Nonmedical Use of Antihistaminergic Anxiolytics and Other Prescription Drugs among Persons with Opioid Dependence

Substance Use, Hospitalizations, and Co-Occurring Disorders among Patients Transferred from a Needle Exchange Program to Opioid Maintenance Treatment

Opioid use disorders (OUD) is a relapsing condition with high mortality. Opioid maintenance treatment (OMT) reduces heroin use, and overall morbidity and mortality. The prevalence of psychiatric and substance use disorders, potential baseline predictors for psychiatric hospitalization, and psychiatric diagnoses at follow-up were investigated and may give hints about possible preventative strategies. The medical records for 71 patients were reviewed 36 months following referral to OMT from a needle exchange program (NEP). Their psychiatric diagnoses and hospitalizations were identified. Their baseline characteristics were assessed for potential differences between hospitalized versus non-hospitalized patients and between patients with and without psychiatric diagnoses in a longitudinal observational study without controls. A regression analysis was performed to identify predictors for hospitalization when controlling for OMT status. Sixty-five percent of the patients were hospitalized at least once with a psychiatric diagnosis. Substance-related reasons were prevalent, and detoxification occurred among 59% of patients, with sedative- hypnotics (benzodiazepines, zopiclone, zolpidem, and pregabalin) being the substance used by 52% of patients. Baseline use of these drugs and/or buprenorphine predicted for hospitalization when controlling for OMT status. During the follow-up period, 72% of patients met the criteria for a psychiatric diagnosis other than OUD. The prevalence of non-substance use disorders overlapping with SUD was 41%, and that overlapping with anxiety disorder was 27% of all participants. Increased attention to psychiatric co-occurring disorders in the treatment of OUD is required and the importance of addressing sedative-hypnotics use when initiating OMT is highlighted.

Gabapentinoid Pharmacology in the Context of Emerging Misuse Liability

This article will review the epidemiology and pharmacology of gabapentinoids (gabapentin and pregabalin) relevant to their emerging misuse potential and provide guidance for clinical and regulatory management. Gabapentinoids are γ-aminobutyric acid analogues that produce their therapeutic effects by inhibiting voltage-gated calcium channels and decreasing neurotransmitter release. Recently gabapentinoid prescribing and use have increased tremendously. Although traditionally thought to possess a favorable safety profile, gabapentinoid misuse has also risen significantly. Gabapentinoid misuse generally occurs in combination with other substances, most notably opioids, and may be for purposes of eliciting euphoric effects, enhancing the effects of other substances, or self-treating conditions such as withdrawal, pain, anxiety, or insomnia. Given its faster onset, increased bioavailability and potency, and nonsaturable absorption, pregabalin's pharmacokinetics theoretically enhance its misuse liability versus gabapentin. However, gabapentin can produce similar euphoric effects, and epidemiologic studies have identified higher rates of gabapentin misuse in the United States, likely because of greater availability and less regulated prescribing. Although adverse events of gabapentinoid-only ingestion are relatively benign, a growing body of evidence indicates that gabapentinoids significantly increase opioid-related morbidity and mortality when used concomitantly. In addition, significant withdrawal effects may occur on abrupt discontinuation. As a result of these trends, several US states have begun to further regulate gabapentinoid prescribing, reclassifying it as a controlled substance or mandating reporting to local prescription drug-monitoring programs. Although increased regulation of gabapentin prescribing may be warranted, harm reduction efforts and increased patient and provider education are necessary to mitigate this concerning gabapentinoid misuse trend.

Beyond the 'purple drank': Study of promethazine abuse according to the European Medicines Agency adverse drug reaction reports

BACKGROUND

Promethazine is a medicinal product, available on its own or in combination with other ingredients including dextromethorphan, paracetamol and/or expectorants. Anecdotal reports have however indicated that promethazine may have a misuse potential, especially in adolescents.

OBJECTIVE

We here aimed at studying how this phenomenon has been reported to the European Monitoring Agency Adverse Drug Reactions database.

METHODS

After a formal request to the European Monitoring Agency, the promethazine-specific dataset has been studied, performing a descriptive analysis of misuse/abuse/dependence-related adverse drug reaction reports. The study was approved by the University of Hertfordshire (LMS/PGR/UH/03234).

RESULTS

The analysis of promethazine data showed increasing levels of misuse/abuse/ dependence issues over time (2003-2019). Out of a total number of 1543 cases of adverse drug reactions, the abuse/misuse/dependence-related cases reported were 557, with 'drug abuse' (300/557: 53.8%) and 'intentional product misuse' (117/557: 21.0%). being the most represented adverse drug reactions. A high number of fatalities were described (310/557: 55.6%), mostly recorded as 'drug toxicity/drug abuse' cases, with opiates/opioids having been the most commonly reported concomitant drugs used.

CONCLUSION

Anecdotal promethazine misuse/abuse reports have been confirmed by European Monitoring Agency data. Promethazine misuse/abuse appears to be an alarming issue, being associated with drug-related fatalities. Thus, healthcare professionals should be warned about a possible misuse of promethazine and be vigilant, as in some countries medicinal products containing promethazine can be purchased over the counter. Since promethazine is often available in association with opioids, its abuse may be considered a public health issue, with huge implications for clinical practice.

Focus on Over-the-Counter Drugs' Misuse: A Systematic Review on Antihistamines, Cough Medicines, and Decongestants

Background: Over the past 20 years or so, the drug misuse scenario has seen the emergence of both prescription-only and over-the-counter (OTC) medications being reported as ingested for recreational purposes. OTC drugs such as antihistamines, cough/cold medications, and decongestants are reportedly the most popular in being diverted and misused. Objective: While the current related knowledge is limited, the aim here was to examine the published clinical data on OTC misuse, focusing on antihistamines (e.g., diphenhydramine, promethazine, chlorpheniramine, and dimenhydrinate), dextromethorphan (DXM)- and codeine-based cough medicines, and the nasal decongestant pseudoephedrine. Methods: A systematic literature review was carried out with the help of Scopus, Web of Science databases, and the related gray literature. For data gathering purposes, both the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and PROSPERO guidelines were followed (PROSPERO identification code CRD42020209261). Results: After completion of the selection, eligibility, and screening phases, some 92 articles were here taken into consideration; case reports, surveys, and retrospective case series analyses were included. Findings were organized according to the specific OTC recorded. Most articles focused here on DXM (n = 54) and diphenhydramine (n = 12). When specified, dosages, route(s) of administration, toxicity symptoms (including both physical and psychiatric ones), and outcomes were here reported. Conclusion: Results from the systematic review showed that the OTC misusing issues are both widespread worldwide and popular; vulnerable categories include adolescents and young adults, although real prevalence figures remain unknown, due to a lack of appropriate monitoring systems. Considering the potential, and at times serious, adverse effects associated with OTC misusing issues, healthcare professionals should be vigilant, and ad hoc preventative actions should be designed and implemented.

Abuse and Misuse of Pregabalin and Gabapentin: A Systematic Review Update

BACKGROUND

A 2017 systematic review (SR) identified 59 studies examining gabapentinoid (pregabalin and gabapentin) misuse/abuse. Evidence of gabapentinoid misuse/abuse has since grown substantially.

OBJECTIVE

Update previous SR and describe new insights regarding gabapentinoid abuse.

METHODS

A SR of PubMed was conducted to identify studies published from 7/29/2016-8/31/2020. Four searches were performed using the following terms: "gabapentin [MeSH] OR pregabalin [MeSH] OR gabapentinoid" AND one of the following substance misuse/abuse-related terms: "substance-related disorders [MeSH]", "overdose", "abuse", or "misuse". Clinicaltrials.gov and the Cochrane Library database were searched to identify ongoing studies or similar SRs. Reference lists of included studies were reviewed to identify additional literature. All studies with novel data related to pregabalin and/or gabapentin abuse, misuse, or overdose conducted during the study period were included. Articles not written in English, review articles, and animal studies were excluded.

RESULTS

Fifty-five studies were included (29 [52.7%] from North America, 17 [30.9%] Europe, 6 [10.9%] Asia, and 3 [5.5%] Australia). Forty-six observational studies and 10 case reports/series were included (one manuscript included both). Twenty (36.4%) studied gabapentin only, 18 (32.7%) pregabalin only, and 17 (30.9%) both pregabalin/gabapentin. These studies corroborate findings from the previous SR that gabapentinoids are increasingly abused or misused to self-medicate, that gabapentinoids can produce desirable effects alone but are often used concomitantly with other drugs, and that opioid use disorder is the greatest risk factor for gabapentinoid abuse. While the original SR identified the largest studies having been published in Europe, this review identified several more generalisable US studies that have subsequently been conducted. The most concerning finding was increased evidence of associated patient harm, including increased hospital utilisation and opioid-related overdose mortality risk.

CONCLUSION

Evidence suggests that gabapentinoid misuse/abuse represents a growing trend that is causing significant patient harm. Prescribers should exercise appropriate caution with use in high-risk populations and monitor for signs of misuse or abuse.

Nonmedical use of benzodiazepines and Z-drugs in the UK

AIMS

To estimate prevalence of last 12-month nonmedical use (NMU) of benzodiazepines and Z-drugs (the nonbenzodiazepine hypnotics zaleplon, zolpidem and zopiclone) in the UK.

METHODS

Data were collected using the Non-Medical Use of Prescription Drugs survey with poststratification weighting applied to be representative of the UK population (≥16 years). Participants were questioned about whether they had nonmedically used benzodiazepines and/or Z-drugs in the last 12-months and from where they had obtained the drug (including via a prescription, or illicitly from a friend/family member, a dealer or via the internet). Additional questions were asked about last 12-month use of illicit drugs (cannabis, cocaine, 3,4-methylenedioxymethylamphetamine [MDMA], non-pharmaceutical amphetamine, crack cocaine and/or heroin).

RESULTS

The study included 10 006 eligible participants representing approximately 52 927 000 UK adults. The estimated prevalence of past 12-month NMU of any benzodiazepine and/or Z-drug was 1.2% (95% confidence interval: 1.0-1.5) corresponding to approximately 635 000 adults; amongst this group only an estimated 4.6% (1.2-8.0) had NMU of both a benzodiazepine and a Z-drug. The highest prevalence of NMU for only Z-drugs was among those who had used heroin in the last 12-months (5.4%, 2.7-10.5), whilst the highest prevalence of NMU for only benzodiazepines was among those who had used illicit stimulants in the last 12-months: cocaine (5.9%, 3.8-8.9), amphetamine (5.6%, 3.1-10.0) and MDMA (5.2%, 3.1-8.8). The drug non-medically used was more commonly acquired without than with a prescription for both only benzodiazepines (70.2%, 59.4-81.1 compared to 51.3%, 41.5-64.6) and only Z-drugs (75.6%, 61.6-89.7 compared to 33.9%, 16.9-51.0).

CONCLUSION

There is little overlap between benzodiazepine and Z-drug NMU suggesting distinct nonmedical use of the drugs; future studies need to explore whether this relates to personal preference, drug availability or other factors. A significant proportion are acquiring these drugs for NMU without a prescription, so without guidance and monitoring from a medical practitioner. While the dangers of mixing benzodiazepines and heroin/other opioids are well documented, there is a paucity of data regarding concomitant NMU of benzodiazepines and stimulant drugs, or NMU of Z-drugs and opioids, and, given the prevalence of these combinations, this requires further investigation.

Concomitant drug abuse of opioid dependent patients in maintenance treatment detected with a multi-target screening of oral fluid

BACKGROUND AND OBJECTIVES

Numbers of drug-related deaths have been growing in Europe and the USA, especially those attributable to mixed drug consumption. Overdose deaths account for about one third up to one half of all illicit drug deaths worldwide. In most cases opioids are involved. Opioid maintenance treatment (OMT) is a well-established therapy option among people with opioid dependence. The aim of this study was to assess concomitant substance abuse in opioid-dependent patients under OMT in two centers in Munich, Germany.

METHODS

Oral fluid samples of opioid-dependent patients (n = 388) in OMT were randomly collected and analyzed by a multi-drug screening covering a wide range of psychotropic agents with UPLC-MS/MS techniques.

RESULTS

Fifty-one percent of the patients had concomitant substance abuse of at least one non-prescribed substance, 32% were positive for substances that were not tested in routine urine diagnostics, especially pregabalin. Fifty-seven percent received take-home opioid medication, and 26% had contact with underage children. Among the take-home subgroup, a concomitant substance abuse of 43.5% was detected. Furthermore 52.5% of the patients with contact to underaged children exhibited concomitant substance abuse.

CONCLUSIONS

Concomitant substance abuse is a serious issue among OMT patients. Screening for a broader range of substances than usually analyzed, reveals additional relevant abuse among OMT patients, including pregabalin-an anticonvulsant.

SCIENTIFIC SIGNIFICANCE

Our study underscores the importance of monitoring a broad range of substances including others than usually screened in opioid-dependent patients in OMT. (Am J Addict 2018;XX:1-6).

High Rates of Tramadol Use among Treatment-Seeking Adolescents in Malmö, Sweden: A Study of Hair Analysis of Nonmedical Prescription Opioid Use

Background

Nonmedical prescription opioid use (NMPOU) is a growing problem and tramadol has been suggested as an emerging problem in young treatment-seeking individuals. The aim of the present study was to investigate, through hair analysis, NMPOU in this group and, specifically, tramadol use.

Methods

In a study including 73 treatment-seeking adolescents and young adults at an outpatient facility for young substance users, hair specimens could be obtained from 59 subjects. Data were extracted on sociodemographic background variables and psychiatric diagnoses through MINI interviews.

Results

In hair analysis, tramadol was by far the most prevalent opioid detected. Thirty-two percent screened positive for opioids, and of those, all but one were positive for tramadol. Ninety-eight percent reported problematic cannabis use. Significantly more opioid-positive patients also screened positive for other (noncannabis) drugs, compared to nonopioid users. Sixty-four percent fulfilled criteria of DSM-IV psychiatric disorders, other than substance use disorders according to MINI. Fifty-three percent met the symptom criteria count of ADHD above cut-off level.

Conclusion

In the present setting, tramadol, along with high rates of cannabis use, may represent a novel pattern of substance use among young treatment-seeking subjects with problematic substance use and high rates of concurrent psychiatric problems.