Acute toxicity following analytically confirmed use of the novel psychoactive substance (NPS) methiopropamine. A report from the Identification of Novel psychoActive substances (IONA) study

Understanding methiopropamine, a new psychoactive substance: an in-depth review on its chemistry, pharmacology and implications to human health

Methiopropamine or 1-(thiophen-2-yl)-2-methylaminopropane (MPA) is a thiophene ring-based structural analogue of methamphetamine, first synthesized in 1942 but become popular when it started to be available for purchase on websites selling 'legal highs' since 2010. While it is legally controlled in many countries, it remains readily accessible and frequently encountered in recreational settings. The growing prevalence of MPA use results in new therapeutic challenges. Relatively few studies have focused on its pharmacodynamics and pharmacokinetics, making it important to better understand its potential risks and harmful effects in humans in terms of its toxicity. This review provides a comprehensive profiling of MPA toxicological properties, including its chemical properties, analytical methods, prevalence, patterns of use, and legal status. Additionally, it discusses the drug's effects on the central nervous system, its potential for addiction, and its adverse physical and mental health effects. Improving the understanding of safety aspects of MPA and how it imposes health threats for public health will guide the development of therapeutic approach of its intoxication and guide the authorities in deciding its legal status.

A risk-based approach to community illicit drug toxicosurveillance: operationalisation of the Emerging Drugs Network of Australia - Victoria (EDNAV) project

INTRODUCTION

The Emerging Drugs Network of Australia - Victoria (EDNAV) project is a newly established toxicosurveillance network that collates clinical and toxicological data from patients presenting to emergency departments with illicit drug related toxicity in a centralised clinical registry. Data are obtained from a network of sixteen public hospital emergency departments across Victoria, Australia (13 metropolitan and three regional). Comprehensive toxicological analysis of a purposive sample of 22 patients is conducted each week, with reporting of results to key alcohol and other drug stakeholders. This paper describes the overarching framework and risk-based approach developed within Victoria to assess drug intelligence from EDNAV toxicosurveillance.

METHODS

Risk management principles from other spheres of public health surveillance and healthcare clinical governance have been adapted to the EDNAV framework with the aim of facilitating a consistent and evidence-based approach to assessing weekly drug intelligence. The EDNAV Risk Register was reviewed over the first two years of EDNAV project operation (September 2020 - August 2022), with examples of eight risk assessments detailed to demonstrate the process from signal detection to public health intervention.

RESULTS

A total of 1112 patient presentations were documented in the EDNAV Clinical Registry, with 95 signals of concern entered into the EDNAV Risk Register over the two-year study period. The eight examples examined in further detail included suspected drug adulteration (novel opioid adulterated heroin, para-methoxymethamphetamine adulterated 3,4-methylenedioxymethamphetamine (MDMA)), drug substitution (25B-NBOH sold as lysergic acid diethylamide, five benzodiazepine-type new psychoactive substances in a single tablet, protonitazene sold as ketamine), new drug detection (N,N-dimethylpentylone), contamination (unreported acetylfentanyl) and a fatality subsequent to MDMA use. A total of four public Drug Alerts were issued over this period.

CONCLUSIONS

Continued toxicosurveillance efforts are paramount to characterising the changing landscape of illicit drug use. This work demonstrates a functional model for risk assessment of illicit drug toxicosurveillance, underpinned by analytical confirmation and evidence-based decision-making.

New Psychoactive Substances: Major Groups, Laboratory Testing Challenges, Public Health Concerns, and Community-Based Solutions

Across communities worldwide, various new psychoactive substances (NPSs) continue to emerge, which worsens the challenges to global mental health, drug rules, and public health risks, as well as combats their usage. Specifically, the vast number of NPSs that are currently available, coupled with the rate at which new ones emerge worldwide, increasingly challenges both forensic and clinical testing strategies. The well-established NPS detection techniques include immunoassays, colorimetric tests, mass spectrometric techniques, chromatographic techniques, and hyphenated types. Nonetheless, mitigating drug abuse and NPS usage is achievable through extensive community-based initiatives, with increased focus on harm reduction. Clinically validated and reliable testing of NPS from human samples, along with community-driven solution, such as harm reduction, will be of great importance, especially in combating their prevalence and the use of other illicit synthetic substances. There is a need for continued literature synthesis to reiterate the importance of NPS, given the continuous emergence of illicit substances in the recent years. All these are discussed in this overview, as we performed another look into NPS, from differentiating the major groups and identifying with laboratory testing challenges to community-based initiatives.

Novel psychoactive substances-related presentations to the emergency departments of the European drug emergencies network plus (Euro-DEN plus) over the six-year period 2014-2019

INTRODUCTION

Novel psychoactive substances (NPS) have been increasingly reported in the last 15-20 years. We aimed to describe presentations to the emergency department (ED) with acute recreational drug toxicity involving NPS.

METHODS

Data were extracted from the European Drug Emergencies Network (Euro-DEN) Plus database for all presentations to ED (36 EDs in 24 European countries) with acute toxicity between January 2014 and December 2019. Patient demographics, agents involved, and clinical outcomes were described and the subgroup of presentations involving NPS was compared with the rest of the cohort.

RESULTS

Out of 43,633 Euro-DEN Plus presentations, 3304 (7.6%) involved at least one NPS. Agents were identified mainly based on self-report or clinical presentation, with analytical confirmation being performed only in 17.9% of NPS presentations. The proportion of NPS presentations varied by centre (0-48.8%). For centres where data were available for all 6 years, NPS-related presentations peaked in 2015 (11.9%). In 2014, 78.4% of NPS agents reported were cathinones, while only 3.4% were synthetic cannabinoids (SCs); conversely, in 2019 only 11.6% of NPS agents reported were cathinones, while 72.2% were SCs. NPS-related presentations involved younger patients (median 30 (23-37) vs. 32 (25-40) years, p < 0.001) and more males (84.8 vs. 75.8%, p < 0.001) compared with the rest of the cohort. Patients presenting to ED after using NPS were more likely to self-discharge (22.8 vs. 15.1%), less likely to be admitted to critical care (3.6 vs. 6.1%) but had a longer length of stay in hospital (median 5.1 (2.7-18.7) vs. 4.7 (2.5-9.2) h, p < 0.001). Death occurred in 0.5% of all presentations involving NPS and in 0.4% of non-NPS presentations.

CONCLUSIONS

This large multicentre series of NPS presentations to European EDs showed marked geographical variation and changes over time in the proportion of presentations to ED involving NPS, as well as the proportion of NPS subgroups.

Trends in hospital presentations following analytically confirmed synthetic cannabinoid receptor agonist exposure before and after implementation of the 2016 UK Psychoactive Substances Act

BACKGROUND AND AIMS

The United Kingdom (UK) Psychoactive Substances Act (PSA), implemented on the 26^th  May 2016, made the production, supply and sale of all non-exempted psychoactive substances illegal. The aim of this study was to measure trends in hospital presentations for severe toxicity following analytically confirmed synthetic cannabinoid receptor agonist (SCRA) exposure before and after implementation of the PSA.

DESIGN

Observational study.

SETTING

Thirty-four hospitals across the UK participating in the Identification of Novel Psychoactive Substances (IONA) study.

PARTICIPANTS

A total of 627 (79.9% male) consenting individuals who presented to participating hospitals between July 2015 and December 2019 with severe acute toxicity and suspected novel psychoactive substances exposure.

MEASUREMENTS

Toxicological analyses of patient samples were conducted using liquid-chromatography tandem mass-spectrometry. Time-series analysis was conducted on the monthly number of patients with and without analytically confirmed SCRA exposure using Poisson segmented regression.

FINDINGS

SCRAs were detected in 35.7% (n = 224) of patients. After adjusting for seasonality and the number of active sites, models showed no clear evidence of an upward or downward trend in the number of SCRA exposure cases in the period before (incidence rate ratio [IRR], 1.12; 95% CI, 0.99-1.26; P = 0.068) or after (IRR, 0.97; 95% CI, 0.94-1.01; P = 0.202) the implementation of the PSA. There was also no clear evidence of an upward or downward trend in non-SCRA exposure cases before (IRR, 1.12; 95% CI, 0.98-1.27; P = 0.105) or after (IRR, 1.01; 95% CI, 0.98-1.04; P = 0.478) implementation of the PSA.

CONCLUSIONS

There is no clear evidence of an upward or downward trend in the number of patients presenting to UK hospitals with severe acute toxicity following analytically confirmed synthetic cannabinoid receptor agonist exposure since the implementation of the Psychoactive Substances Act.

The Emerging Drugs Network of Australia: A toxicosurveillance system of illicit and emerging drugs in the emergency department

OBJECTIVE

The unprecedented rise in synthetic drugs, many containing unknown toxic agents, has made timely analytical diagnosis more difficult, and has reduced the confidence of clinicians providing ED management to this population of patients. This has also impacted the quality of evidence informing harm reduction responses. The Emerging Drugs Network of Australia (EDNA) brings together emergency physicians, toxicologists and forensic laboratories to establish a standardised ED toxicosurveillance system in Australia.

METHODS

Blood analysis of intoxicated patients will be conducted by forensic laboratories to enable precise identification of the substances causing acute toxicity. This will be linked with clinical data collected at the time of ED presentation to enable analysis of the clinical effects and outcomes associated with different illicit and emerging drugs. Toxicological and clinical data collected across sentinel sites will align with a nationally endorsed minimum dataset.

RESULTS

EDNA's collaborative network will establish a national system of surveillance and reporting of illicit and emerging drugs causing acute toxicity. Standardisation of data collection recorded in a national clinical registry will provide more robust data on epidemiology and associated harms. This will facilitate the translation of clinical and toxicological evidence into timely, appropriate harm reduction and policy.

CONCLUSION

Our work represents a collaborative response to calls for more sophisticated data on emerging drug trends in Australia. EDNA will improve coordination between clinicians and analytical services by way of its standardised approach to surveillance and reporting.

Low-normal doses of methiopropamine induce aggressive behaviour in mice

Recreational use of illicit methiopropamine (MPA) is a public health concern because it produces neurochemical effects comparable with those induced by methamphetamine (METH). The present study investigated the effects of MPA on the expression of an aggressive behaviour. Eighty CD-1 male mice, after receiving intraperitoneal injection of saline, MPA (0.01-10 mg/kg), METH (0.01-10 mg/kg), or AMPH (0.01-10 mg/kg), once a week over a 5-week period, underwent the resident-intruder test and spontaneous locomotor activity measurement. Results showed that all psychostimulants induce aggressive behaviour even at low doses, with a dose-dependent increase and a time-dependent sensitisation. MPA potency was similar to METH and superior to AMPH. Therefore, MPA-induced aggressive behaviour may appear even at MPA dosages free of cardiovascular or other behavioural adverse effects and could become a non-intentional side effect that users experience after increasing and repeating MPA consumption.

Designer drugs: mechanism of action and adverse effects

Psychoactive substances with chemical structures or pharmacological profiles that are similar to traditional drugs of abuse continue to emerge on the recreational drug market. Internet vendors may at least temporarily sell these so-called designer drugs without adhering to legal statutes or facing legal consequences. Overall, the mechanism of action and adverse effects of designer drugs are similar to traditional drugs of abuse. Stimulants, such as amphetamines and cathinones, primarily interact with monoamine transporters and mostly induce sympathomimetic adverse effects. Agonism at μ-opioid receptors and γ-aminobutyric acid-A (GABAA) or GABAB receptors mediates the pharmacological effects of sedatives, which may induce cardiorespiratory depression. Dissociative designer drugs primarily act as N-methyl-D-aspartate receptor antagonists and pose similar health risks as the medically approved dissociative anesthetic ketamine. The cannabinoid type 1 (CB1) receptor is thought to drive the psychoactive effects of synthetic cannabinoids, which are associated with a less desirable effect profile and more severe adverse effects compared with cannabis. Serotonergic 5-hydroxytryptamine-2A (5-HT2A) receptors mediate alterations of perception and cognition that are induced by serotonergic psychedelics. Because of their novelty, designer drugs may remain undetected by routine drug screening, thus hampering evaluations of adverse effects. Intoxication reports suggest that several designer drugs are used concurrently, posing a high risk for severe adverse effects and even death.