Consumption of buprenorphine and other drugs among heroin addicts under ambulatory treatment: results from cross-sectional studies in 1988 and 1990

Patterns of use and adverse events reported among persons who regularly inject buprenorphine: a systematic review

BACKGROUND AND AIMS

Given the ongoing opioid crisis, novel interventions to treat severe opioid use disorder (OUD) are urgently needed. Injectable opioid agonist therapy (iOAT) with diacetylmorphine or hydromorphone is effective for the treatment of severe, treatment-refractory OUD, however barriers to implementation persist. Intravenous buprenorphine for the treatment of OUD (BUP iOAT) has several possible advantages over traditional iOAT, including a safety profile that might enable take-home dosing. We aimed to characterize injecting practices among real-world populations of persons who regularly inject buprenorphine, as well as associated adverse events reported in order to inform a possible future BUP iOAT intervention.

METHODS

We conducted a systematic review. We searched MEDLINE, EMBASE, and PsycINFO from inception through July 2020 and used backwards citation screening to search for publications reporting on dose, frequency among persons who regularly inject the drug, or adverse events associated with intravenous use of buprenorphine. The review was limited to English language publications and there was no limitation on study type. Study quality and risk of bias was assessed using the Mixed Methods Appraisal Tool. Narrative synthesis was used in reporting the results.

RESULTS

Eighty-eight studies were included in our review. Regular injection of buprenorphine was identified across diverse settings world-wide. Daily dose of oral buprenorphine injected was < 1-12 mg. Frequency of injection was 0-10 times daily. Adverse events could be characterized as known side effects of opioids/buprenorphine or injection-related complications. Most studies were deemed to be of low quality.

CONCLUSIONS

Extramedical, intravenous use of buprenorphine, continues to be documented. BUP iOAT may be feasible and results may inform the development of a study to test the efficacy and safety of such an intervention. Future work should also examine acceptability among people with severe OUD in North America. Our review was limited by the quality of included studies.

Fifty Years of Research on Prenatal Substances: Lessons Learned for the Opioid Epidemic

Current efforts to design research on developmental effects of prenatal opioid exposure can benefit from knowledge gained from 50 years of studies of fetal alcohol and prenatal drug exposures such as cocaine. Scientific advances in neurobiology, developmental psychopathology, infant assessments, genetics, and imaging support the principles of developmental neurotoxicology that guide research in prenatal exposures. Important to research design is accurate assessment of amount, frequency, and timing of exposure which benefits from accurate self-report and biomarkers of exposure. Identifying and control of pre- and postnatal factors that impact development are difficult and dependent on appropriate research design and selection of comparison groups and measurement of confounding, mediating, and moderating variables. Polysubstance exposure has increased due to the number of prescribed and nonprescribed substances used by pregnant women and varying combinations of drugs may have differential effects on the outcome. Multiple experimental and clinical assessments of infant behavior have been developed but predicting outcome before 18-24 months of age remains difficult. With some exceptions, prenatal substance exposure effect sizes have been small, and cognitive and behavioral effects tend to be specific rather than global. Studies require large sample sizes, adequate retention, and support for social services in at-risk samples. The ethical and legal contexts and stigma associated with drug/alcohol use disorder should be considered in order to prevent harm to families in research programs. Recognition of the pervasive use of addictive substances in this nation should lead to broad scientific efforts to understand how substances affect child outcomes and to initiate prevention and intervention where needed.

Challenges in implementing opioid agonist therapy in Lebanon: a qualitative study from a user's perspective

Background

Opioid agonist therapy (OAT) has been implemented for the treatment of individuals with opioid use disorders in Lebanon since 2011, but has not been evaluated yet. The aim of the study is to describe the implementation of the first pilot OAT program in Lebanon from the users’ perspective.

Methods

Data collectors gathered data from male participants during June 2016-July 2016. Eighty-one out of 94 patients agreed to participate in the study. Data regarding access to treatment, satisfaction with the treatment protocol and treatment outcomes, patient-provider relationship, and misuse and diversion was collected through semi-structured qualitative interviews. Data saturation was reached after 81 interviews; once no new themes were reported.

Results

Findings showed inequalities in access to treatment and showed that OAT improved mental and social wellbeing among users who had financial access and complied with the program protocols. Registering in the program protected users from arrest and reduced their economic burden. Among the main encountered challenges were fear of dependence to buprenorphine, restricted geographical access to treatment, misuse and diversion of buprenorphine.

Conclusion

Results implicate inequalities in access to OAT as one important gap to be tackled in the management of OAT in Lebanon. Further research should be done in order to understand the challenges in the implementation of the program from the providers’ perspectives.

Electronic supplementary material

The online version of this article (10.1186/s13011-018-0151-8) contains supplementary material, which is available to authorized users.

Impact of cannabis use during stabilization on methadone maintenance treatment

BACKGROUND AND OBJECTIVES

Illicit drug use, particularly of cannabis, is common among opiate-dependent individuals and has the potential to impact treatment in a negative manner.

METHODS

To examine this, patterns of cannabis use prior to and during methadone maintenance treatment (MMT) were examined to assess possible cannabis-related effects on MMT, particularly during methadone stabilization. Retrospective chart analysis was used to examine outpatient records of patients undergoing MMT (n = 91), focusing specifically on past and present cannabis use and its association with opiate abstinence, methadone dose stabilization, and treatment compliance.

RESULTS

Objective rates of cannabis use were high during methadone induction, dropping significantly following dose stabilization. History of cannabis use correlated with cannabis use during MMT but did not negatively impact the methadone induction process. Pilot data also suggested that objective ratings of opiate withdrawal decrease in MMT patients using cannabis during stabilization.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

The present findings may point to novel interventions to be employed during treatment for opiate dependence that specifically target cannabinoid-opioid system interactions.

Polydrug abuse: a review of opioid and benzodiazepine combination use

This paper reviews studies examining the pharmacological interactions and epidemiology of the combined use of opioids and benzodiazepines (BZDs). A search of English language publications from 1970 to 2012 was conducted using PubMed and PsycINFO(®). Our search found approximately 200 articles appropriate for inclusion in this paper. While numerous reports indicate that the co-abuse of opioids and BZDs is ubiquitous around the world, the reasons for the co-abuse of these medications are not entirely clear. Though the possibility remains that opioid abusers are using BZDs therapeutically to self-medicate anxiety, mania or insomnia, the data reviewed in this paper suggest that BZD use is primarily recreational. For example, co-users report seeking BZD prescriptions for the purpose of enhancing opioid intoxication or "high," and use doses that exceed the therapeutic range. Since there are few clinical studies investigating the pharmacological interaction and abuse liability of their combined use, this hypothesis has not been extensively evaluated in clinical settings. As such, our analysis encourages further systematic investigation of BZD abuse among opioid abusers. The co-abuse of BZDs and opioids is substantial and has negative consequences for general health, overdose lethality, and treatment outcome. Physicians should address this important and underappreciated problem with more cautious prescribing practices, and increased vigilance for abusive patterns of use.

Buprenorphine and buprenorphine/naloxone diversion, misuse, and illicit use: an international review

The diversion, misuse, and non-medically supervised use of buprenorphine and buprenorphine/naloxone by opioid users are reviewed. Buprenorphine and buprenorphine/naloxone are used globally as opioid analgesics and in the treatment of opioid dependency. Diversion of buprenorphine and buprenorphine/naloxone represents a complex medical and social issue, and has been widely documented in various geographical regions throughout the world. We first discuss the clinical properties of buprenorphine and its abuse potential. Second, we discuss its diversion and illicit use on an international level, as well as motivations for those activities. Third, we examine the medical risks and benefits of buprenorphine's non-medically supervised use and misuse. These risks and benefits include the effect of buprenorphine's use on HIV risk and the risk of its concomitant use with other medications and drugs of abuse. Finally, we discuss the implications of diversion, misuse, and non-medically supervised use (including potential measures to address issues of diversion); and potential areas for further research.

Thienorphine: receptor binding and behavioral effects in rhesus monkeys

Thienorphine is an oripavine with long-lasting antinociceptive effects in mice that are thought to be mediated by mu-opioid receptors. This study examined the receptor binding of thienorphine in cell membrane homogenates and its behavioral effects in rhesus monkeys (Macaca mulatta). Affinity and potency were determined using radioligand displacement and stimulation of guanosine 5'-O-(3-[35S]thio)triphosphate binding in C6 (mu, delta) and Chinese hamster ovary (kappa) cell membranes. Thienorphine displayed high affinity for kappa-, mu-, and delta-opioid receptors with K(i) values of 0.14, 0.22, and 0.69 nM, respectively. Thienorphine partially stimulated kappa-opioid (75%) and mu-opioid (19%) receptors and not delta-opioid receptors. Thienorphine dose-dependently increased tail-withdrawal latency for 50 degrees C water and not 55 degrees C water with effects lasting for more than 7 days. The kappa-opioid receptor antagonist nor-binaltorphimine (nor-BNI) (3.2 mg/kg) and a large dose (1.0 mg/kg) of naltrexone prevented thienorphine-induced antinociception. Thienorphine enhanced the antinociceptive effects of morphine and U50,488 [trans-3, 4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl]-benzeneacetamide] with 50 degrees C water; with 55 degrees C water, thienorphine enhanced the effects of morphine and attenuated the effects of U50,488. In other monkeys, thienorphine decreased responding in both components of a multiple schedule of food presentation and stimulus shock termination for up to 8 days; naltrexone and nor-BNI partially prevented these rate-decreasing effects. In morphine-treated monkeys discriminating naltrexone, thienorphine, and U50,488 neither substituted for nor modified the naltrexone discriminative stimulus. Thienorphine and U50,488 produced the same directly observable signs. These results show that thienorphine has long-lasting effects that seem to be mediated by low-efficacy agonism at kappa-opioid receptors, both in vitro and in vivo.

Buprenorphine-containing treatments: place in the management of opioid addiction

Although the synthetic opioid buprenorphine has been available clinically for almost 30 years, its use has only recently become much more widespread for the treatment of opioid addiction. The pharmacodynamic and pharmacokinetic profiles of buprenorphine make it unique in the armamentarium of drugs for the treatment of opioid addiction. Buprenorphine has partial mu-opioid receptor agonist activity and is a kappa-opioid receptor antagonist; hence, it can substitute for other micro-opioid receptor agonists, yet is less apt to produce overdose reactions or dysphoria. On the other hand, buprenorphine can block the effects of opioids such as heroin (diamorphine) and morphine, and can even precipitate withdrawal in individuals physically dependent upon these drugs. Buprenorphine has significant sublingual bioavailability and a long half-life, making administration on a less than daily basis possible. Furthermore, its discontinuation is associated with only a mild withdrawal syndrome. Clinical trials have demonstrated that sublingual buprenorphine is effective in both maintenance therapy and detoxification of individuals addicted to opioids. The introduction of a sublingual formulation combining naloxone with buprenorphine further reduces the risk of diversion to illicit intravenous use. Because of its relative safety and lower risk of illegal diversion, buprenorphine has been made available in several countries for treating opioid addiction in the private office setting, greatly enhancing treatment options for this condition.

Alprazolam-Related Deaths in Palm Beach County

Alprazolam is a commonly prescribed benzodiazepine. The abuse of benzodiazepines is most frequently seen in conjunction with the abuse of other drugs. Only rare fatalities have been attributed to alprazolam alone. We undertook a retrospective review of cases investigated by the Palm Beach County Medical Examiner's Office in which postmortem toxicologic studies indicated the presence of alprazolam, to further study the pattern of alprazolam abuse. Our review consisted of 178 cases, including 87 in which death was attributed to combined drug toxicity, 2 to alprazolam toxicity alone, 44 to trauma, 12 to natural causes, and 33 to another drug or drugs. Cocaine and methadone were the most common cointoxicants in the cases of combined drug toxicity, while heroin was less frequently detected. There was considerable overlap in the postmortem blood alprazolam concentrations among the groups. The overlapping ranges of concentrations of alprazolam detected indicate that it may be difficult to define a lethal alprazolam range, and that it may not be possible to determine the actual role of alprazolam as a causal factor in cases of combined drug toxicity. This study confirms that alprazolam alone is rarely a cause of death, and that alprazolam abuse usually occurs within a polydrug use pattern. The high incidence of cocaine as a cointoxicant has not been previously reported.

Buprenorphine diversion and injection in Melbourne, Australia: an emerging issue?

AIMS

To examine indicators of buprenorphine diversion and injection among injecting drug users in Melbourne, Australia and to determine the factors associated with buprenorphine injection.

DESIGN

Melbourne arm of the 2002 Illicit Drug Reporting System (IDRS) cross-sectional study.

SETTING

Five Needle and Syringe Programme sites in Melbourne, Australia.

PARTICIPANTS

A total of 156 current injecting drug users (IDU). Study eligibility criteria were at least monthly injection during the previous 6 months, and Melbourne residence for at least the preceding 12 months.

MEASUREMENTS

Structured questionnaire covering demographic characteristics, drug use history, the price, purity and availability of drugs, criminal activity, risk-taking behaviours, health-related issues and general drug use trends.

FINDINGS

Over one-third (37%) of the study sample reported injecting buprenorphine in their life-time and 33% reported injecting the drug in the last 6 months. Recent buprenorphine injection was associated with the injection of other drug types (i.e. polydrug injectors), opioid substitution treatment, injection-related health problems and involvement in crime. Almost half (47%) of those who reported recent buprenorphine injection reported obtaining the drug illicitly at least once during that time.

CONCLUSIONS

Given the significant health harms associated with intravenous buprenorphine use (e.g. vein damage, abscesses and infections, precipitated withdrawal, blood-borne virus transmission, hospitalization and death), routine monitoring of the misuse of buprenorphine in Melbourne is warranted. These results suggest the need for development of effective countermeasures to address diversion and injection of buprenorphine in this setting.

Effects of high-dose intravenous buprenorphine in experienced opioid abusers

Sublingual buprenorphine, a long-acting, partial mu-opioid agonist, is as effective as methadone in the treatment of heroin dependence, with a better safety profile due to its antagonist activity. However, the safety of therapeutic doses (8 to 16 mg) that might be diverted for intravenous (i.v.) use has not been demonstrated. To evaluate the safety and possible ceiling effects of buprenorphine administered i.v. to experienced opioid users, buprenorphine was administered to 6 nondependent opioid abusers residing on a research unit; the doses tested, in separate sessions, were 12 mg buprenorphine sublingual, i.v./sublingual placebo, and escalating i.v. buprenorphine (2, 4, 8, 12, and 16 mg). Physiologic and subjective measures were collected for 72 hours post-drug administration. Buprenorphine minimally but significantly increased systolic blood pressure. Changes in heart rate or oxygen saturation among the 7 drug conditions were not statistically significant. The mean maximum decrease in oxygen saturation from baseline was greatest for the 8-mg i.v. dose. Buprenorphine produced positive mood effects, although with substantial variability among participants. Onset and peak effects occurred earlier following i.v. administration: peak i.v. effects occurred between 0.25 and 3 hours; peak sublingual effects occurred at 3 to 7 hours. Duration of effects varied among the outcome measures. The dose-response curves were flat for most parameters, particularly subjective measures. Side effects were mild except in one participant who experienced severe nausea and vomiting after the 12-mg i.v. dose. Buprenorphine appears to have a ceiling for cardiorespiratory and subjective effects and a high safety margin even when taken by the i.v. route.

Serious overdoses involving buprenorphine in Helsinki

BACKGROUND

Buprenorphine is used as maintenance therapy for opioid-dependent patients. In comparison with other opioids it is thought to be safer because it is less likely to cause serious respiratory depression. However, concomitant use of psychotropics, especially benzodiazepines, and intravenous injection of dissolved buprenorphine tablets increase the risk of a serious overdose.

METHODS

As part of a larger retrospective study of opioid overdoses in Helsinki, the emergency medical services (EMS) records from January 1995 to April 2002 were reviewed for overdoses involving buprenorphine. Hospital records were reviewed when available.

RESULTS

We report 11 overdoses in which buprenorphine was involved. The classic symptoms and signs of an opioid overdose (respiratory depression, miosis and central nervous system depression) were present in most of the cases. At least eight of the patients had an overdose that was potentially fatal. One of the patients had a heroin overdose and was reportedly 'treated' by his friends with intravenously administered buprenorphine.

CONCLUSION

The high-dosage formulation of buprenorphine used for opioid-dependent patients might have caused several dangerous and potentially fatal overdoses in Helsinki. However, it does cause considerably less serious overdoses than heroin. Drug abusers might be intravenously administering buprenorphine themselves to treat heroin overdoses.

Antinociceptive activity of a novel buprenorphine analogue

HS-599 is a didehydroderivative of buprenorphine that displays high affinity and good selectivity for mu-opioid receptors. We studied its antinociceptive properties after s.c. injection in mice with the tail-flick and hot-plate tests. In the tail-flick test HS-599 (AD50 = 0.2801 micromol/kg s.c.) behaved as a full agonist and was twice as potent as buprenorphine (AD50=0.4569 micromol/kg s.c.) and 50 times more potent than morphine (AD50 = 13.3012 micromol/kg s.c.). Whereas the mu-opioid receptor antagonists naloxone (1-10 mg/kg s.c.) and naltrexone (5-15 mg/kg s.c.) antagonized HS-599 induced analgesia, the delta-opioid receptor antagonist naltrindole (20 mg/kg s.c.) and the kappa-opioid receptor antagonist nor-binaltorphimine (20 mg/kg s.c.) did not. With the hot-plate test at 50 degrees C, HS-599 (AD50 = 0.0359 micromol/kg s.c.) was a full agonist about 130 times more potent than morphine (AD50 = 4.8553 micromol/kg s.c.). With a high intensity nociceptive stimulus (55 degrees C) HS-599 (AD50 = 1.0382 micromol/kg s.c.) remained 7 times more potent than morphine (AD50 = 7.0210 micromol/kg s.c.) but never exceeded the 55% of the maximum possible effect, behaving as a partial agonist able to antagonize morphine antinociception in a dose-dependent manner. HS-599 promises to be a potent and safe new analgesic, preferentially acting at spinal level.

Modulation of rate of onset and intensity of drug effects reduces abuse potential in healthy males

Low, medium, and high doses of flunitrazepam were tested in three independent randomized, double-blind, balanced cross-over, placebo-controlled trials to study the influence of rate of onset of effects and dose administered on its acute effects. Three groups of 12 healthy male volunteers received six oral doses of placebo or flunitrazepam in slow and fast onset conditions as follows: six capsules of 0.16 mg (slow) and a single capsule of 0.8 mg (fast) in the low dose trial; six 0.25 mg (slow) and a single 1.25 mg (fast) capsules for medium dose; and six 0.4 mg (slow) and a single 2 mg (fast) capsule for high dose. At each dose level, slow or fast increasing flunitrazepam plasma concentrations lead to similar peak levels, but induced differential subjective and behavioral effects. In addition to objective and subjective sedation, flunitrazepam induced some pleasurable feelings, which were more intense in the fast than in the slow conditions. At the highest dose, unpleasant sedative effects surmounted positive effects, while at the lowest dose pleasurable effects were of low intensity. At the medium dose, the balance between pleasurable and unpleasant feelings resulted in euphorigenic effects, which were evident in the fast condition but were blunted in the slow condition.

HS-599: a novel long acting opioid analgesic does not induce place-preference in rats

1. When administered subcutaneously HS-599, a new didehydroderivative of buprenorphine (18,19-dehydrobuprenorphine), produced a long-lasting antinociceptive response in rats. Its potency exceeded twice that of buprenorphine. In the tail-flick test it acted as a full agonist but in the plantar test only as a partial agonist. Whereas the mu-opioid antagonists naloxone and naltrexone antagonized HS-599 antinociception the delta-opioid antagonist naltrindole and the kappa-opioid antagonist nor-binaltorphimine did not. 2. Unlike buprenorphine and morphine, HS-599 never induced conditioned place-preference in rats. 3. In radioligand binding assays, compared with buprenorphine HS-599 had 3 fold higher mu-opioid receptor affinity but lower delta- and kappa-opioid receptor affinity. 4. In isolated guinea-pig ileum preparations, HS-599 only partially inhibited the electrically-stimulated contraction, acting as a partial opioid agonist. When tested against the mu-opioid receptor agonist dermorphin, it behaved as a non-equilibrium antagonist. Conversely, in mouse vas deferens (rich in delta-opioid receptors) and rabbit vas deferens preparations (rich in kappa-opioid receptors) HS-599 acted as a pure equilibrium antagonist, shifting the log-concentration-response curves of the delta-opioid agonist deltorphin I and the kappa-opioid agonist U-69593 to the right. 5. In conclusion, HS-599 is a novel buprenorphine derivative with higher affinity, selectivity and potency than the parent compound, for mu-opioid receptors. It produces intense and long-lasting antinociception and does not induce place-preference in rats.

Buprenorphine: "field trials" of a new drug

Buprenorphine is being introduced as a new treatment drug for narcotics addiction in the United States. The authors were asked by the National Institute on Drug Abuse to conduct a field trial to determine if buprenorphine might play a role in street markets. Because no street use of the drug existed in the United States, the authors used three sources of information: (a) "street readings" of clinical studies, (b) Internet discussion lists, and (c) research in other countries. By using an emergent style of analysis that relies on replication of patterns across disparate data sources, it was determined that buprenorphine has desirable characteristics from a street addict point of view. An evaluation of the field trial 5 years later evaluates its accuracy.

Influence of buprenorphine, butorphanol and nalbuphine on the initiation of intravenous cocaine self-administration in drug naive mice

The influence of different mixed mu-kappa-opioid receptor agonists-antagonists on cocaine reinforcement was studied using the method of initiation of intravenous cocaine self-administration in naive mice. Self-administration of cocaine was readily initiated according to an inverted U-shaped unit dose-response curve. Buprenorphine, butorphanol and nalbuphine tested against the optimal unit dose of cocaine (0.8 microg per infusion), inhibited initiation of cocaine self-administration in a dose-dependent manner. When tested against a scale of cocaine unit doses (0.2 -1.6 microg per infusion) buprenorphine (0.1 mg/kg, s.c.) and nalbuphine (2 mg/kg, s. c.) produced a shift of the optimal cocaine dose from 0.8 to 0.4 microg/inf, while butorphanol (1 mg/kg, s.c.) shifted the optimal unit dose of cocaine to the right along the cocaine unit doses axis. Co-administration of naloxone (0.1 mg/kg, s.c.) significantly reduced the effect of buprenorphine but failed to influence the effect of nalbuphine and butorphanol on cocaine intake. Taken together, these results suggest that nalbuphine is capable of affecting cocaine's reinforcing properties in the same manner as buprenorphine during the initiation phase of cocaine self-administration behavior, while butorphanol causes the opposite effect. Although the exact opioid profile of action of the mixed opioid receptor agonists-antagonists is as yet not precisely known, the present findings suggest that multiple opioid receptor systems (i.e. mu and kappa) play a role in reinforcing properties of cocaine and that a co-operative interaction between mu- and kappa-opioid systems may be of importance during initiation of cocaine self-administration.

Effects of buprenorphine on motility in morphine post-dependent rats

The effects of buprenorphine (0.0125-0.2 mg kg(-1)) on the locomotor activity of rats were determined 1-2 months after ceasing a chronic treatment with morphine (20 mg kg(-1)for 28 days). In control animals buprenorphine exhibited both depressive and stimulatory actions, as repeatedly described for morphine. In post-dependent animals buprenorphine showed a depressive effect similar to that observed in naive ones. On the contrary, a persistent sensitization to the excitatory effect was observed; the degree of cross-sensitization was similar to that of morphine itself (20 mg kg(-1)). The results are discussed in terms of persistent changes in the locomotor response to opioids, possibly correlated to both drug craving and relapse.

Monitoring patterns of substance use in drug-dependent patients

Drug-addicted patients (N = 435) admitted for treatment in different clinical settings were studied. Patients were classified according to their self-report of consumed drugs and to the results of urine screening tests. Of the patients, 77.8% were active consumers, 9.6% were included in a methadone maintenance program, and 12.6% were abstinent. In the active consumer patients, positive urine screening results surpassed by far the information provided in the self-reports. Most patients tested positive to several drugs, while only 8.7% tested negative to all screened drugs. These results indicate that the information provided by drug-dependent patients lacks reliability when an analytical screening method is used simultaneously.