Fatalities associated with gabapentinoids in England (2004-2020)

The gabapentinoids were reclassified as Schedule II medications and Class C drugs in the UK in 2019 due to their potential misuse. In this study we examined deaths following gabapentinoid use in England reported to the National Programme on Substance Abuse Deaths.

A total of 3051 deaths were reported (gabapentin: 913 cases; pregabalin: 2322 cases [both detected in 184 cases]). Prescribed and illicitly obtained gabapentinoids accounted for similar proportions of deaths (gabapentin illicit 38.0%, prescribed 37.1%; pregabalin illicit 41.0%, prescribed 34.6%). Opioids were co‐detected in most cases (92.0%), and co‐prescribed in a quarter (25.3%). Postmortem blood gabapentinoid concentrations were commonly (sub)therapeutic (65.0% of gabapentin cases; 50.8% of pregabalin cases). In only two cases was gabapentinoid toxicity alone attributed in causing death.

Gabapentinoids alone rarely cause death. Clinically relevant doses can, however, prove fatal, possibly by reducing tolerance to opioids. Doctors and patients should be aware of this interaction.

Gabapentinoid–opioid co‐prescribing needs urgent revision.

Public health risks associated with methadone in Iran: A systematic review and meta-analysis

BACKGROUND

There has been a marked growth in methadone maintenance treatment (MMT) in Iran in the past two decades with positive health outcomes. We conducted a systematic review of studies on the prevalence of non-prescribed methadone use, methadone use disorder, and methadone-related poisoning and mortality in Iran.

METHODS

We searched International and Iranian databases up to May 2020 and contacted relevant experts. The pooled proportions were estimated through random-effects model. Methadone-related adverse outcomes were evaluated over time.

RESULTS

Sixty-five studies were included. The pooled estimates of non-prescribed methadone use in the last 12-month were 2.7% (95%CI: 0.9-5.4) and 0.1% (95%CI: 0.03-0.2) in the male and female general population, respectively. Among people who use drugs, 8.4% reported daily non-prescribed use in 2018. Four heterogeneous studies in drug treatment centers reported the existence of treatment-seeking for methadone use disorder. Methadone was responsible for 10.4% (95%CI: 4.5-18.3) of cases of acute poisoning in adults and 16.0% (95%CI: 9.3-24.1) in children. Methadone was reported as a cause of death in 53.5% of substance-related deaths referred to the Legal Medicine Organization while being the only cause in 35.8% of all cases.

CONCLUSION

Non-prescribed use of methadone in the general population is much less than opiates and some other available prescription opioids, like tramadol. However, notwithstanding the large and successful MMT program in Iran, increasing trends in methadone-related poisoning and deaths pose serious public health concerns. There is an urgent need to explore these fatal and non-fatal poisoning cases and implement policies to curb the harms associated with methadone use.

Are we repeating mistakes of the past? A review of the evidence for esketamine

Esketamine has been licensed for 'treatment-resistant depression' in the USA, UK and Europe. Licensing trials did not establish efficacy: two trials were negative, one showed a statistically significant but clinically uncertain effect, and a flawed discontinuation trial was included, against Food and Drug Administration precedent. Safety signals - deaths, including suicides, and bladder damage - were minimised.

Absence of drug-drug interactions between γ-hydroxybutyric acid (GHB) and cobicistat

OBJECTIVES

Potential interactions between CYP3A4 inhibitors and γ-hydroxybutyric acid (GHB) have been suggested as a possible explanation for cases of GHB overdose in recent years among people living with HIV engaged in chemsex. Our objective was to assess the effect of cobicistat on the pharmacokinetics of GHB.

METHODS

Fifteen healthy adults were enrolled in this randomized, double-blind, placebo-controlled, two-arm, crossover clinical trial. Participants underwent two 5 day treatment periods with at least a 1 week washout period between them. In each treatment period, participants received cobicistat (150 mg q24h orally) or matched placebo. On day 5 of each treatment period, participants were given a single oral dose of GHB (25 mg/kg). Plasma concentrations of GHB, subjective effects, blood pressure, heart rate and oxygen saturation were monitored for 5 h after dosing. GHB pharmacokinetic and pharmacodynamic parameters were calculated for each participant during each study period by non-compartmental analysis and were compared using linear mixed-effects models. The study was registered at https://www.clinicaltrialsregister.eu (Eudra-CT number 2019-002122-71) and at https://clinicaltrials.gov (NCT04322214).

RESULTS

Ten participants completed the two study periods. No drug-related adverse events that necessitated subject withdrawal or medical intervention occurred during the study. Compared with placebo, none of the primary pharmacokinetic parameters of GHB was substantially changed by the administration of GHB with cobicistat. Similarly, no differences regarding subjective or physiological effects were observed when GHB was administered alone or with cobicistat.

CONCLUSIONS

Neither pharmacokinetic nor pharmacodynamic drug-drug interactions between cobicistat and GHB were identified in this study.

Characteristics of fatal gabapentinoid-related poisoning in Australia, 2000-2020

INTRODUCTION

Gabapentinoids are centrally active GABA agonists whose use has increased substantially in the past decade. The current study aimed to provide a comprehensive clinical profile of a national case series of fatal poisonings related to gabapentinoids.

METHODS

Retrospective study of all deaths due to drug toxicity in Australia in which gabapentinoids were a contributory mechanism, retrieved from the National Coronial Information System (2000-2020). Information was collected on case characteristics, toxicology and major organ pathology.

RESULTS

A total of 887 cases were identified, with a mean age of 45.7 years and 55.2% being male. Death was due to accidental toxicity in 81.3% of cases and intentional in 18.7%. Pre-existing disease was co-contributory to drug toxicity in 19.5%. Pregabalin was present in 92.9% of cases, with a median blood concentration of 7.6 mg/L (range 0.1-850.0 mg/L). Gabapentin was present in 7.2%, with a median blood concentration of 9.5 mg/L (range 0.5-1940.0 mg/L). Both pregabalin and gabapentin were present in five cases. No other gabapentinoids were detected. Drugs other than gabapentinoids were present in 99.8%, most frequently opioids (90.1%), hypnosedatives (76.9%) and antidepressants (60.5%). A body mass index in the obese range was seen in 45.4%. Clinically significant pre-existing disease was common, notably cardiomegaly (24.9%), emphysema (20.2%), nephrosclerosis (18.7%) and severe hepatic steatosis (11.7%).

CONCLUSIONS

The concomitant use of other drugs was close to universal, with CNS depressants predominating. Mental health problems, chronic pain and substance misuse were prominent.

Fatal and non-fatal health incidents related to recreational ecstasy use

BACKGROUND

The recreational drug ecstasy (3,4-methylenedioxymethamphetamine) is currently used world-wide. Severe (including fatal) health incidents related to ecstasy have been reported but a risk assessment of acute non-fatal and fatal ecstasy-related health incidents has never been performed.

METHODS

In the current risk assessment review, national data of non-fatal health incidents collected in the Netherlands were combined with the nationwide exposure to ecstasy, that is, last-year prevalence of ecstasy use. In addition, the annual number of ecstasy-related deaths in Great Britain (Scotland, Wales and England) was used to assess the risk of fatal ecstasy-related cases.

RESULTS

In the Netherlands, the estimated risk of a moderate to severe acute health incident following the use of ecstasy is one in 900 pills (0.11%), whereas for cocaine it is one in 1600 doses (0.06%) and for gamma-hydroxybutyrate one in 95 doses (1.05%). With respect to ecstasy-related deaths in Great Britain, the estimated risk of ecstasy alone per user is 0.01-0.06%, which is close to the range of the fatality risk in chronic alcohol users (0.01-0.02%), amphetamine users (0.005%) and cocaine users (0.05%), but much lower than that of opiate use (heroin and morphine: 0.35%).

CONCLUSION

The current review shows that almost no data are available on the health risks of ecstasy use. The few data that are available show that ecstasy is not a safe substance. However, compared to opiates (heroin, morphine), the risk of acute ecstasy-related adverse health incidents per ecstasy user and per ecstasy use session is relatively low.

Recent trends in heroin and pharmaceutical opioid-related harms in Victoria, Australia up to 2018

AIMS

To characterize the trajectory in the years leading up to 2018 in pharmaceutical opioid and heroin morbidity in Victoria, Australia, and to assess the effect on that trajectory of reformulation of oxycodone to a form that could not be easily snorted or injected.

DESIGN

Interrupted time-series analyses of population-level data before versus after reformulation of oxycodone, stratified by sex.

SETTING

Victoria, Australia.

PARTICIPANTS

The population of Victoria aged 12+ years.

MEASUREMENTS

Ambulance patient care and emergency department (ED) records were examined using both fixed-code and free-text fields, with each record manually cleaned and checked by trained coders. These were used to derive the output variables providing an index of harm: rates of opioid-related ambulance attendances and ED attendances for pharmaceutical opioids and heroin. The input variable was pre- versus post-oxycodone reformulation.

FINDINGS

There were 30 045 opioid-related ambulance attendances from January 2012 to October 2018 (54% heroin-related), and 10 113 ED attendances from July 2008 to June 2018 (39% heroin-related). There was an increase in the rate (events per 100 000 people per year) of all opioid ED attendances from 2008 to 2018 [increase = 0.063; 95% confidence interval (CI) = 0.049, 0.078]. Pharmaceutical opioid ED attendances decreased from 2014 onwards (slope change = -0.083; 95% CI = -0.108, -0.059). Heroin-related ED attendances increased from 2014 to 2018; 11 324 heroin-related ambulance attendances and 1980 ED attendances were observed from April 2014 to June 2018, compared with the respective estimates of 8176, and 1661 had the pre-April 2014 trend continued (ambulance slope change = 0.296, 95% CI = 0.104, 0.489; ED slope change = 0.026, 95% CI = 0.005, 0.046). The inflection point of 2014 coincided with the re-formulation of oxycodone.

CONCLUSION

In Victoria, Australia, there appears to have been a trend starting around mid-2014 of increasing heroin-related harm, and a flattening of the increase or a decrease of harms relating to pharmaceutical opioids. These changes may, in part, reflect reformulation of oxycodone to reduce the extent to which it can be injected or snorted.

Using the pharmacy retail model to examine perceptions and biases of a UK population sample towards regulation of specific psychoactive drugs

Background:

Contemporary research indicates that the legal classifications of cannabis (Schedule 2, Class B), 3,4-methylenedioxymethamphetamine (MDMA) (Schedule 1, Class A) and psilocybin (Schedule 1, Class A) in the United Kingdom are not entirely based on considerations of harm and therapeutic utility. The legal classifications of the substances discussed are typically determined by legislators such as Parliament and, therefore, may be a reflection of the views or perceived views of the general public.

Objective:

The aim of the study was to provide an indication of the underlying psychology regarding the legislated sale of alcohol, tobacco, cannabis, MDMA and psilocybin in pharmacies according to a UK general population sample.

Methods:

A sample of 105 UK nationals was selected for the survey. Participants were asked questions on perceived relative harm of the five substances. After viewing contemporary information on reported relative harm and therapeutic applications, the participants were asked questions related to using the pharmacy retail model for the sale of the substances discussed. Participants who opposed the substances being sold primarily in pharmacies were asked to explain their rationale according to a predetermined list of options for each of the five drugs. Participants were also asked whether they consider it a human right to be legally permitted to consume the substances.

Results:

The participants' perceptions of relative harm (tobacco > MDMA > psilocybin > alcohol > cannabis) were not in agreement with the relative harm reported in the literature (alcohol > tobacco > cannabis > MDMA > psilocybin). Principal objections to the currently illicit substances being legally available in pharmacies include it sending the wrong message; it feels wrong; it is too dangerous; disliking the smell of cannabis; disapproval of the people; and not liking the idea of people using psychoactive drugs for entertainment or to have mystical/religious experiences. Overall, the participants determined that being legally permitted to consume the substances discussed is an issue of relevance to human rights. A majority of the male participants concluded that being legally permitted to consume alcohol, tobacco, cannabis and Psilocybe mushrooms is a human right in contrast to the majority of female participants who solely considered alcohol consumption to be a human right.

Conclusions:

The data suggest that the legal classifications may not simply be based on considerations of harm. Misperceptions of the dangers, biases and non-health-related aversions likely contribute to the continuation of policies that do not reflect the state of scientific research.

Detection of fentanyl and fentanyl analogues in biological samples using liquid chromatography-high resolution mass spectrometry

BACKGROUND

Fentanyl and analogues such as butyrylfentanyl, carfentanil, 4-fluorobutyrylfentanyl, and furanylfentanyl may be either added to, or sold as, heroin. Fentanyl and carfentanil have approximately 100 and 10,000 times the potency of morphine, respectively, and there is thus a high risk of death with the use of these drugs.

METHODS

We looked for fentanyl/fentanyl analogues using liquid chromatography-high resolution mass spectrometry (LC-HRMS) in selected biological samples obtained post-mortem February 2017-end January 2018. Suspicion of fentanyl poisoning arose from the circumstances of death, a history of heroin use, and the geographical area in which the deceased was discovered, supplemented by drugs intelligence data.

RESULTS

Of the 84 deaths investigated, fentanyl and/or a fentanyl analogue were detected in 40 (48%). The fentanyls encountered were carfentanil (N = 17), fentanyl (9), carfentanil and fentanyl together (12), and fentanyl, carfentanil, 4-fluorobutyrylfentanyl, and butyrylfentanyl together (2). The median (range) post-mortem blood fentanyl concentration was 2.66 (0.21-107) μg/L and the median (range) carfentanil concentration was 0.24 (0.03-1.66) μg/L. The most prevalent compounds present together with fentanyls were ethanol [N = 28, median (range) post-mortem blood concentration: 44 (<10-249) mg/dL)], benzoylecgonine [N = 22, 0.64 (<0.05-3.17) mg/L] and free morphine [N = 20, 0.05 (<0.05-0.34) mg/L]. Deaths in hospital excluded, median blood free morphine, and ethanol concentrations were significantly lower in deaths where fentanyl/fentanyl analogues were present, but there was much overlap with the blood concentrations of these analytes in the non-fentanyl related deaths. A routine drugs of abuse assay using LC-HRMS identified fentanyl with 100% sensitivity and carfentanil with 89% sensitivity.

CONCLUSIONS

Given their potency, misuse of fentanyl and its analogues is likely to cause severe toxicity. A simple LC-HRMS method detected all cases in which fentanyl was identified post-mortem and most of the cases in which carfentanil was detected.