficit in panic disorder patients. PMID:20204153