Analysis on dynamic changes of etizolam and its metabolites and exploration of its development prospect using UPLC-Q-exactive-MS

As one of the most widely abused designer benzodiazepines in the world, etizolam has been found in many cases in many countries. In this study, UPLC-Q-Exactive-MS was used for the first time to establish a dynamic change model of etizolam and its metabolites in rats. Compared with previous studies, the detection sensitivity and reproducibility of the instrument were higher. In the experiment, we optimized the traditional pharmacokinetic model based on Gauss function. According to the significant difference of etizolam in the plasma elimination phase of rats, a new pharmacokinetic model based on Lorentz function was established to describe the dynamic changes of etizolam more rigorously, which made the error effects lower and the accuracy of the pharmacokinetic parameters was improved. At the same time, the pharmacokinetic parameters of etizolam were compared with four other designer benzodiazepines reported in previous studies in rats, and we found the direct reason for the popularity of etizolam in the NPS market and explored the future development of etizolam for the first time. In addition, 21 metabolites were found through rat experiments to effectively detect etizolam abuse for a long time, of which 4 metabolites had the longest detection window and could be used as long-acting metabolites for experiments, which greatly prolongs the detection window and extends the time range in which etizolam was detected in real cases. This study is the first to conduct a systematic and comprehensive study on the metabolism and pharmacokinetics of etizolam and find out the direct reason for the prevalence of etizolam abuse, and we also discuss the development trend of etizolam in the future market of new psychoactive substances, which is beneficial for forensic experts to assess the trend of drug abuse and can provide reference for relevant drug control and drug treatment.

Fentanyl concentrations in ligated femoral blood in the presence and absence of NPS benzodiazepine drugs. A review of over 1250 benzo-dope / fentanyl toxicity cases in Alberta, Canada

The drug combination referred to as 'benzo dope' has become prevalent in recent years, with an increasing number of fentanyl-related deaths reporting the concomitant presence of one or more benzodiazepine drug, such as etizolam, flualprazolam and flubromazepam. The central nervous system (CNS) depressant effects of these benzodiazepine drugs can exacerbate respiratory and CNS depressant effects resulting from the use/misuse of potent opioids such as fentanyl. This combined and enhanced drug-induced toxicity can pose a significant threat to life. Over a three-year period (2020-2022), the Office of the Chief Medical Examiner, Edmonton, Alberta, Canada issued 2812 case reports with fentanyl detected; of these cases, approximately 45% (1261) were positive for at least one benzodiazepine drug. This study presents concentrations of both fentanyl and benzodiazepine drugs in post mortem blood collected from a visualized, ligated femoral vein. The study demonstrates that the blood concentration of fentanyl in benzo-dope case reports is considerably higher than in cases where no benzodiazepine drug was detected.The median concentration of fentanyl in femoral blood for cases that also contained a benzodiazepine drug was 12.4 ng/mL (2020), 11.9 ng/mL (2021) and 14.0 ng/mL (2022). The median concentration of fentanyl in femoral blood for cases that did not contain a benzodiazepine drug was 8.5 ng/mL (2020), 7.0 ng/mL (2021) and 7.2 ng/mL (2022). The percent differences between the groups were similar with those observed from quantitative analysis of drug powders from unrelated police seizures in Alberta, Canada, suggesting the observed differences in blood fentanyl concentration may be due to the use of a drug substance with a higher concentration of fentanyl.Furthermore, the reported concentration of the benzodiazepine drug(s) is low, such that the role/contribution, if any, that this drug may have played in the decedents' death should be questioned and carefully considered by the certifying medical examiner/coroner.

Metabolic Profile Analysis of Designer Benzodiazepine Etizolam in Zebrafish and Human Liver Microsomes

As one of the most widely abused designer benzodiazepines worldwide, Etizolam is characterized by its high addiction potential, low production cost, and difficulty in detection. Due to the rapid metabolism of Etizolam in the human body, the probability of detecting the Etizolam parent drug in actual case samples by forensic personnel is low. Therefore, without detecting the parent drug, analysis of Etizolam metabolites can help forensic personnel provide references and suggestions on whether the suspect has taken Etizolam. This study simulates the objective metabolic process of the human body. It establishes a zebrafish in vivo metabolism model and a human liver microsome in vitro metabolism model to analyze the metabolic characteristics of Etizolam. A total of 28 metabolites were detected in the experiment, including 13 produced in zebrafish, 28 produced in zebrafish urine and feces, and 17 produced in human liver microsomes. The UPLC-Q-Exactive-MS technology was used to analyze the structures and related metabolic pathways of Etizolam metabolites in zebrafish and human liver microsomes, and a total of 9 metabolic pathways were identified, including monohydroxylation, dihydroxylation, hydration, desaturation, methylation, oxidative deamination to alcohol, oxidation, reduction acetylation, and glucuronidation. Among them, metabolites involving hydroxylation reactions (including monohydroxylation and dihydroxylation) accounted for 57.1% of the total number of potential metabolites, indicating that hydroxylation may be the major metabolic pathway of Etizolam. Based on the response values of each metabolite, monohydroxylation (M1), desaturation (M19), and hydration (M16) were recommended as potential biomarkers for Etizolam metabolism. The experimental results provide reference and guidance for forensic personnel in identifying Etizolam use in suspects.

Variability in the unregulated opioid market in the context of extreme rates of overdose

BACKGROUND

Drug checking uses analytical chemistry technologies to report on the composition of drugs from the unregulated market to reduce substance use-related risks, while additionally allowing for monitoring and reporting of the supply. In the context of an overdose crisis linked to fentanyl, we used drug checking data to examine variability within the illicit opioid supply.

METHODS

In this time-series analysis, data was collected from a drug checking service in Victoria, Canada from November 2020 to July 2021. Drugs reported as opioids by participants of the service (N = 454) were analyzed to determine sample composition and paper spray mass spectroscopy was used to quantify low-concentration actives. Interquartile and statistical process control (SPC) analysis, namely standard deviation control charts, were used to examine the degree of variability among samples.

RESULTS

Fentanyl was found in 96% of samples reported to be opioids, with a median concentration of 9%. Concentrations varied significantly, with a standard deviation of 7% for fentanyl and where nearly 20% of data points fell outside the control limits. Over half of the samples contained an additional and unexpected active, most commonly etizolam (43% of samples). Etizolam also showed a large level of variability, uncorrelated to that of fentanyl.

CONCLUSIONS

Based on our chemical quantification and SPC analysis, a high degree of variability was found in opioid samples from the unregulated market in both the drugs detected and the concentrations of those drugs. This demonstrated the opioid crisis to be less attributable to a bad batch of drugs but rather the general variability found in the unregulated market.

Rapid and accurate etizolam detection using surface-enhanced Raman spectroscopy for community drug checking

BACKGROUND

In British Columbia, Canada, illicit opioids have been increasingly combined with etizolam, a benzodiazepine analog, that continues to challenge popular portable drug checking technologies as it is often present in low concentrations as a result of its high potency. An unknown combination of opioids and benzodiazepines may have dangerous consequences due to unpredictable dosing, increased respiratory depression, and complicated overdose response measures.

METHODS

Surface-enhanced Raman spectroscopy (SERS) using a portable Raman spectrometer is used to establish a univariate model for the detection of etizolam in opioid drug mixtures (n=100) obtained from the Vancouver Island Drug Checking Project, where the presence of etizolam has been determined using paper-spray mass spectrometry. Benzodiazepine immunoassay test strips are also performed on all samples for comparison.

RESULTS

SERS is shown to detect etizolam with high sensitivity (96%) and specificity (86%). In contrast, benzodiazepine test strips demonstrate a low sensitivity (8%) for the detection of etizolam of the same samples (n=100), with only small improvements when studied over a larger subset of samples (n=506, sensitivity = 29%).

CONCLUSION

We have demonstrated the potential of SERS for trace detection of etizolam within complex sample matrices. Since SERS is one of the few portable technologies capable of trace detection, further studies on its ability for quantification and discrimination of trace adulterants in street samples is of significant interest for point-of-care applications.

Diverse psychotropic substances detected in drug and drug administration equipment samples submitted to drug checking services in Toronto, Ontario, Canada, October 2019-April 2020

BACKGROUND

The overdose crisis has generated innovative harm reduction and drug market monitoring strategies. In Toronto, Ontario, Canada, a multi-site drug checking service (DCS) pilot project was launched in October 2019. The project provides people who use drugs with information on the chemical composition of their substances, thereby increasing their capacity to make more informed decisions about their drug use and avoid overdose. DCS also provides real-time market monitoring to identify trends in the unregulated drug supply.

METHODS

Sample data were obtained through analyses of drug and used drug administration equipment samples submitted anonymously and free of charge to DCS in downtown Toronto from October 10, 2019, to April 9, 2020, representing the first six months of DCS implementation. Analyses were conducted in clinical laboratories using liquid chromatography- and/or gas chromatography-mass spectrometry (LC-MS, GC-MS) techniques.

RESULTS

Overall, 555 samples were submitted, with 49% (271) of samples that were found to contain high-potency opioids, of which 87% (235) also contained stimulants. Benzodiazepine-type drugs were found in 21% (116) of all samples, and synthetic cannabinoids in 1% (7) of all samples. Negative effects (including overdose, adverse health events, and extreme sedation) were reported for 11% (59) of samples submitted for analysis.

CONCLUSIONS

Toronto's DCS identified a range of high-potency opioids with stimulants, benzodiazepine-type drugs, and a synthetic cannabinoid, AMB-FUBINACA. This information can inform a range of evidence-informed overdose prevention efforts.

Characteristics of fatal 'novel' benzodiazepine toxicity in Australia

INTRODUCTION

The study aimed to determine: 1. The characteristics of all recorded cases of fatal drug poisoning involving 'novel' benzodiazepines (NBZDs) in Australia; 2. The toxicology of cases; and 3. The major autopsy findings.

METHODS

Retrospective study of all deaths due to drug toxicity in Australia in which NBZDs were present in blood toxicology, retrieved from the National Coronial Information System (2000-2021). Information was collected on case characteristics, toxicology and major organ pathology.

RESULTS

A total of 40 cases were identified, the first occurring in 2015, with a median age of 26.5 years and 87.5% being male. Death was due to accidental toxicity in 92.5% of cases. There were extensive histories of substance use problems (80.0%) and mental health problems (32.5%). Etizolam was the most common NBZD (87.5%), followed by flubromazolam (15.0%), with other NBZDs detected in 20.0% (delorazepam, diclazepam, flualprazolam, flubromazepam, lormetazepam). Multiple NBZDs were present in 27.5%. Other drugs were present in 97.5%, most commonly opioids (70.0%), registered benzodiazepines (62.5%), psychostimulants (45.0%) and gabapentinoids (32.5%). A CNS depressant other than a NBZD was detected in 95.0% (n = 38). Autopsies were conducted and available for 30 cases, with pulmonary oedema (76.7%, n = 23), aspiration of vomitus (46.7%, n = 14) and acute bronchopneumonia (36.7%, n = 11) the most common diagnoses.

CONCLUSIONS

The 'typical' NBZD-related death was a young male who died due to accidental toxicity. Deaths most frequently involved etizolam and multiple substances, particularly depressants.

From the clinic to the street: the changing role of benzodiazepines in the Scottish overdose epidemic

Drug-related deaths in Scotland increased for seven years in a row between 2014 and 2020 consolidating Scotland's place at the top of the United Kingdom and European drug-related mortality charts. One of the defining features of this recent and rapid rise has been the role of benzodiazepines which are now involved in two-thirds of all cases. Policy decisions over four decades have contributed to the supply and demand drivers of this unique element of the Scottish overdose crisis. An illicit market once populated by diverted prescription medications is now dominated by a toxic supply of NPS-type benzodiazepines or so-called 'street benzos' which have increased the risk environment for people who use drugs. In response, Scotland needs to urgently expand its harm reduction infrastructure and implement safer supply, drug testing and drug consumption rooms. Such a response should be made in parallel to addressing the socioeconomic inequalities which are fuelling an epidemic of global significance.

Portable gas chromatography-mass spectrometry in drug checking: Detection of carfentanil and etizolam in expected opioid samples

BACKGROUND

There has been a recent increase in adulteration of opioids with low concentration actives such as fentanyl analogues and benzodiazepines. As drug checking projects using vibrational spectroscopy continue to seek confirmatory lab-based testing, the concern and reality of missing these potentially harmful substances in point-of-care testing is prevalent.

METHODS

A portable GC-MS was used to analyze select opioid samples acquired at a drug checking service in Victoria, Canada (n=59). Certified reference standards of several fentanyl analogues and benzodiazepines were measured to guide targeted analysis of these samples. Results were compared with those obtained using a lab-based paper spray mass spectrometer.

RESULTS

Portable GC-MS was able to identify 62% of samples containing carfentanil and 36% of samples containing etizolam. In the case of etizolam, the success rate was higher for more potent samples: 78% of etizolam-containing samples were identified when the etizolam concentration was above 3% by weight. In comparison, infrared spectroscopy was able to detect etizolam in only 9% of the etizolam-containing samples, and is not sensitive enough to detect carfentanil at relevant concentrations.

CONCLUSIONS

Portable GC-MS has potential in identifying low concentration substances in a point-of-care setting, without relying on subsequent off-site confirmatory testing.

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.

Femoral blood concentrations of the designer benzodiazepine etizolam in post-mortem cases

Etizolam is a thienodiazepine that although licensed for clinical usage in Japan, India and South Korea is commonly abused and detected in post-mortem cases around the world. To date, there are limited data in the literature to allow for the interpretation of blood concentrations of etizolam in post-mortem cases. A liquid chromatography with tandem mass spectrometry method was used to quantitate etizolam concentrations in 28 post-mortem cases where etizolam was detected. The median concentration of etizolam in femoral blood was 8.5 ng/mL (range 1.0-172.0 ng/mL; n = 24); in antemortem plasma, the etizolam concentration range was 4-44 ng/mL (n = 4). The mean age of the individuals abusing etizolam was 38.5 ± 8.4 years (median 39 years), with the majority being male (86%). In all of the cases, multiple drugs were detected, with the most common being pregabalin (61%) followed by morphine/heroin (54%), diazepam (54%) and benzoylecgonine (21%), illustrating the increasing problem of poly-substance use in drug abusers. The cause of death in the cases in which etizolam was detected was multi-drug toxicity in 87.5% of the cases, with 12.5% unrelated to drug use (hangings and blunt-force trauma). These data will further help forensic practitioners with the interpretation of post-mortem etizolam concentrations.

An outbreak of novel psychoactive substance benzodiazepines in the unregulated drug supply: Preliminary results from a community drug checking program using point-of-care and confirmatory methods

BACKGROUND

From mid-2018, an increase in novel psychoactive substance (NPS) benzodiazepines was noted on surveillance of the unregulated drug market around Vancouver, British Columbia, Canada. The rise was concordant with an outbreak of atypical overdoses suspicious for benzodiazepine adulteration of unregulated opioids. This study sought to describe the number and type of NPS benzodiazepines in a sample drawn from a community drug checking program during this period, and to explore accuracy of point-of-care drug checking technologies when compared to confirmatory methods in this sample.

METHODS

Point-of-care drug checking data using fentanyl and benzodiazepine test strips as well as Fourier transform infrared spectroscopy were gathered at harm reduction sites in the Vancouver area from October 2018 to January 2020. A convenience subsample underwent confirmatory testing with gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, or quantitative nuclear magnetic resonance spectroscopy.

RESULTS

Of 159 samples with both point-of-care and confirmatory results, 24 (15.1%) contained at least one NPS benzodiazepine, including etizolam (n = 18), flubromazolam (n = 3), flualprazolam (4), and flubromazepam (n = 1). Of 114 confirmatory samples expected by participants on self-report to contain opioids, 18 (15.8%) contained some NPS benzodiazepine, with 16 (14.0%) containing both an NPS benzodiazepine and an opioid, always fentanyl. False positive and negative rates were 15.5% and 37.5% for test strips, and 3.9% and 91.7% for FTIR, respectively. Combined together, false positive and negative rates of point-of-care methods were 17.8% and 29.2%.

CONCLUSIONS

NPS benzodiazepine adulteration in an unregulated drug supply sample reveals new risks compounding ongoing harms associated with the synthetic opioid epidemic. Given substantial false positive and false negative rates noted in our sample for point-of-care detection methods, cautious use of combined point-of-care methods, routinely paired with confirmatory drug checking may aid in early detection and monitoring of unregulated drug markets and inform targeted harm reduction strategies and health policy approaches.

Drug checking identifies counterfeit alprazolam tablets

BACKGROUND

Non-prescribed benzodiazepine use is increasing in North America, especially among youth. Owing to increasing demand, counterfeit benzodiazepine tablets are mass-produced in clandestine, unregulated environments and sold as legitimate pharmaceuticals. This study aimed to examine the contents of counterfeit alprazolam tablets available in the unregulated drug market in British Columbia, Canada.

METHODS

Data were collected from an ongoing evaluation of a community drug checking service in British Columbia between October 2017 and March 2020. The service operates point-of-care in harm reduction sites using Fourier-transform infrared (FTIR) spectrometers coupled with fentanyl and benzodiazepine immunoassay strips. A subset of samples were sent for confirmatory analysis at partner laboratories and underwent one or more of gas chromatography/mass spectrometry, liquid chromatography/mass spectrometry, and quantitative nuclear magnetic resonance analysis.

RESULTS

During the study period, 10,814 total samples were submitted for drug checking, 139 of which were expected to be Xanax (alprazolam) or generic tablets and met the criteria for inclusion. Using FTIR analysis, 33 (23.7 %) samples were identified to contain alprazolam. Only 122 samples were checked using benzodiazepine immunoassay strips and 88 (72.1 %) tested positive. Qualitative results from the 20 samples submitted for confirmatory analysis included various new psychoactive substances and only 2 contained only alprazolam.

CONCLUSIONS

Our findings provide evidence that Xanax tablets obtained from the unregulated drug market are likely to be counterfeit and may not contain alprazolam. Drug checking offers people who use drugs a valuable means to determine the contents of their substances; however, limitations of point-of-care technologies must be considered.

The adulterated XANAX pill: a fatal intoxication with etizolam and caffeine

A 49-year old man was found dead at home next to a glass containing a dried, white, crystalline substance and near a bag containing pills with the imprint XANAX, the trade name of alprazolam. A comprehensive screening of material collected during the autopsy revealed the presence of etizolam and caffeine in lethal concentrations (0.77 μg/mL and 190 μg/mL) but no trace of alprazolam. Benzodiazepine analogue etizolam is rarely prescribed in Germany, and as a result there are not many reports about fatal cases. It has anxiolytic, hypnotic, sedative and muscle-relaxant properties and is used for the short-term treatment of anxiety and panic attacks. The purine alkaloid caffeine, conversely, is the most widely used central nervous system stimulant. The following report outlines potentially the first reported case of a lethal combination of the downer etizolam and the upper caffeine in medical literature.

Is etizolam a safe medication? Effects on psychomotor perfomance at therapeutic dosages of a newly abused psychoactive substance

Etizolam is a drug from the thienotriazoldiazepine class, widely prescribed as anxiolytic due to its apparently secure toxicological profile. Nevertheless, some recent cases of etizolam dependence, intoxications and fatalities associated to its abuse have been reported in the international literature. For this reason, the drug listed as new psychoactive substance (NPS) by the World Health Organization (WHO) since 2015. Euphoric effect at high dosage is the first cause of its recreational use that has determined a wider distribution in the illicit market. An experimental study was performed to obtain evidence that etizolam at low therapeutic dosages is a drug with negligible influence on the psychomotor performances involved in driving. The psychomotor performance was assessed by performing different tests, such as critical tracking task (CTT), critical flicker fusion (CFF), choice reaction time (CRT), visual vigilance task (VVT), response competition test (RCT) in a group of 16 healthy volunteers after a single administration of etizolam at two different dosages (0.25 mg or 1.00 mg) in comparison to placebo. The test results showed that etizolam at 0.25 mg and 1.00 mg had no significant effect on vigilance, short term memory, psychomotor coordination or speed in decision making. Differently, abuse of etizolam to obtain the euphoric effects at presumably high dosages or in combination with other psychoactive substances could be fatal. The negligible side effects on mental and behavioral function demonstrated by this study, could represent an incitement to abuse, which can be strongly discouraged with correct information on differences between its correct use and its misuse.

Etizolam attenuates the reduction in cutaneous temperature induced in mice by exposure to synthetic predator odor

Anxiety- and stress-related disorders can be debilitating psychiatric conditions in humans. To prevent or ameliorate these conditions, reliable animal models are needed to evaluate the effects of anxiolytic drugs. Previously, we found that a mixture of three pyrazine analogues (P-mix) that were present at high levels in wolf urine induced fear-related responses in mice, rats and deer. A change in cutaneous temperature was shown to be induced by acute stress simultaneously with changes in heart rate, arterial pressure and freezing behavior, raising the possibility that cutaneous temperature could be used as an index of stress. In the present study, using infrared thermography, we showed that exposure of mice to P-mix induced a decrease in cutaneous temperature. We then examined the dose-dependent effects of an anxiolytic drug, etizolam (0-20 mg/kg), on the temperature decrease. Pre-administration of etizolam (5 mg/kg or higher) inhibited the P-mix-induced decrease in cutaneous temperature. Exposure to P-mix induced Fos-immunoreactivity, a marker of neuronal excitation, at the mouse amygdala and hypothalamus, and etizolam (5 mg/kg) attenuated that immunoreactivity. The present results suggested that the measurement of cutaneous P-mix-induced temperature changes in mice could be used as an animal model for evaluating the effects of anxiolytic drugs.