Designer Benzodiazepines: Another Class of New Psychoactive Substances

A computationally supported designer benzodiazepine strategy for public toxicology laboratories

Public laboratories must balance innovative and existing methods to keep up with designer drug trends. This article presents a strategy for handling designer benzodiazepines (DBZDs) in casework from screening to interpretation. The cross-reactivity of 22 DBZDs and metabolites was tested against the Immunalysis™ benzodiazepine (BZD) direct enzyme-linked immunosorbent assay kit. The kit had high intra-analyte precision (coefficients of variation <15%). Inter-analyte performance varied, triggering confirmation testing at concentrations ranging from 35 to 460 μg/L. The Cuyahoga County Regional Forensic Science Laboratory implemented a 40-analyte BZD and Z-drug confirmation method in 2019. Ten additional analytes were later validated for qualitative reporting, and the limits of detection for 13 analytes were lowered by 60%. The method of standard addition was also optimized for as-needed quantitation. Equal and 1/x weighting factors correlated well with target concentrations (coefficients of determination (r2) > 0.98), but 1/x weighting provided the most consistently accurate concentrations. Six computational models were developed to predict γ-aminobutyric acid-A receptor binding affinity to assist in case interpretation (r2 > 0.70 for cross-validation and test set prediction). These models were used to predict the binding affinity of analytes in the confirmation method. Other public laboratories can use this same practical strategy to adapt to any designer drug class (e.g., BZDs, opioids, cannabinoids and stimulants).

Metabolism and detection of designer benzodiazepines: a systematic review

Synthesis and illicit use of designer benzodiazepines are growing concerns, with these new psychoactive substances (NPS) posing serious health consequences and new hurdles for toxicologists. Consumption marker identification and characterization is paramount in confirming their use. The benzodiazepine core structure is a fusion of benzene and a seven-membered heterocycle with two nitrogen atoms forming the diazepine ring. Minor variations on the core structure produce different classes of benzodiazepines with marked differences in physiological effects. The present review provides a comprehensive designer benzodiazepines metabolism overview and suggests suitable human consumption biomarkers for toxicology casework. A systematic literature search of PubMed®, ScopusTM, Web of ScienceTM, and Cochrane databases was conducted independently by two coauthors adhering to PRISMA guidelines. Data from 30 in vitro and in vivo models of designer benzodiazepines metabolism from January 2007 to February 2023 were included. 1,4-benzodiazepines (n = 10), 2,3-benzodiazepines (n = 1), triazolo-benzodiazepines (n = 9), and thieno-triazolo-benzodiazepines (n = 3) study design, sample pretreatment, analytical techniques, and major metabolites detected in various matrices are addressed. Metabolites following hydroxylation and phase II glucuronide conjugation were the most prevalent analytes. N-Glucuronidation of parent azole-fused benzodiazepines, and nitro-reduced and N-acetylated metabolites of nitro-containing designer benzodiazepines were also common. From these data, we propose a generic metabolic pathway for designer benzodiazepines. The sporadic illicit market presents challenges in toxicological casework and necessitates comprehensive biomarker investigations, especially in cases with legal implications. There are few metabolism data for many designer benzodiazepines, emphasizing the need for research focusing on closing these gaps.

Molecular Aspects of the Interactions between Selected Benzodiazepines and Common Adulterants/Diluents: Forensic Application of Theoretical Chemistry Methods

Benzodiazepines are frequently encountered in crime scenes, often mixed with adulterants and diluents, complicating their analysis. This study investigates the interactions between two benzodiazepines, lorazepam (LOR) and alprazolam (ALP), with common adulterants/diluents (paracetamol, caffeine, glucose, and lactose) using infrared (IR) spectroscopy and quantum chemical methods. The crystallographic structures of LOR and ALP were optimized using several functionals (B3LYP, B3LYP-D3BJ, B3PW91, CAM-B3LYP, M05-2X, and M06-2X) combined with the 6-311++G(d,p) basis set. M05-2X was the most accurate when comparing experimental and theoretical bond lengths and angles. Vibrational and 13C NMR spectra were calculated to validate the functional's applicability. The differences between LOR's experimental and theoretical IR spectra were attributed to intramolecular interactions between LOR monomers, examined through density functional theory (DFT) optimization and quantum theory of atoms in molecules (QTAIM) analysis. Molecular dynamics simulations modeled benzodiazepine-adulterant/diluent systems, predicting the most stable structures, which were further analyzed using QTAIM. The strongest interactions and their effects on IR spectra were identified. Comparisons between experimental and theoretical spectra confirmed spectral changes due to interactions. This study demonstrates the potential of quantum chemical methods in analyzing complex mixtures, elucidating spectral changes, and assessing the structural stability of benzodiazepines in forensic samples.

New Psychoactive Substances: A Canadian perspective on emerging trends and challenges for the clinical laboratory

The production and use of New Psychoactive Substances (NPS) has skyrocketed over the last decade, causing major challenges for government authorities, public health agencies, and laboratories across the world. NPS are designed to mimic the psychoactive effects of unregulated or controlled drugs, while constantly being modified to evade drug control regulation. Hence, they are referred to as "legal highs", as they are technically legal to sell, possess, and use. NPS can be classified by their pharmacological mechanism of action and include cannabimimetic, depressants, dissociatives, hallucinogens, opioids, and stimulants. There is significant structural diversity within each NPS class, leading to variable detection using traditional clinical laboratory testing and complicating the interpretation of results. In this article, we review each of the NPS classes and summarize their associated mechanism of action, common structures, and metabolic pathways, and provide examples of recent drugs and emerging threats with a focus on Canadian drug trends. We also explore the current analytical advantages and limitations commonly faced by the clinical laboratory and provide insight on how toxicosurveillance can improve detection of NPS in the ever-changing NPS landscape.

Clinical detoxification of bromazolam using diazepam: a case report

An increasing number of new psychoactive substances (NPS), such as designer benzodiazepines, are becoming available on the recreational drug market. These are new unregistered substances and thereby an attempt to evade legislation. Often there is very limited clinical information available regarding these NPS, which could result in undesirable clinical outcomes in the management of intoxications, dependencies and withdrawals following NPS use. In this case report we describe a 23-year-old woman, who was admitted to our residential addiction care facility for the detoxification of the designer benzodiazepine bromazolam. Her daily use of 6 mg bromazolam was converted to 20 mg diazepam. Although we expected a higher dose would have been needed, 20 mg was sufficient and was tapered without complications. This case report demonstrates the safe conversion of 6 mg of bromazolam to 20 mg of diazepam by combining the use of fixed-dose and symptom-triggered-dose regimens. More clinical data is necessary to formulate advisory management for the detoxification of bromazolam and other designer benzodiazepines.

Discriminative stimulus and reinforcing effects of diclazepam in rodents

Diclazepam, a designer benzodiazepine, is a lesser-known novel anxiolytic substance and a structural analog of diazepam. Although several case studies have reported the adverse effects of diclazepam, their potential impacts remain unknown. Therefore, this study aimed to determine the effects of diclazepam in rodents using drug discrimination, locomotor activity, self-administration (SA), and conditioned place preference (CPP) tests. Sprague-Dawley rats (male, 8 weeks old, weighing 220-450 g, n = 12 per group) and C57BL/6 mice (male, 7 weeks old, weighing 20-25 g, n = 7-8 per group) were administered alprazolam, morphine, and diclazepam. Diclazepam fully elicited alprazolam-appropriate dose-dependent lever responses (>80 %) similar to those of alprazolam. In rats administered 0.5 mg/kg of morphine, a partial substitution (80 %-20 %) was observed. Mice receiving intraperitoneal injections of diclazepam (0.05, 0.2, and 2 mg/kg) showed decreased locomotor activity. In the SA experiment, mice that self-administered intravenous diclazepam (2 μg/kg/infusion) showed significantly higher infusion and active lever responses compared to the vehicle group. No statistically significant rewarding effects of diclazepam at the doses of 0.2 and 2 mg/kg evaluated using the CPP paradigm were found. In conclusion, diclazepam has reinforcing effects and shares the interoceptive effects of alprazolam. Therefore, legal restrictions on the use of diclazepam should be carefully considered.

Post mortem blood bromazolam concentrations and co-findings in 96 coronial cases within England and Wales

Bromazolam is a newly emerging benzodiazepine drug which is not licensed for medicinal use. It may be sourced as a New Psychoactive Substance (NPS) for its desired effects or be consumed unknowingly via counterfeit Xanax® or Valium® preparations. As part of our Coronial workload, we observed an increase in the detection of bromazolam from September 2021 to November 2022. We report a series of 96 cases in which bromazolam was quantitated by high resolution accurate mass - mass spectrometry (HRAM - MS) in post-mortem blood. The mean (SD) post-mortem blood bromazolam concentration from our case series was 64.6 ( ± 79.4) µg/L (range <1-425 µg/L). Routine toxicological screening results have also been reported; the most commonly encountered drugs taken in combination with bromazolam were cocaine, gabapentinoids and diazepam. In 48% of cases at least one further designer benzodiazepine drug was also present (etizolam, flualprazolam, flubromazolam, flubromazepam). It is essential that laboratories providing toxicological investigations are aware of the limitations of their assays; and inclusion of bromazolam within targeted screening panels using LC-MS/MS is encouraged. Bromazolam has not been associated with death in isolation from resulting toxic concentrations; however, it is likely to enhance adverse clinical effects when taken in combination with stimulant and/or centrally-acting depressant drugs (poly-drug deaths). Bromazolam, similar to other benzodiazepines, may also impair cognition and decision making skills.

Designer benzodiazepine dependence and the difficulties of outpatient management; a case report

BACKGROUND

Novel psychoactive substances, such as designer benzodiazepines (DBZD), are a growing public health concern. There are about 30 different DZBDs reported, which can vary widely in their effect and potential for harmful outcomes, ranging from agitation to confusion to coma. Despite the scope of this widespread phenomena, little information on the management of DBZD dependence is available in the literature.

CASE

In this case report, we present a patient with DBZD dependence requesting assistance tapering off the DBZD, clonazolam. He began self-medicating with clonazolam seven years prior for panic attacks to the point he was using 40 drops per day and having significant withdrawal during the day. He was prescribed gabapentin for his underlying anxiety while he tapered his clonazolam dose. Once he achieved a 75% reduction in his use of clonazolam, he had trouble managing withdrawal and anxiety symptoms and could not taper further.

DISCUSSION

We discuss the challenges of treating patients with DBZD use disorder in an outpatient setting. Switching a patient from a DZBD to a prescription benzodiazepine for the purposes of a taper can be dangerous as an outpatient due to the inability to monitor at-home DBZD usage and the resulting risk of overdose. DBZDs can also be highly potent and make it difficult to achieve success using current withdrawal guidelines.

Direct Access to Quinone-Fused 5-Substituted-1,4-Benzodiazepine Scaffolds from Azidoquinones with/without [1,2]-Azide-Nitrogen Migration: Mechanistic Insights

Seven-membered nitrogen heterocycles have a strong influence in drug discovery due to their inherent 3D character, which allows the ability to explore a vast conformational space with a biological target. Notably, the privileged 1,4-benzodiazepine scaffold is dominant in treating the central nervous system due to its binding affinity with the GABAA receptor. Herein, we report a protocol for the transformation of azidoquinones to p-quinone fused 5-substituted-1,4-benzodiazepines (p-QBZDs) from InCl3-catalyzed intermolecular tandem cycloannulation of azidoquinones with amines and aldehydes. Detailed mechanistic studies reveal that the EDA complex between azidoquinones and InCl3 is crucial in determining the reaction pathway. In the absence of EDA complex formation, the reaction proceeds via the intermediacy of 2,3-bridged-2H-azirine followed by regiospecific addition of an amine to C═N/ring opening/cyclization to deliver p-QBZD with 1,2-azide-nitrogen migration. In the case of EDA complex formation, the reaction proceeds through regioselective aza-Michael addition/nitrene insertion with aldehyde and subsequent cyclization to deliver p-QBZD and p-quinone fused imidazole as a secondary product without 1,2-azide-nitrogen migration. This protocol provides straightforward access to redox-active quinone embedded 5-substituted-1,4-benzodiazepines from azidoquinones with diverse substrate scopes that would find potential applications in medicinal chemistry and drug discovery.

Long-term consequences of benzodiazepine-induced neurological dysfunction: A survey

BACKGROUND

Acute benzodiazepine withdrawal has been described, but literature regarding the benzodiazepine-induced neurological injury that may result in enduring symptoms and life consequences is scant.

OBJECTIVE

We conducted an internet survey of current and former benzodiazepine users and asked about their symptoms and adverse life events attributed to benzodiazepine use.

METHODS

This is a secondary analysis of the largest survey ever conducted with 1,207 benzodiazepine users from benzodiazepine support groups and health/wellness sites who completed the survey. Respondents included those still taking benzodiazepines (n = 136), tapering (n = 294), or fully discontinued (n = 763).

RESULTS

The survey asked about 23 specific symptoms and more than half of the respondents who experienced low energy, distractedness, memory loss, nervousness, anxiety, and other symptoms stated that these symptoms lasted a year or longer. These symptoms were often reported as de novo and distinct from the symptoms for which the benzodiazepines were originally prescribed. A subset of respondents stated that symptoms persisted even after benzodiazepines had been discontinued for a year or more. Adverse life consequences were reported by many respondents as well.

LIMITATIONS

This was a self-selected internet survey with no control group. No independent psychiatric diagnoses could be made in participants.

CONCLUSIONS

Many prolonged symptoms subsequent to benzodiazepine use and discontinuation (benzodiazepine-induced neurological dysfunction) have been shown in a large survey of benzodiazepine users. Benzodiazepine-induced neurological dysfunction (BIND) has been proposed as a term to describe symptoms and associated adverse life consequences that may emerge during benzodiazepine use, tapering, and continue after benzodiazepine discontinuation. Not all people who take benzodiazepines will develop BIND and risk factors for BIND remain to be elucidated. Further pathogenic and clinical study of BIND is needed.

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.

Designer benzodiazepines: an update

INTRODUCTION

Designer benzodiazepines (DBs) are a subclass of novel psychoactive substances (NPS). DBs mimic the properties of approved and prescribed benzodiazepines.

AREA COVERED

A systematic search of literature on DB classification, structure-activity relationships, pharmacologic properties, and adverse effects.

EXPERT OPINION

The prevalence of DB use has increased substantially over the last decade. All DBs are full-agonist ligands at the gamma-aminobutyric acid type A-benzodiazepine (GABA_A-BZ) receptor system. This is not surprising, since DBs largely represent either minor structural modifications, or well-recognized active metabolites, of existing approved benzodiazepines. As such, the pharmacologic profile and associated risks and hazards of DBs are similar or identical to clinically approved and legitimately prescribed benzodiazepines, most of which have been in use for decades. Concurrent use of DBs along with other abusable or recreational drugs (alcohol, opioids, cocaine, stimulants, hallucinogens, other sedative-hypnotics) represents the principal public health risk. The increasing illicit availability and use of DBs is of concern and requires regulatory attention, but DBs do not rank highly among designer psychotropic agents in terms of health risk to humans.

Metabolic profiling of clonazolam in human liver microsomes and zebrafish models using liquid chromatography quadrupole Orbitrap mass spectrometry

Clonazolam is a designer benzodiazepine with strong sedative and amnesic effects. As we all know, the detection of metabolites is the key to confirming the use of substances in the field of forensic toxicology. In order to better describe clonazolam metabolism completely, we performed the two different experiments exploiting the unique characteristics of the models used. In this study, in vivo and in vitro samples were analyzed with liquid chromatography-quadrupole/electrostatic field orbitrap mass spectrometry. The results showed that seven Phase I metabolites and one Phase II metabolite were detected in zebrafish model. The remaining Phase I and II metabolites were also found in the incubation solution of pooled human liver microsomes. The main types of metabolic reactions of clonazolam included hydroxylation, dealkylation, nitroreduction, dechlorination, N-Acetylation, and O-glucuronidation. In this paper, the main metabolites and metabolic pathways of clonazolam are clarified in detail in order to further improve the metabolic rule of clonazolam. Based on these results, to better detect and judge the abuse of clonazolam, we suggest that M1, its nitro reduction product, is used as its biomarker. The results of this study provide a theoretical basis for the pharmacokinetics and forensic medicine of clonazolam.

Environmental concentrations of a delorazepam-based drug impact on embryonic development of non-target Xenopus laevis

Benzodiazepines, psychotropics drugs used for treating sleep disorders, anxiety and epilepsy, represent a major class of emerging water pollutants. As occurs for other pharmaceutical residues, they are not efficiently degraded during sewage treatment and persist in effluent waters. Bioaccumulation is already reported in fish and small crustaceans, but the impact and consequences on other "non-target" aquatic species are still unclear and nowadays of great interest. In this study, we investigated the effects of a pharmaceutical preparation containing the benzodiazepine delorazepam on the embryogenesis of Xenopus laevis, amphibian model species, taxa at high risk of exposure to water contaminants. Environmental (1 μg/L) and two higher (5 and 10 μg/L) concentrations were tested on tadpoles up to stage 45/46. Results demonstrate that delorazepam interferes with embryo development and that the effects are prevalently dose-dependent. Delorazepam reduces vitality by decreasing heart rate and motility, induces marked cephalic and abdominal edema, as well as intestinal and retinal defects. At the molecular level, delorazepam increases ROS production, modifies the expression of some master developmental genes and pro-inflammatory cytokines. The resulting stress condition significantly affects embryos' development and threatens their survival. Similar effects should be expected as well in embryos belonging to other aquatic species that have not been yet considered targets for these pharmaceutical residues.

Novel Designer Benzodiazepines: Comprehensive Review of Evolving Clinical and Adverse Effects

As tranquilizers, benzodiazepines have a wide range of clinical uses. Recently, there has been a significant rise in the number of novel psychoactive substances, including designer benzodiazepines. Flubromazolam(8-bromo-6-(2-fluorophenyl)-1-methyl-4H-[1,2,4]triazolo[4,3-a][1,4]benzodiazeZpine) is a triazolo-analogue of flubromazepam. The most common effects noted by recreational users include heavy hypnosis and sedation, long-lasting amnesia, and rapid development of tolerance. Other effects included anxiolysis, muscle-relaxing effects, euphoria, loss of control, and severe withdrawals. Clonazolam, or 6-(2-chlorophenyl)-1-methyl-8-nitro-4H-[1,2,4]triazolo[4,3-α]-[1,4]-benzodiazepine, is a triazolo-analog of clonazepam. It is reported to be over twice as potent as alprazolam. Deschloroetizolam (2-Ethyl-9-methyl-4-phenyl-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepine) is part of the thienodiazepine drug class, which, like benzodiazepines, stimulates GABA-A receptors. Meclonazepam ((3S)-5-(2-chlorophenyl)-3-methyl-7-nitro-1,3-dihydro-1,4-benzodiazepin-2-one) is a designer benzodiazepine with additional anti-parasitic effects. Although it has proven to be an efficacious therapy for schistosomiasis, its sedative side effects have prevented it from being marketed as a therapeutic agent. The use of DBZs has been a subject of multiple recent clinical studies, likely related to increasing presence and availability on the internet drug market and lack of regulation. Many studies have aimed to identify the prevalence of DBZs and their effects on those using them. This review discussed these designer benzodiazepines and the dangers and adverse effects that the clinician should know.

The designer benzodiazepine, flubromazepam, induces reward-enhancing and cardiotoxic effects in rodents

The use of many benzodiazepines is controlled worldwide due to their high likelihood of abuse and potential adverse effects. Flubromazepam—a designer benzodiazepine—is a long-acting gamma-aminobutyric acid subtype A receptor agonist. There is currently a lack of scientific evidence regarding the potential for flubromazepam dependence or other adverse effects. This study aimed to evaluate the dependence potential, and cardiotoxicity via confirmation of the QT and RR intervals which are the factors on the electrical properties of the heart of flubromazepam in rodents. Using a conditioned place preference test, we discovered that mice treated intraperitoneally with flubromazepam (0.1 mg/kg) exhibited a significant preference for the flubromazepam-paired compartment, suggesting a potential for flubromazepam dependence. In addition, we observed several cardiotoxic effects of flubromazepam; 100-μM flubromazepam reduced cell viability, increased RR intervals but not QT intervals in the electrocardiography measurements, and considerably inhibited potassium channels in a human ether-à-go-go-related gene assay. Collectively, these findings suggest that flubromazepam may have adverse effects on psychological and cardiovascular health, laying the foundation for further efforts to list flubromazepam as a controlled substance at both national and international levels.

The alprazolam analogue 4'-chloro deschloroalprazolam identified in seized capsules

New designer benzodiazepines continue to be identified in the illicit drug market. In December 2021, eight capsules were submitted to ChemCentre for analysis. The samples were analysed by a range of analytical techniques including gas chromatography-mass spectrometry (GC-MS), ultraviolet-visible spectrophotometry, liquid chromatography-mass spectrometry (LC-MS, low and high resolution), nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography, which identified the main component of the capsules to be 4'-chloro deschloroalprazolam, a new designer benzodiazepine. Alarmingly, the mass spectral data for this alprazolam analogue were very similar to that of alprazolam, such that misidentification could be possible. A minor component of the capsules was also partially characterised, it is believed to be the synthetic precursor 4'-chloro deschloronordiazepam. The information provided in this paper includes ways to discriminate these analogues from alprazolam and nordiazepam which will enable other laboratories to identify these new drugs.

Challenges of Diagnosing and Managing Designer Benzodiazepine Dependence and Withdrawal: A Case Report

BACKGROUND

Over the last 10 years, an increasing number of unregulated novel psychoactive substances, including "designer benzodiazepines" (DBZDs), have emerged on the recreational drug market. Despite the rapidly increasing usage of DBZDs, there is a significant lack of information regarding clinical management. Here we present a case illustrating the difficulties of diagnosing and managing DBZD related sedative-hypnotic use disorder.

CASE PRESENTATION

Our patient is a 30-year-old man with severe opioid and sedative-hypnotic use disorders. He had a 10-year history of using heroin, clonazolam, and alprazolam. He stopped using heroin when on methadone maintenance therapy but continued using clonazolam and nonprescribed alprazolam. His opioid treatment program discontinued methadone due to benzodiazepine intoxication, and he returned to heroin use. He then presented for residential withdrawal management where he underwent successful buprenorphine induction and benzodiazepine withdrawal management. During a 3-month period of benzodiazepine abstinence, he struggled with ongoing cravings and post-acute withdrawal syndrome, ultimately leading to return to DBZD use.

DISCUSSION

Despite the increasing prevalence of DBZD use, the usage of DBZDs is likely under-recognized because these compounds are generally not included on standard in-office urine drug immunoassay tests. Initial studies suggest that DBZDs have high potencies, shorter half-lives, are more addictive, and can result in more severe withdrawal symptoms compared to known benzodiazepines. However, there remains a lack of information about the pharmacokinetics and pharmacodynamics of DBZDs, making clinical management for DBZD related sedative-hypnotic use disorders challenging to treat.

Significant toxicity following an increase in poisonings with designer benzodiazepines in the Netherlands between 2010 and 2020

BACKGROUND

Designer benzodiazepines (DBs) are an emerging class of new psychoactive substances. While structurally derived from pharmaceutical benzodiazepines, their toxicological profile is less clear. We investigated time trends in the rate of DB poisonings and their clinical toxicity.

METHODS

A retrospective observational study was performed on the incidence rate of DB poisonings, relative to all recreational drug poisonings reported to the Dutch Poisons Information Center (DPIC) from 2010 to 2020. Time-trend analysis was performed using Poisson regression. A prospective cohort study was performed on toxicity of DBs, including the Poisoning Severity Score, from January 2016-June 2019. Data was collected through telephone interviews.

RESULTS

Between 2010 and 2020, the DPIC was consulted on 142 DB exposures. The incidence rate of DB exposures increased from 0.1% to 4.3%, with a year effect estimate of 1.35 (95% CI [1.14;1.54]). Twenty different DBs were reported, mostly etizolam (33%), clonazolam (17%), and flunitrazolam (8%). During consultation (often shortly after exposure), poisoning was graded moderate-severe in 29% of cases (n = 146). In the prospective cohort sample with follow-up (n = 22), 86% of cases (n = 19) showed a moderate-severe poisoning. The severity of poisoning did not differ between mono- and mixed intoxications. Frequently reported symptoms in the prospective cohort sample included drowsiness (86%), confusion (59%), and agitation (55%). Coma was observed in seven cases (32%) and respiratory depression requiring mechanical ventilation in five cases (23%).

CONCLUSION

The rate of DB poisonings reported to the DPIC strongly increased from 2010 to 2020, indicating increased (ab)use of DBs. Most DB exposures resulted in moderate-severe toxicity with neurological effects.

Formation and occurrence of disinfection byproducts of benzodiazepine drug estazolam in drinking water of Beijing

Estazolam (EZ) is a long-acting benzodiazepine (BZD) drug with high clinical consumption in China to treat anxiety, depression and other syndromes. Recently, it has been found as a leading potentially inappropriate medication among hospitalized elderly patients, increasing the risk of falls. It is discharged into the aquatic environment after use and has been frequently detected, ultimately affecting the safety of drinking water. In the present study, the reaction of EZ during chlorination disinfection was investigated in detail with regard to its transformation and kinetics. By means of ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS), four main disinfection byproducts (DBPs) were tentatively identified, and the transformation pathways were speculated to be cleavage at the imine linkage and oxidation on the diazepinone ring. The chlorination reaction rate in the pseudo-first-order kinetic model was significantly affected by free available chlorine (FAC) and pH. The increase in pH value led to a decrease in the reaction rate, while a higher dosage of chlorine resulted in a faster kinetic rate. We further estimated the potential toxicities of EZ and its DBPs using quantitative structure-activity relationship (QSAR) software tools. DBPs exhibited much higher toxicity than EZ and exhibited developmental toxicity and mutagenicity. Finally, a total of 108 drinking water samples were collected in the wet and dry seasons to determine actual residue changes in real environmental conditions. The detection frequency was 29% for EZ, and the highest concentration of 0.60 ng L^-1 was found for its DBPs in tap water. No seasonal variations in concentration were observed. Overall, the results indicate that EZ and its DBPs may persist in drinking water, posing potential risks to public health.

The blood-to-plasma ratio and predicted GABAA-binding affinity of designer benzodiazepines

PURPOSE

The number of benzodiazepines appearing as new psychoactive substances (NPS) is continually increasing. Information about the pharmacological parameters of these compounds is required to fully understand their potential effects and harms. One parameter that has yet to be described is the blood-to-plasma ratio. Knowledge of the pharmacodynamics of designer benzodiazepines is also important, and the use of quantitative structure-activity relationship (QSAR) modelling provides a fast and inexpensive method of predicting binding affinity to the GABA_A receptor.

METHODS

In this work, the blood-to-plasma ratios for six designer benzodiazepines (deschloroetizolam, diclazepam, etizolam, meclonazepam, phenazepam, and pyrazolam) were determined. A previously developed QSAR model was used to predict the binding affinity of nine designer benzodiazepines that have recently appeared.

RESULTS

Blood-to-plasma values ranged from 0.57 for phenazepam to 1.18 to pyrazolam. Four designer benzodiazepines appearing since 2017 (fluclotizolam, difludiazepam, flualprazolam, and clobromazolam) had predicted binding affinities to the GABA_A receptor that were greater than previously predicted binding affinities for other designer benzodiazepines.

CONCLUSIONS

This work highlights the diverse nature of the designer benzodiazepines and adds to our understanding of their pharmacology. The greater predicted binding affinities are a potential indication of the increasing potency of designer benzodiazepines appearing on the illicit drugs market.

Flualprazolam distribution in postmortem samples

The constant emergence of novel psychoactive substances is troubling to both public health officials and legislators. Additionally, sufficient data collection for each new compound can take months up to years. Flualprazolam, a triazolobenzodiazepine, quickly garnered attention as a sedative drug that likely expresses adverse reactions similarly to alprazolam. This study focuses on the distribution of flualprazolam in multiple common postmortem matrices. Central blood, vitreous humor, liver homogenate, brain homogenate, gastric contents, and urine samples from death investigation cases were quantitated when available. Samples were screened with liquid chromatography quadrupole time-of-flight with limit of detection set at 4 ng/ml and quantitated on liquid chromatography tandem mass spectrometry, with concentration range from 4 to 256 ng/ml. From August 2018 to September 2020, 24 central blood samples were quantitated for flualprazolam. Central bloods of 22 cases had concentrations above the limit of quantitation. The average flualprazolam central blood concentration was 16.3 ng/ml with a median of 9.95 ng/ml (4.24-48.0). Additional analyses for unconjugated flualprazolam were performed on at a total of 15 urine samples ( x ¯  = 14.4, 4.07-36.1 ng/ml), 23 brain homogenates ( x ¯  = 23.2, 3.99-69.3 ng/g), 23 liver homogenates ( x ¯  = 50.7, 13.6-156 ng/g), five vitreous humor samples ( x ¯  = 7.70, 4.03-12 ng/ml), and 12 gastric contents samples ( x ¯  = 0.36, 0.02-2.51 mg). The cause of death for 13 of the 24 cases listed flualprazolam as a contributing factor of death.

The Psychonauts' Benzodiazepines; Quantitative Structure-Activity Relationship (QSAR) Analysis and Docking Prediction of Their Biological Activity

Designer benzodiazepines (DBZDs) represent a serious health concern and are increasingly reported in polydrug consumption-related fatalities. When new DBZDs are identified, very limited information is available on their pharmacodynamics. Here, computational models (i.e., quantitative structure-activity relationship/QSAR and Molecular Docking) were used to analyse DBZDs identified online by an automated web crawler (NPSfinder^®) and to predict their possible activity/affinity on the gamma-aminobutyric acid A receptors (GABA-ARs). The computational software MOE was used to calculate 2D QSAR models, perform docking studies on crystallised GABA-A receptors (6HUO, 6HUP) and generate pharmacophore queries from the docking conformational results. 101 DBZDs were identified online by NPSfinder^®. The validated QSAR model predicted high biological activity values for 41% of these DBDZs. These predictions were supported by the docking studies (good binding affinity) and the pharmacophore modelling confirmed the importance of the presence and location of hydrophobic and polar functions identified by QSAR. This study confirms once again the importance of web-based analysis in the assessment of drug scenarios (DBZDs), and how computational models could be used to acquire fast and reliable information on biological activity for index novel DBZDs, as preliminary data for further investigations.

What's in fake 'Xanax'?: A dosage survey of designer benzodiazepines in counterfeit pharmaceutical tablets

The identification of a range of different drugs within counterfeit benzodiazepine tablets has been widely reported; however, limited information is available on the dosage of these products. A rapid dosage survey of 46 counterfeit benzodiazepine tablets from 20 seizures was conducted over a 6-month period between April and September 2020. Existing methods utilised for the determination of benzodiazepines in toxicology specimens were applied to assess the dosage of four benzodiazepines detected across five different counterfeit benzodiazepine presentations. The highest dosage variation was observed for etizolam with a range of 0.7-8.3 mg per tablet. This report demonstrates the variability in drug content and dosage that can occur between visually similar counterfeit tablets, even when co-packaged within the same seizure, highlighting the potential public harm posed by these counterfeit medications.

Designer Benzodiazepines: A Review of Toxicology and Public Health Risks

The rising use of designer benzodiazepines (DBZD) is a cat-and-mouse game between organized crime and law enforcement. Non-prohibited benzodiazepines are introduced onto the global drug market and scheduled as rapidly as possible by international authorities. In response, DBZD are continuously modified to avoid legal sanctions and drug seizures and generally to increase the abuse potential of the DBZD. This results in an unpredictable fluctuation between the appearance and disappearance of DBZD in the illicit market. Thirty-one DBZD were considered for review after consulting the international early warning database, but only 3-hydroxyphenazepam, adinazolam, clonazolam, etizolam, deschloroetizolam, diclazepam, flualprazolam, flubromazepam, flubromazolam, meclonazepam, phenazepam and pyrazolam had sufficient data to contribute to this scoping review. A total of 49 reports describing 1 drug offense, 2 self-administration studies, 3 outpatient department admissions, 44 emergency department (ED) admissions, 63 driving under the influence of drugs (DUID) and 141 deaths reported between 2008 and 2021 are included in this study. Etizolam, flualprazolam flubromazolam and phenazepam were implicated in the majority of adverse-events, drug offenses and deaths. However, due to a general lack of knowledge of DBZD pharmacokinetics and toxicity, and due to a lack of validated analytical methods, total cases are much likely higher. Between 2019 and April 2020, DBZD were identified in 48% and 83% of postmortem and DUID cases reported to the UNODC, respectively, with flualprazolam, flubromazolam and etizolam as the most frequently detected substances. DBZD toxicology, public health risks and adverse events are reported.

Detection of flubromazolam in patients with suspected non-medical drug use attending emergency departments in the United Kingdom

INTRODUCTION

Non-medical use of novel benzodiazepines has recently become common. Here, we describe the recent frequent detection of flubromazolam in patients attending United Kingdom emergency departments.

METHODS

Adults presenting to participating hospitals with toxicity after suspected drug misuse were studied between March 2015 and January 2021. Clinical features were recorded using consistent methodology and biological samples analysed using liquid chromatography-tandem mass-spectrometry.

RESULTS

Flubromazolam and/or its mono-hydroxylated metabolite were detected in samples from 14 of 957 patients, all presenting since July 2020. Reported clinical features included reduced level of consciousness (10), confusion/agitation (6) and acidosis (5) but multiple other substances were detected in all patients. All patients survived to discharge (length of hospital stay 3.0 to 213 h, median 24.1 h). There was no correlation between admission blood/serum flubromazolam concentrations (range 1.7-480.5 ng/ml, median 7.4 ng/ml) and Glasgow Coma Scale or length of hospital stay. In one patient who needed intubation and ventilation for five days, there was an exponential decline in flubromazolam concentrations with time (calculated half-life 39.8 h). Hydroxyl-flubromazolam was also identified at all time points.

CONCLUSIONS

Flubromazolam has been detected frequently in drug users presenting to UK emergency departments since July 2020. Prolonged toxicity may occur as a result of the long half-life of flubromazolam and the production of metabolites likely to be active.

Designer benzodiazepines versus prescription benzodiazepines: can structural relation predict the next step?

Designer benzodiazepines are a part of the recently discovered abuse synthetic drugs called Novel Psychoactive Substances (NPS) which need to be controlled due to their constantly growing market. Most of them are derived from the medically approved benzodiazepines used nowadays yet, may possess stronger effects, more toxicity, and longer durations of action. Some differences have also been observed in their detection and characteristics, in addition to the variations discovered in postmortem redistribution and drug stability. All these major alterations in features can result from only minor structural modifications. For example, a classic benzodiazepine (BZD) like diazepam only lacks one fluorine atom which exists in its derivatized designer drug, diclazepam, making substantial differences in activity. For this reason, it is essential to study the designer drugs in order to identify their dangers and distinguish them thus rule out their abuse and control the spread of such drugs. This review would highlight the distinct characteristics of some of the most commonly abused designer benzodiazepine analogies in relation to their original prescription BZD compounds.

Quantification of Flualprazolam in Blood by LC-MS-MS: A Case Series of Nine Deaths

The emergence of novel designer benzodiazepines continues to be a public health concern. Flualprazolam is one of these drugs. It was initially identified in 2017. User forums suggest it is slightly more potent than alprazolam and has longer-lasting central nervous system depressant effects. Here we report a simple, sensitive liquid chromatography-tandem mass spectrometry method for flualprazolam and report a series of nine cases in which flualprazolam was quantified. As is typical of forensic toxicology in the twenty-first century, all the cases had more than one drug present. None of the deaths could be directly attributed to flualprazolam alone, but all were likely due to a combination of sedative drugs. However, this paper still adds to the data available to allow interpretation of postmortem flualprazolam concentrations.

Quantification of 54 Benzodiazepines and Z-Drugs, Including 20 Designer Ones, in Plasma

Benzodiazepines are widely used in the treatment of sleep and anxiety disorders, as well as epileptic seizures and alcohol withdrawal because of their broad therapeutic index and low cost. Due to their central nervous system depressant effects they are also often implicated in traffic accidents and drug-related intoxications. With an increasing number of designer benzodiazepines used in a recreational setting, there is a need for analytical methods to be able to quantify both the prescribed and designer benzodiazepines. A liquid chromatography-triple quadrupole mass spectrometry method was developed for the quantification of 34 prescribed and 20 designer benzodiazepines in plasma. Different sample preparation strategies, including protein precipitation, liquid-liquid extraction, solid-phase extraction and mini-QuEChERS, were tested. The best recoveries for all compounds of interest were obtained with a liquid-liquid extraction using methyl-tertiary-butyl-ether and 500 μL plasma. The method was fully validated according to the European Medicines Agency guidelines for all compounds, except pivoxazepam, which is included for qualitative purposes only. In-sample stability issues were observed for cloxazolam, both at ambient temperature and during long-term storage at -20°C. Due to the large number of compounds included, the simple and time-efficient sample preparation and the relatively inexpensive instrumentation used, the presented method can be readily implemented in both therapeutic drug monitoring and forensic analyses.

Overview of the major classes of new psychoactive substances, psychoactive effects, analytical determination and conformational analysis of selected illegal drugs

The misuse of psychoactive substances is attracting a great deal of attention from the general public. An increase use of psychoactive substances is observed among young people who do not have enough awareness of the harmful effects of these substances. Easy access to illicit drugs at low cost and lack of effective means of routine screening for new psychoactive substances (NPS) have contributed to the rapid increase in their use. New research and evidence suggest that drug use can cause a variety of adverse psychological and physiological effects on human health (anxiety, panic, paranoia, psychosis, and seizures). We describe different classes of these NPS drugs with emphasis on the methods used to identify them and the identification of their metabolites in biological specimens. This is the first review that thoroughly gives the literature on both natural and synthetic illegal drugs with old known data and very hot new topics and investigations, which enables the researcher to use it as a starting point in the literature exploration and planning of the own research. For the first time, the conformational analysis was done for selected illegal drugs, giving rise to the search of the biologically active conformations both theoretically and using lab experiments.

A fluorine turns a medicinal benzodiazepine into NPS: the case of flualprazolam

Purpose

The purpose of this review is to summarize the existing knowledge on flualprazolam, a novel ‘designer’ benzodiazepine that derives from the fluorination of the phenyl moiety in the ortho-position of alprazolam.

Methods

An extensive literature search was carried out in PubMed, Google Scholar and World Wide Web using relevant keywords. All articles found were gathered, and the available information is presented.

Results

This article reviews the existing knowledge on chemistry, pharmacology, toxicology, prevalence and current legal status of flualprazolam. Moreover, forensic and clinical cases where flualprazolam was involved worldwide, as well as flualprazolam seizures, along with the methods for its determination in biological samples are presented.

Conclusions

The recent flualprazolam-related cases have raised concerns to regulatory authorities and international stakeholders suggesting that flualprazolam should be under international control. The urgent international control of flualprazolam, despite the limited information on clinical effects and pharmacologic characteristics available, is an important measure for the prevention of its increasing abuse worldwide.

Blood Concentrations of Designer Benzodiazepines: Relation to Impairment and Findings in Forensic Cases

The use of designer benzodiazepines appears to be increasing in many countries, but data concerning blood concentrations are scarce, making interpretation of concentrations difficult. The aim of this study was to report blood concentrations of clonazolam, diclazepam, etizolam, flualprazolam, flubromazepam, flubromazolam and phenazepam and to investigate the relationship between blood concentrations and impairment. The concentration data are from blood samples collected from living cases (apprehended drivers and other drug offences) and medico-legal autopsies. The blood samples were analysed for the seven designer benzodiazepines mentioned above by ultra high performance liquid chromatography–tandem mass spectrometry. Positive cases from between 1 June 2016 and 30 September 2019 were included. Blood concentrations and the conclusion from a clinical test of impairment (when available) are reported. The presented seven benzodiazepines were detected in a total of 575 cases, where 554 of these cases concerned apprehended drivers or other criminal offenders. The number of findings and the median (range) concentrations were as follows: clonazolam, n = 22, 0.0041 mg/L (0.0017–0.053 mg/L); diclazepam, n = 334, 0.0096 mg/L (0.0016–0.25 mg/L); etizolam, n = 40, 0.054 mg/L (0.015–0.30 mg/L); flualprazolam, n = 10, 0.0080 mg/L (0.0033–0.056 mg/L); flubromazepam, n = 5, 0.037 mg/L (0.0070–0.70 mg/L); flubromazolam, n = 20, 0.0056 mg/L (0.0004–0.036 mg/L); and phenazepam, n = 138, 0.022 mg/L (0.0018–0.85 mg/L). A designer benzodiazepine was the only drug detected with relevance for impairment in 25 of the 554 living cases. The physician concluded with impairment in 19 of the 25 cases. Most of the concentrations in these cases were relatively similar to or higher than the median reported concentrations. The most frequent other drugs detected were amphetamine, tetrahydrocannabinol, clonazepam and methamphetamine. The presented blood concentrations can be helpful with the interpretation of cases involving one or more of these seven benzodiazepines. The results indicate that concentrations commonly observed in forensic cases are associated with impairment.

New psychoactive substances: a review and updates

New psychoactive substances (NPS) are a heterogeneous group of substances. They are associated with a number of health and social harms on an individual and societal level. NPS toxicity and dependence syndromes are recognised in primary care, emergency departments, psychiatric inpatient and community care settings. One pragmatic classification system is to divide NPS into one of four groups: synthetic stimulants, synthetic cannabinoids, synthetic hallucinogens and synthetic depressants (which include synthetic opioids and benzodiazepines). We review these four classes of NPS, including their chemical structures, mechanism of action, modes of use, intended intoxicant effects, and their associated physical and mental health harms. The current challenges faced by laboratory testing for NPS are also explored, in the context of the diverse range of NPS currently available, rate of production and emergence of new substances, the different formulations, and methods of acquisition and distribution.

Recent bionalytical methods for the determination of new psychoactive substances in biological specimens

One of the problems associated with the consumption of new psychoactive substances is that in most scenarios of acute toxicity the possibility of quick clinical action may be impaired because many screening methods are not responsive to them, and laboratories are not able to keep pace with the appearance of new substances. For these reasons, developing and validating new analytical methods is mandatory in order to efficiently face those problems, allowing laboratories to be one step ahead. The goal of this work is to perform a critical review regarding bionalytical methods that can be used for the determination of new psychoactive substances (phenylethylamines, cathinones, synthetic cannabinoids, opioids, benzodiazepines, etc), particularly concerning sample preparation techniques and associated analytical methods.

Flubromazolam-Derived Designer Benzodiazepines: Toxicokinetics and Analytical Toxicology of Clobromazolam and Bromazolam

Flubromazolam is widely known as highly potent designer benzodiazepine (DBZD). Recently, the two flubromazolam-derived new psychoactive substances (NPS) clobromazolam and bromazolam appeared on the drugs of abuse market. Since no information concerning their toxicokinetics in humans is available, the aims of the current study were to elucidate their metabolic profile and to identify the isozymes involved in their phase I and phase II metabolism. In vitro incubations with pooled human liver S9 fraction were performed and analyzed by liquid chromatography coupled to orbitrap-based high-resolution tandem mass spectrometry (LC–HRMS-MS). Biosamples after the ingestion of bromazolam allowed the identification of metabolites in human plasma and urine as well as the determination of bromazolam plasma concentrations by LC–HRMS-MS using the standard addition method. In total, eight clobromazolam metabolites were identified in vitro as well as eight bromazolam metabolites in vitro and in vivo. Predominant metabolic steps were hydroxylation, glucuronidation and combinations thereof. Alpha-hydroxy bromazolam glucuronide and bromazolam N-glucuronide are recommended as screening targets in urine. Bromazolam and its alpha-hydroxy metabolite are recommended if conjugate cleavage is part of the sample preparation procedure. The bromazolam plasma concentrations were determined to be 6 and 29 μg/L, respectively. Several cytochrome P450 (CYP) and uridine 5'-diphospho-glucuronosyltransferase (UGT) isozymes were shown to catalyze their metabolic transformations. CYP3A4 was involved in the formation of all phase I metabolites of both NPS, while UGT1A4 and UGT2B10 catalyzed their N-glucuronidation. Several UGT isoforms catalyzed the glucuronidation of the hydroxy metabolites. In conclusion, the determined bromazolam plasma concentrations in the low micrograms per liter range underlined the need for sensitive analytical methods and the importance of suitable urine screening procedures including DBZD metabolites as targets. Such an analytical strategy should be also applicable for clobromazolam.

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.

Toxicokinetics and Analytical Toxicology of Flualprazolam: Metabolic Fate, Isozyme Mapping, Human Plasma Concentration and Main Urinary Excretion Products

An increasing number of benzodiazepine-type compounds are appearing on the new psychoactive substances market. 8-Chloro-6-(2-fluorophenyl)-1-methyl-4H-[1,2,4]triazolo[4,3-a][1,4]benzodiazepine (well known as flualprazolam) represents a potent ‘designer benzodiazepine’ that has been associated with sedation, loss of consciousness, memory loss and disinhibition. The aims of the present study were to tentatively identify flualprazolam metabolites using in vitro incubations with pooled human liver S9 fraction or HepaRG cells by means of liquid-chromatography-high resolution tandem mass spectrometry. Isozymes involved in phase I and II biotransformation were identified in vitro. Results were then confirmed using human biosamples of an 18-year old male who was admitted to the emergency department after suspected flualprazolam ingestion. Furthermore, the plasma concentration was determined using the standard addition method. Seven flualprazolam metabolites were tentatively identified. Several cytochrome P450 and UDP-glucuronosyltransferase isozymes, amongst them CYP3A4 and UGT1A4, were shown to be involved in flualprazolam biotransformation reactions, and an influence of polymorphisms as well as drug–drug or drug–food interactions cannot be excluded. Alpha-hydroxy flualprazolam glucuronide, 4-hydroxy flualprazolam glucuronide and the parent glucuronide were identified as most abundant signals in urine, far more abundant than the parent compound flualprazolam. These metabolites are thus recommended as urine-screening targets. If conjugate cleavage was performed during sample preparation, the corresponding phase I metabolites should be added as targets. Both hydroxy metabolites can also be recommended for blood screening. The flualprazolam plasma concentration determined in the intoxication case was as low as 8 μg/L underlining the need of analytical methods with sufficient sensitivity for blood-screening purposes.

'New/Designer Benzodiazepines': An Analysis of the Literature and Psychonauts' Trip Reports

BACKGROUND

NPS belonging to the benzodiazepine (BZD) class, e.g., 'legal/designer BZDs'/'research chemicals', have recently emerged in the drug (mainly online/virtual) market.

OBJECTIVE

While certain NPS belonging to the BZD class possess pharmacological profiles similar to controlled pharmaceutical BZDs, clinical and pharmacological profiles of current emerging BZDs are still not well-described. Therefore, there is a need to increase clinicians'/public health knowledge/awareness, to incentive harm reduction strategies.

METHOD

A comprehensive overview was carried out by using the EMCDDA/EDND database regularly monitored by our research team, by specifically looking at the 'new BZDs' so far notified. Furthermore, given the limitation of peer-reviewed data published so far, a nonparticipant multilingual qualitative netnographic study was conducted to obtain further clinical/pharmacological/ toxicological data, including psychonauts' online trip reports.

RESULTS

First designer BZDs appeared as NPS around 2007. So far, 29 designer BZDs have been notified to the EMCDDA, being some of them extremely powerful, also at lower dosages. They are sold as tablets/powder/pellets/capsules/blotters/liquids, at very affordable prices, and variably administered. Some are also sold on the illicit drugmarket as counterfeit forms of traditional BZDs or as either adulterants or diluents in heroin or other synthetic opioids/cannabinoids. Nowadays, there is no guarantee of the quality of designer BZDs composition/purification and, hence, most NPS consumers may be inadvertently exposed to unsafe and harmful compounds.

CONCLUSION

Given the limited information on their pharmacology/toxicity, variations in dosage, onset of effects, combination of substances, potency, and general patient or individual variability, the concomitant use of these substances with other drugs entails several and unpredictable risks.

Reactions of [2-(Bromomethyl)phenyl](4-chlorophenyl)methanone: A New Synthesis of [1,3]Thiazolo[3,2-b][2,4]benzodiazepine, Benzimidazo[1,2-b][2,4]benzodiazepine and Benzimidazo[1,2-b][2]benzazepine Derivatives

A new approach to the development of a number of azolo-condensed azepines and diazepines has been proposed. The method for the synthesis of [1,3]thiazolo[3,2-b][2,4]benzodiazepine, benzimidazo[1,2-b][2,4]benzodiazepineandbenzimidazo[1,2-b][2]benzazepinederivatives involves the reaction of [2-(bromomethyl)phenyl](4-chlorophenyl)methanonewith5-methyl-1,3-thiazol-2-amine, 1H-benzimidazol-2-amineand1,2-dimethyl-1H-benzimidazole. The formation of the quaternary salt of the initial diazole has been done under mild conditions in MeCN. The following intramolecular condensation has been realized by heating 2-amino azolium salts in AcOH or in Et3N as in the case of 2-methyl azolium salt. The structures of these cyclic compounds have been confirmed by mass spectrometry measurements, elemental analysis and NMR spectra.