Impact of a transient instability of the ecstasy market on health concerns and drug use patterns in The Netherlands

Drug checking services for people who use drugs: a systematic review

BACKGROUND AND AIMS

Drug checking services provide people who use drugs with chemical analysis results of their drug samples while simultaneously monitoring the unregulated drug market. We sought to identify and synthesize literature on the following domains: (a) the influence of drug checking services on the behaviour of people who use drugs; (b) monitoring of drug markets by drug checking services; and (c) outcomes related to models of drug checking services.

METHODS

Systematic review. A systematic literature search was conducted in MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, PsycINFO, Scopus, Web of Science and Dissertations and Theses Global. Eligible studies were peer-reviewed articles and conference abstracts or grey literature, published in any language since 1990 and including original data on the domains. We assessed risk of bias for quantitative peer-reviewed articles reporting on behaviour or models of drug checking services using National Institutes of Health tools.

RESULTS

We screened 2463 titles and abstracts and 156 full texts, with 90 studies meeting inclusion criteria. Most (n = 65, 72.2%) were from Europe and used cross-sectional designs (n = 79, 87.7%). Monitoring of drug markets by drug checking services (n = 63, 70%) was the most reported domain, followed by the influence of drug checking services on behaviour (n = 31, 34.4%), including intent to use, actual use and disposal of the drug, and outcomes related to models of drug checking services (n = 17, 18.9%). The most common outcome measures were detection of unexpected substances (n = 50, 55.6%), expected substances (n = 44, 48.9%), new psychoactive substances (n = 40, 44.4%) and drugs of concern (n = 32, 36.5%) by drug checking services.

CONCLUSIONS

Drug checking services appear to influence behavioural intentions and the behaviour of people who use drugs, particularly when results from drug checking services are unexpected or drugs of concern. Monitoring of drug markets by drug checking services is well established in Europe, and increasingly in North America. Concerns about drug contents and negative health consequences facilitate the use of drug checking services; lack of concern; trust in drug sellers; lack of accessibility of drug checking services; and legal and privacy concerns are barriers to use.

Prevalence of reagent test-kit use and perceptions of purity among ecstasy users in an electronic dance music scene in New York City

INTRODUCTION AND AIMS

Ecstasy users in the electronic dance music scene are at high risk for using ecstasy adulterated with new psychoactive substances and/or methamphetamine. We examined self-reported testing of ecstasy among users in this scene.

DESIGN AND METHODS

We surveyed individuals (aged 18-40 years) entering electronic dance music parties in New York City in 2017. Past-year ecstasy users (n = 351) were asked if they had tested their ecstasy in the past year. We estimated prevalence and correlates of having tested one's ecstasy.

RESULTS

23.1% reported having tested their ecstasy in the past year. Those with some college (adjusted prevalence ratio [aPR] = 0.49, P = 0.014) or a college degree (aPR = 0.41, P = 0.025) were less likely to test their ecstasy than those with a high school diploma or less. Using ecstasy pills (aPR = 1.89, P = 0.036) or crystals (aPR = 1.90, P = 0.006) ≥3 times in the past year was associated with increased likelihood of testing one's ecstasy, and purchasing from an unknown or untrustworthy dealer was associated with decreased likelihood (aPR = 0.63, P = 0.034) of testing one's ecstasy. Half (51.1%) of ecstasy users reported finding out or suspecting their ecstasy had contained a drug other than MDMA. Of these, 49.2% reported finding out their ecstasy contained methamphetamine or speed/amphetamine. Most ecstasy users reported that they would be less likely to use again upon learning their ecstasy contained 'bath salts' (54.8%) or methamphetamine (54.3%).

DISCUSSION AND CONCLUSIONS

Drug testing appears to help ecstasy users detect adulterants and results can help inform harm reduction efforts. Less frequent users in particular may require education about adulteration and drug-testing.

Escalation of intravenous self-administration of methylone and mephedrone under extended access conditions

The recreational use of substituted cathinones continues to grow as a public health concern in the United States. Studies have shown that extended access to intravenous (i.v.) self-administration of stimulants, such as cocaine and methamphetamine, results in escalation of drug intake relative to shorter access; however, little is known about the impact of extended access on self-administration of entactogen class stimulants such as methylone and 4-methylmethcathinone (mephedrone). Male Wistar rats were randomly assigned to short-access (ShA, 2- h) and long-access (LgA, 6- h) groups and trained to self-administer methylone or mephedrone (0.5 mg/kg/infusion) using a fixed-ratio 1 response contingency. The methylone-trained groups were evaluated on a progressive-ratio (PR) procedure incorporating dose-substitution of methylone (0.125-2.5 mg/kg/infusion), mephedrone (0.125-2.5 mg/kg/infusion) or methamphetamine (MA; 0.01-0.5 mg/kg/infusion). Mephedrone-trained rats were similarly evaluated on a PR with mephedrone and MA. Rats trained with LgA to methylone and mephedrone earned more infusions during acquisition compared with ShA groups. Mephedrone-trained LgA rats reached significantly higher breakpoints than all other groups in mephedrone and MA PR tests. Methylone-trained LgA rats exhibited a rightward shift of the peak effective dose but no overall efficacy change compared with methylone-trained ShA rats. These findings show that the self-administration of mephedrone escalates under LgA conditions in a manner similar to traditional stimulants whereas escalation of 6 h intakes of methylone is not accompanied by differences in PR performance. Thus mephedrone represents the greater risk for dysregulated drug consumption.

Atypical binding at dopamine and serotonin transporters contribute to the discriminative stimulus effects of mephedrone

Mephedrone (4-methylmethcathinone), a constituent of the recreational substances known as "bath salts", is a synthetic cathinone that can produce auditory and visual hallucinations, as well as problematic cardiovascular effects. This study compared the discriminative stimulus effects of mephedrone (0.32-10 mg/kg) with other prototypical drugs of abuse: cocaine (0.56-32 mg/kg), d-amphetamine (0.18-3.2 mg/kg), ketamine (1.8-18 mg/kg), phencyclidine (PCP, 1-5.6 mg/kg), heroin (1-10 mg/kg), 2,5-dimethoxy-4-iodoamphetamine (R-DOI, 0.1-1 mg/kg), Δ⁹-tetrahydrocannabinol (Δ^9-THC 0.56-5.6 mg/kg), 3,4-methylenedioxyamphetamine (MDA, 0.32-5.6 mg/kg), methylphenidate (1-10 mg/kg), and 3,4-methylenedioxypyrovalerone (MDPV, 0.56-5.6 mg/kg). The discriminative stimulus effects of mephedrone were also assessed after administration of the sigma receptor antagonist rimcazole (0.32-10 mg/kg), the relatively selective norepinephrine transporter (NET) inhibitor desipramine (1.8-18 mg/kg), and the selective serotonin transporter (SERT) inhibitor fluoxetine (1-18 mg/kg). Initially, rats were trained to discriminate an intraperitoneal injection of mephedrone (3.2 mg/kg) from saline under a fixed-ratio 20 schedule of food presentation. Following training, cumulative doses of mephedrone and the other drugs were administered to test for substitution (80% drug-lever responding). Of the drugs tested, including those that were tested in combination with mephedrone (i.e., rimcazole, desipramine, and fluoxetine), only cocaine fully substituted for mephedrone without substantially decreasing response rate. In addition, the three drugs administered in combination with mephedrone shifted the cumulative dose-effect curves leftward (percent drug-lever responding) and down (response rate), although fluoxetine did so in a dose-dependent manner ranging from antagonism to potentiation. In summary, the discriminative stimulus effects of mephedrone were most similar to those for the central nervous system (CNS) stimulant, cocaine, and SERT and DAT activity were necessary for these effects.

Predicting the Abuse Liability of Entactogen-Class, New and Emerging Psychoactive Substances via Preclinical Models of Drug Self-administration

Animal models of drug self-administration are currently the gold standard for making predictions regarding the relative likelihood that a recreational drug substance will lead to continued use and addiction. Such models have been found to have high predictive accuracy and discriminative validity for a number of drug classes including ethanol, nicotine, opioids, and psychostimulants such as cocaine and methamphetamine. Members of the entactogen class of psychostimulants (drugs that produce an "open mind state" including feelings of interpersonal closeness, intimacy and empathy) have been less frequently studied in self-administration models. The prototypical entactogen 3,4-methylenedioxymethamphetamine (MDMA; "Ecstasy") supports self-administration but not with the same consistency nor with the same efficacy as structurally related drugs amphetamine or methamphetamine. Consistent with these observations, MDMA use is more episodic in the majority of those who use it frequently. Nevertheless, substantial numbers of MDMA users will meet the criteria for substance dependence at some point in their use history. This review examines the currently available evidence from rodent self-administration studies of MDMA and two of the new and emerging psychoactive substances (NPS) that produce entactogen type neuropharmacological responses - mephedrone (4-methylmethcathinone; 4MMC; "meow meow") and methylone (3,4-methylenedioxymethcathinone). Overall, the current evidence predicts that these NPS entactogens have enhanced abuse liability compared with MDMA.

Verbal Memory Impairment in Polydrug Ecstasy Users: A Clinical Perspective

BACKGROUND

Ecstasy use has been associated with short-term and long-term memory deficits on a standard Word Learning Task (WLT). The clinical relevance of this has been debated and is currently unknown. The present study aimed at evaluating the clinical relevance of verbal memory impairment in Ecstasy users. To that end, clinical memory impairment was defined as decrement in memory performance that exceeded the cut-off value of 1.5 times the standard deviation of the average score in the healthy control sample. The primary question was whether being an Ecstasy user (E-user) was predictive of having clinically deficient memory performance compared to a healthy control group.

METHODS

WLT data were pooled from four experimental MDMA studies that compared memory performance during placebo and MDMA intoxication. Control data were taken from healthy volunteers with no drug use history who completed the WLT as part of a placebo-controlled clinical trial. This resulted in a sample size of 65 E-users and 65 age- and gender-matched healthy drug-naïve controls. All participants were recruited by similar means and were tested at the same testing facilities using identical standard operating procedures. Data were analyzed using linear mixed-effects models, Bayes factor, and logistic regressions.

RESULTS

Findings were that verbal memory performance of placebo-treated E-users did not differ from that of controls, and there was substantial evidence in favor of the null hypothesis. History of use was not predictive of memory impairment. During MDMA intoxication of E-users, verbal memory was impaired.

CONCLUSION

The combination of the acute and long-term findings demonstrates that, while clinically relevant memory impairment is present during intoxication, it is absent during abstinence. This suggests that use of Ecstasy/MDMA does not lead to clinically deficient memory performance in the long term. Additionally, it has to be investigated whether the current findings apply to more complex cognitive measures in diverse 'user categories' using a combination of genetics, imaging techniques and neuropsychological assessments.

Young adults' trajectories of Ecstasy use: a population based study

Young adults' Ecstasy use trajectories have important implications for individual and population-level consequences of Ecstasy use, but little relevant research has been conducted. This study prospectively examines Ecstasy trajectories in a population-based sample. Data are from the Natural History Study of Drug Use, a retrospective/prospective cohort study conducted in Australia. Population screening identified a probability sample of Ecstasy users aged 19-23 years. Complete data for 30 months of follow-up, comprising 4 time intervals, were available for 297 participants (88.4% of sample). Trajectories were derived using cluster analysis based on recent Ecstasy use at each interval. Trajectory predictors were examined using a generalized ordered logit model and included Ecstasy dependence (World Mental Health Composite International Diagnostic Instrument), psychological distress (Hospital Anxiety Depression Scale), aggression (Young Adult Self Report) and contextual factors (e.g. attendance at electronic/dance music events). Three Ecstasy trajectories were identified (low, intermediate and high use). At its peak, the high-use trajectory involved 1-2 days Ecstasy use per week. Decreasing frequency of use was observed for intermediate and high-use trajectories from 12 months, independently of market factors. Intermediate and high-use trajectory membership was predicted by past Ecstasy consumption (>70 pills) and attendance at electronic/dance music events. High-use trajectory members were unlikely to have used Ecstasy for more than 3 years and tended to report consistently positive subjective effects at baseline. Given the social context and temporal course of Ecstasy use, Ecstasy trajectories might be better understood in terms of instrumental rather than addictive drug use patterns.

Mexico's precursor chemical controls: emergence of less potent types of methamphetamine in the United States

BACKGROUND

This study examines whether Mexico's controls on ephedrine and pseudoephedrine, the two precursor chemicals that yield the most potent form of methamphetamine, d-methamphetamine, impacted the prevalence/availability of less potent types of methamphetamine in the United States-types associated with the alternative precursor chemical P2P.

METHOD

Using ARIMA-intervention time series analysis of monthly drug exhibits (a prevalence/availability indicator) from the System to Retrieve Information from Drug Evidence (STRIDE), we tested whether Mexico's controls, which began in 2005, were associated with growth/decline in d-methamphetamine and growth/decline in P2P-associated, less potent l-methamphetamine, racemic methamphetamine (a 50:50 ratio of d- and l-isomers), and mixed isomer methamphetamine (an unequal ratio of d- and l-isomers). Heroin, cocaine and marijuana exhibits were used for quasi-control (01/2000-04/2011).

RESULTS

Mixed-isomer exhibits constituted about 4% of the methamphetamine exhibits before Mexico's controls, then rose sharply in association with them and remained elevated, constituting about 37% of methamphetamine exhibits in 2010. d-Methamphetamine exhibits dropped sharply; l-methamphetamine and racemic methamphetamine exhibits had small rises. d-Methamphetamine exhibits partially recovered in the US West, but little recovery occurred in the US Central/South. Quasi-control series were generally unaffected.

CONCLUSION

The US methamphetamine market changed. Widespread emergence of less potent methamphetamine occurred in conjunction with Mexico's controls. And prevalence/availability of the most potent type of the drug, d-methamphetamine, declined, a partial recovery in the West notwithstanding. Granting that lower potency drugs typically engender less dependence and attendant problems, these findings suggest that, following Mexico's controls, the potential harm of a sizeable amount of the US methamphetamine supply decreased.

Do novel psychoactive substances displace established club drugs, supplement them or act as drugs of initiation? The relationship between mephedrone, ecstasy and cocaine

BACKGROUND/AIMS

To assess whether novel psychoactive substances (NPS) displace established club drugs, supplement them or act as drugs of initiation via a study of the relationship between mephedrone, ecstasy pills, cocaine and MDMA powder amongst club-goers considered to be 'early adopters' of psychostimulant/club drug trends.

METHODS

In situ surveys were conducted with 308 customers in two south London gay dance clubs across 3 weekend nights in July 2010 to assess the prevalence and patterns of self-reported use of a range of illegal drugs and NPS.

RESULTS

Mephedrone was added to existing drug repertoires amongst those surveyed and acted to supplement more established club drugs including ecstasy pills, cocaine and MDMA powder, rather than replacing or displacing those drugs.

CONCLUSION

This survey suggests that NPS are likely to be added to drug repertoires, particularly amongst experienced users with consequent health risks for individuals and resource implications for services. This study points to a complex relationship between NPS and illegal drug availability, purity and regulatory control, one which is increasingly important to understand given the global emergence of NPS and the challenges they present to existing supply, demand and harm reduction strategies.