Fentanyls continue to replace heroin in the drug arena: the cases of ocfentanil and carfentanil

Strategies for developing μ opioid receptor agonists with reduced adverse effects

Opioids are currently the most effective and widely used painkillers in the world. Unfortunately, the clinical use of opioid analgesics is limited by serious adverse effects. Many researchers have been working on designing and optimizing structures in search of novel μ opioid receptor(MOR) agonists with improved analgesic activity and reduced incidence of adverse effects. There are many strategies to develop MOR drugs, mainly focusing on new low efficacy agonists (potentially G protein biased agonists), MOR agonists acting on different Gα subtype, targeting opioid receptors in the periphery, acting on multiple opioid receptor, and targeting allosteric sites of opioid receptors, and others. This review summarizes the design methods, clinical applications, and structure-activity relationships of small-molecule agonists for MOR based on these different design strategies, providing ideas for the development of safer novel opioid ligands with therapeutic potential.

Trace Detection of Adulterants in Illicit Opioid Samples Using Surface-Enhanced Raman Scattering and Random Forest Classification

The detection of trace adulterants in opioid samples is an important aspect of drug checking, a harm reduction measure that is required as a result of the variability and unpredictability of the illicit drug supply. While many analytical methods are suitable for such analysis, community-based approaches require techniques that are amenable to point-of-care applications with minimal sample preparation and automated analysis. We demonstrate that surface-enhanced Raman spectroscopy (SERS), combined with a random forest classifier, is able to detect the presence of two common sedatives, bromazolam (0.32-36% w/w) and xylazine (0.15-15% w/w), found in street opioid samples collected as a part of a community drug checking service. The Raman predictions, benchmarked against mass spectrometry results, exhibited high specificity (88% for bromazolam, 96% for xylazine) and sensitivity (88% for bromazolam, 92% for xylazine) for the compounds of interest. We additionally provide evidence that this exceeds the performance of a more conventional approach using infrared spectral data acquired on the same samples. This demonstrates the feasibility of SERS for point-of-care analysis of challenging multicomponent samples containing trace adulterants.

Fentanyl and its derivatives: Pain-killers or man-killers?

Fentanyl is a synthetic μ-opioid receptor agonist approved to treat severe to moderate pain with faster onset of action and about 100 times more potent than morphine. Over last two decades, abuse of fentanyl and its derivatives has an increased trend, globally. Currently, the United States (US) faces the most serious situation related to fentanyl overdose, commonly referred to as the opioid epidemic. Nowadays, fentanyl is considered as the number one cause of death for adults aged 18-45 in the US. Synthesis and derivatization of fentanyl is inexpensive to manufacture and easily achievable. Indeed, more than 1400 fentanyl derivatives have been described in the scientific literature and patents. In addition, accessibility and efficacy of fentanyl and its derivatives can play a potential role in misuse of these compounds as a chemical weapon. In this review, the properties, general pharmacology, and overdose death cases associated with fentanyl and selected derivatives are presented. Moreover, current opioid epidemic in the US, Moscow theatre hostage crisis, and potential misuse of fentanyl and its derivatives as a chemical weapon are disclosed.

Pharmacokinetic Properties of an FDA-approved Intranasal Nalmefene Formulation for the Treatment of Opioid Overdose

Nalmefene is a high-affinity, long-duration opioid antagonist that was approved in 1995 as an injection for the treatment of opiate overdose, but subsequently withdrawn (2008) for reasons other than safety or effectiveness. The dramatic rise in opioid overdose deaths over the past 7-8 years catalyzed the development of an intranasal (IN) formulation of nalmefene for the emergency treatment of opioid overdose. The studies described here compare the pharmacokinetic properties and safety profiles of an IN formulation containing nalmefene (2.7 mg in 0.1 mL) to an approved 1 mg intramuscular (IM) dose. IN nalmefene produced maximum plasma concentrations that were significantly higher than observed following the IM dose (12.2 and 1.77 ng/mL, respectively). The time to reach maximum plasma concentrations was also faster following IN administration (0.25 and 0.33 hours, respectively) with significant differences in plasma concentrations manifested as early as 2.5 minutes after administration (NCT04759768). The plasma half-life of nalmefene was similar following IM and IN administration (10.6-11.4 hours). Furthermore, dose-normalized nalmefene exposure was similar for both 1 spray in each nostril and 2 sprays in the same nostril compared to a single spray in each nostril (NCT05219669). There were no sex differences in the pharmacokinetic properties of either IN or IM nalmefene. In an era when almost 90% of opioid overdose deaths have been linked to high-potency synthetic opioids, the ability to rapidly deliver high concentrations of nalmefene could represent an important tool for reducing both morbidity and mortality.

Socioeconomic and psychosocial determinants of substance misuse - a national perspective

Accurate estimates of population drug use and an understanding of the factors that influence substance choice are essential for the development of appropriate and targeted prevention strategies and campaigns. This review aims to provide an overview of the socioeconomic and psychosocial factors that influence substance use patterns within the Australian population through exploration of current and historical examples of substance misuse. Australia's comparatively large online drug market is reflective of the country's relative geographic isolation and high local drug prices. Legislation, particularly relating to cannabis cultivation and personal use, has evolved significantly in response to increased scientific and commercial applications and changing attitudes towards medical and personal use. Methylamphetamine use is disproportionately high, attributed to Australia's geographic location, high rates of local manufacture, steady cost, and increased purity. Despite the increased cost of cocaine over time, the profile of users appears to dictate rates of use. The prevalence of injecting drug use is driven by a lack of education, perceived risk, stigma, and other social factors. Additionally, psychosocial factors also contribute to substance misuse among specific population subgroups such as petrol sniffing among Indigenous Australians. Understanding the reasons for geographical variability in illicit drug use assists in the interpretation of substance-associated behavior in specific groups/populations and in guiding future intervention efforts and predictions of emerging trends. In addition, an understanding of factors influencing local drug usage may assist forensic practitioners in evaluating the occurrence and effects of particular substances that may emerge as significant factors in drug-related deaths.

Development of a neural network model to predict the presence of fentanyl in community drug samples

INTRODUCTION

Increasingly, Fourier-transform infrared (FTIR) spectroscopy is being used as a harm reduction tool to provide people who use drugs real-time information about the contents of their substances. However, FTIR spectroscopy has been shown to have a high detection limit for fentanyl and interpretation of results by a technician can be subjective. This poses concern, given that some synthetic opioids can produce serious toxicity at sub-detectable levels. The objective of this study was to develop a neural network model to identify fentanyl and related analogues more accurately in drug samples compared to traditional analysis by technicians.

METHODS

Data were drawn from samples analyzed point-of-care using combination FTIR spectroscopy and fentanyl immunoassay strips in British Columbia between August 2018 and January 2021. We developed neural network models to predict the presence of fentanyl based on FTIR data. The final model was validated against the results from immunoassay strips. Prediction performance was assessed using F1 score, accuracy, and area under the receiver-operating characteristic curve (AUROC), and was compared to results obtained from analysis by technicians.

RESULTS

A total of 12,684 samples were included. The neural network model outperformed results from those analyzed by technicians, with an F1 score of 96.4% and an accuracy of 96.4%, compared to 78.4% and 82.4% with a technician, respectively. The AUROC of the model was 99.0%. Fentanyl positive samples correctly detected by the model but not by the technician were typically those with low fentanyl concentrations (median: 2.3% quantity by weight; quartile 1-3: 0.0%-4.6%).

DISCUSSION

Neural network models can accurately predict the presence of fentanyl and related analogues using FTIR data, including samples with low fentanyl concentrations. Integrating this tool within drug checking services utilizing FTIR spectroscopy has the potential to improve decision making to reduce the risk of overdose and other negative health outcomes.

A pharmacologically pre-contracted smooth muscle bowel model for the study of highly-potent opioid receptor agonists and antagonists

Isolated organ models are a versatile tool for pharmacological and toxicological research. Small bowel has been used to assess the inhibition of smooth muscle contraction by opioids. In the present study, we set out to establish a pharmacologically stimulated rat bowel model. The effects of carfentanil, remifentanil and the new synthetic opioid U-48800 and their respective antagonists naloxone, nalmefene and naltrexone were studied in a small bowel model in rats. The IC₅₀ values of the tested opioids were as follows: carfentanil (IC₅₀ = 0.02 µmol/L, CI 0.02-0.03 µmol/L) ≫ remifentanil (IC₅₀ = 0.51 µmol/L, CI 0.40-0.66 µmol/L) ≫ U-48800 (IC₅₀ = 1.36 µmol/L, CI 1.20-1.54 µmol/L). The administration of the opioid receptor antagonists naloxone, naltrexone and nalmefene led to progressive, parallel rightward shifts of the dose-response curves. Naltrexone was most potent in antagonizing the effects of U-48800, whereas naltrexone and nalmefene were most effective in antagonizing the effects of carfentanil. In summary, the current model seems to be a robust tool to study opioid effects in a small bowel model without the necessity of using electrical stimulation.

Quantitative Raman Cross-Sections and Band Assignments for Fentanyl and Fentanyl Analogs

Raman cross sections and spectra were measured for five synthetic opioid fentanyl analogs: fentanyl citrate, sufentanil citrate, alfentanil HCl, carfentanil oxalate, and remifentanil HCl. The measurements were performed with excitation wavelengths in the visible (532 nm) and near infrared (785 nm). In addition, density functional theory (DFT) calculations were employed to generate simulated spectra of the compounds and aid in identification of the observed spectral modes. These cross-section measurements and calculations were also used to assess results from a series of measurements of fentanyls cut with other powdered materials. These measurements are valuable for assessment of field-deployable Raman chemical sensors for detection of fentanyl and fentanyl analogs, including when mixed with other materials.

Structure-Kinetics Relationships of Opioids from Metadynamics and Machine Learning Analysis

The nation's opioid overdose deaths reached an all-time high in 2021. The majority of deaths are due to synthetic opioids represented by fentanyl. Naloxone, which is a FDA-approved reversal agent, antagonizes opioids through competitive binding at the μ-opioid receptor (mOR). Thus, knowledge of the opioid's residence time is important for assessing the effectiveness of naloxone. Here, we estimated the residence times (τ) of 15 fentanyl and 4 morphine analogs using metadynamics and compared them with the most recent measurement of the opioid kinetic, dissociation, and naloxone inhibitory constants (Mann et al. Clin. Pharmacol. Therapeut. 2022, 120, 1020-1232). Importantly, the microscopic simulations offered a glimpse at the common binding mechanism and molecular determinants of dissociation kinetics for fentanyl analogs. The insights inspired us to develop a machine learning approach to analyze the kinetic impact of fentanyl's substituents based on the interactions with mOR residues. This proof-of-concept approach is general; for example, it may be used to tune ligand residence times in computer-aided drug discovery.

Toxicity and behavioural effects of ocfentanil and 2-furanylfentanyl in zebrafish larvae and mice

The introduction of the so-called New Psychoactive Substances represents a problem of global concern due to several factors, including multiplicity of structures, poorly known activity, short half-life in the market, lack of pure standards etc. Among these problems, of the highest relevance is also the lack of information about metabolism and adverse effects, which must be faced using simple and low-cost animal models. On these grounds, the present work has been carried out on 5 days post fertilization zebrafish (Danio rerio) larvae in comparison with adult mice (Mus musculus). Ocfentanil and 2-furanylfentanyl were administered at different concentrations to zebrafish larvae (1, 10 µM) and mice (0.1, 1, 6, 15 mg/kg). The behavioural assay showed a decrease in basal locomotor activity in zebrafish, whereas in mice this effect was evident only after the mechanical stimulus. Larva extracts and mice urine were analysed by using liquid chromatography coupled to high resolution mass spectrometry to identify the metabolic pathways of the fentanyl analogs. For 2-furanylfentanyl, the most common biotransformations observed were hydroxylation, hydration and oxidation in zebrafish larvae, whereas mice produced mainly the dihydrodiol metabolite. Hydroxylation was the major route of metabolism for ocfentanil in zebrafish larvae, while in mice the O-demethylated derivative was the main metabolite. In addition, a study was conducted to evaluate morphological effects of the two drugs on zebrafish larvae. Malformations were noticeable only at the highest concentration of 2-furanylfentanyl, whereas no significant damage was observed with ocfentanil. In conclusion, the two animal models show similarities in behavioral response and in metabolism, considering the different biological investigated.

Surface-enhanced Raman spectroscopy for detection of fentanyl and its analogs by using Ag-Au nanoparticles

The problem of opioid abuse has become a global problem. Thus, creating an urgent need for highly sensitive detection of opioid substances. In this work, we developed a method for the controllable preparation of Ag@Au nanocrystals (Ag@Au NCs) for highly sensitive SERS detection of fentanyl and its analogs. By regulating the concentration of ligands on the surface of silver seed, we successfully prepared Ag@Au NCs with three different morphologies, including core-satellite, yolk shell and hollow structure. Firstly, we explored the SERS-enhancing effect of Ag@Au NCs with different morphology using rhodamine 6G as the molecule to be tested. The results show that the core-satellite Ag@Au NCs has the best SERS effect, and the lowest detection concentration for R6G reached to 10^-10 M. Furthermore, we used the prepared core-satellite Ag@Au NCs to detect fentanyl and its five analogs, including carfentanyl, furanylfentanyl, thiofentanyl, 4-fluorobutyrfentanyl and N-4-piperidylacetanilide. Trace detection was achieved for the above six substances. For the environmental water samples spiked with fentanyl, the calculated recovery was 89.2% with an RSD value of 7.3%. Moreover, in order to realize the qualitative analysis of the characteristic peaks of different fentanyl analogs, we performed DFT calculations on the Raman spectra of the above-mentioned 6 substances. By analyzing the DFT calculation results, conventional Raman spectroscopy and SERS spectroscopy, we realized the distinction of six fentanyl analogs with similar structures.

Student pharmacists' attitudes, perceptions, and knowledge regarding opioid use, misuse, and overdose: Four years of data

INTRODUCTION

The American Association of Colleges of Pharmacy has urged pharmacy faculty to commit to actions to reduce the public health threat from opioid use and misuse. Optimizing student pharmacist training necessitates understanding changes in their attitudes and perceptions over time. This study assessed student attitudes, perceptions, and understanding of addiction, opioid use and misuse, and opioid overdose over four sequential years, from 2016 to 2019.

METHODS

The participants were third-professional year doctor of pharmacy students enrolled in a required course. Participants voluntarily completed a 27-statement survey to determine student attitudes, perceptions, and understanding.

RESULTS

A total of 452 participants completed the survey (response rate = 76.5%). Of the 27 survey items, five survey statements showed year on year positive increases in specific student attitudes towards addiction, hopefulness for its treatment, and confidence to use and train opioid overdose reversal agents. These yearly changes did not appear to be related to any changes in the academic aptitude of the students. The 22 remaining statements showed positive and stable attitudes towards self-perceived understanding of opioid use and misuse, hopefulness for its treatment, and the role of pharmacists.

CONCLUSION

To our knowledge, this is the first large multiyear assessment of student pharmacists' attitudes, perceptions, and understanding of opioid use, misuse, and overdose. The data indicate favorable and improving attitudes. Knowledge of student attitudes, perceptions, and understanding regarding opioid use, misuse, and overdose will aid in the development of effective training programs for students in our, and other colleges of pharmacy.

Determination of Nine Fentanyl Drugs in Hair Samples by GC-MS/MS and LC-MS/MS

We established GC-MS/MS and LC-MS/MS analysis methods for nine fentanyl drugs in hair samples. Human hairs were prepared by soaking in a solution of water-dimethyl sulfoxide with target analytes. The drugs were norfentanyl, acetyl fentanyl, para-fluorofentanyl, isobutyryl fentanyl, fentanyl, thiofentanyl, 4-fluoroisobutyr fentanyl, ocfentanil, and tetrahydrofuran fentanyl. For a single-factor experiment, a Box-Behnken design-response surface was used to optimize the pretreatment conditions of samples. The prepared samples were quantitatively analyzed by GC-MS/MS and LC-MS/MS. The working curve method was used for quantitative analysis with fentanyl-D5 as the internal standard. The concentrations of the nine fentanyl drugs in the samples were 1.488-6.494 ng mg^-1, RSDs < 5.0%. For GC-MS/MS, the linear range of the nine fentanyl drugs was 0.5-5.0 ng mg^-1, r ² > 0.999. The detection limits were 0.02-0.05 ng mg^-1, and the recovery rates were >86%. For LC-MS/MS, the nine fentanyl drugs had an excellent linear relationship within the concentration range of 3.0-220.0 pg mg^-1, r ² > 0.999. The detection limits were 0.05 pg mg^-1 and the recovery rates were >84%. The established methods were used for the detection of fentanyl drugs in human hairs, with high sensitivity, accuracy, and specificity. These two methods can be used for the certification of fentanyl certified reference substances (CRMs). In the experiment, the developed hair CRMs, which will continue to be studied in the future, are expected to be used in forensic drug abuse detection.

Measuring treatment attrition at various stages of engagement in Opioid Agonist Treatment in Ontario Canada using a cascade of care framework

Background

The cascade of care framework is an effective way to measure attrition at various stages of engagement in Opioid Agonist Treatment (OAT). The primary objective of the study was to describe the cascade of care for patients who have accessed OAT from a network of specialized addiction clinics in Ontario, Canada. The secondary objectives were to evaluate correlates associated with retention in OAT at various stages and the impact of patients’ location of the residence on retention in OAT.

Design

A multi-clinic retrospective cohort study was conducted using electronic medical record (EMR) data from the largest network of OAT clinics in Canada (70 clinics) from 2014 to 2020. Study participants included all patients who received OAT from the network of clinics during the study period.

Measurements

In this study, four stages of the cascade of care framework were operationalized to identify treatment engagement patterns, including patients retained within 90 days, 90 to 365 days, one to 2 years, and more than 2 years. Correlates associated with OAT retention for 90 days, 90 to 365 days, 1 to 2 years, and more than 2 years were also evaluated and compared across rural and urban areas in northern and southern Ontario.

Results

A total of 32,487 patients were included in the study. Compared to patients who were retained in OAT for 90 days, patients who were retained for 90 to 365 days, 1 to 2 years, or more than 2 years were more likely to have a higher number of treatment attempts, a higher number of average monthly urine drug screening and a lower proportion of positive urine drug screening results for other drug use.

Conclusion

Distinct sociodemographic and clinical factors are likely to influence treatment retention at various stages of engagement along the OAT continuum. Research is required to determine if tailored strategies specific to people at different stages of retention have the potential to improve outcomes of OAT.

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.

Synthetic opioids: a review and clinical update

The term 'opioids' refers to both the natural compounds ('opiates') which are extracted from the opium poppy plant (Papaver somniferum) and their semi-synthetic and synthetic derivatives. They all possess relatively similar biochemical profiles and interact with the opioid receptors within the human body to produce a wide range of physiological effects. They have historically been used for medicinal purposes, their analgesic and sedative effects, and in the management of chronic and severe pain. They have also been used for non-medicinal and recreational purposes to produce feelings of relaxation, euphoria and well-being. Over the last decade, the emergence of an illegal market in new synthetic opioids has become a major global public health issue, associated with a substantial increase in unintentional overdoses and drug-related deaths. Synthetic opioids include fentanyl, its analogues and emerging non-fentanyl opioids. Their popularity relates to changes in criminal markets, pricing, potency, availability compared to classic opioids, ease of transport and use, rapid effect and lack of detection by conventional testing technologies. This article expands on our previous review on new psychoactive substances. We now provide a more in-depth review on synthetic opioids and explore the current challenges faced by people who use drugs, healthcare professionals, and global public health systems.

Shifting North American drug markets and challenges for the system of care

Drug markets are dynamic systems which change based on demand, competition, legislation and revenue. Shifts that are not met with immediate and appropriate responses from the healthcare system can lead to public health crises with tragic levels of morbidity and mortality, as experienced Europe in the early 1990s and as is the case in North America currently. The major feature of the current drug market shift in North America is towards highly potent synthetic opioids such as fentanyl and fentanyl analogues. An additional spike in stimulant use further complicates this issue. Without understanding the ever-changing dynamics of drug markets and consequent patterns of drug use, the healthcare system will continue to be ineffective in its response, and morbidity and mortality will continue to increase. Economic perspectives are largely neglected in research and clinical contexts, but better treatment alternatives need to consider the large-scale macroeconomic conditions of drug markets as well as the behavioural economics of individual substance use. It is important for policy makers, health authorities, first responders and medical providers to be aware of the clinical implications of drug market changes in order to best serve people who use drugs. Only with significant clinical research, a comprehensive reorganization of the system of care across all sectors, and an evidence-driven governance, will we be successful in addressing the challenges brought on by the recent shifts in drug markets.

Treatment of overdose in the synthetic opioid era

Overdose deaths are often viewed as the leading edge of the opioid epidemic which has gripped the United States over the past two decades (Skolnick, 2018a). This emphasis is perhaps unsurprising because opioid overdose is both the number-one cause of death for individuals between 25 and 64 years old (Dezfulian et al., 2021) and a significant contributor to the decline in average lifespan (Dowell et al., 2017). Exacerbated by the COVID 19 pandemic, it was estimated there were 93,400 drug overdose deaths in the United States during the 12 months ending December 2020, with more than 69,000 (that is, >74%) of these fatalities attributed to opioid overdose (Ahmad et al., 2021). However, the focus on mortality statistics (Ahmad et al., 2021; Shover et al., 2020) tends to obscure the broader medical impact of nonfatal opioid overdose. Analyses of multiple databases indicate that for each opioid-induced fatality, there are between 6.4 and 8.4 non-fatal overdoses, exacting a significant burden on both the individual and society. Over the past 7-8 years, there has been an alarming increase in the misuse of synthetic opioids ("synthetics"), primarily fentanyl and related piperidine-based analogs. Within the past 2-3 years, a structurally unrelated class of high potency synthetics, benzimidazoles exemplified by etonitazene and isotonitazene ("iso"), have also appeared in illicit drug markets (Thompson, 2020; Ujvary et al. 2021). In 2020, it was estimated that over 80% of fatal opioid overdoses in the United States now involve synthetics (Ahmad et al., 2021). The unique physicochemical and pharmacological properties of synthetics described in this review are responsible for both the morbidity and mortality associated with their misuse as well as their widespread availability. This dramatic increase in the misuse of synthetics is often referred to as the "3rd wave" (Pardo et al., 2019; Volkow and Blanco, 2020) of the opioid epidemic. Among the consequences resulting from misuse of these potent opioids is the need for higher doses of the competitive antagonist, naloxone, to reverse an overdose. The development of more effective reversal agents such as those described in this review is an essential component of a tripartite strategy (Volkow and Collins, 2017) to reduce the biopsychosocial impact of opioid misuse in the "synthetic era".

Prevalence of new psychoactive substances (NPS) in Brazil based on oral fluid analysis of samples collected at electronic music festivals and parties

BACKGROUND

New psychoactive substances (NPS) use is a worldwide public health issue. Knowing the prevalence of NPS guides public health and legal policies to address the problem. The objective of this study was to identify NPS in Brazil through the analysis of oral fluid (OF) samples collected at parties and electronic music festivals.

METHODS

Anonymous questionnaires and oral fluid samples were collected from volunteers (≥18 years) who reported the consumption of at least one illicit psychoactive substance in the last 24 h. Oral fluid sample collections occurred at eleven parties and two electronic music festivals over 16 months (2018-2020). Questionnaire answers were matched to oral fluid toxicological results.

RESULTS

Of 462 oral fluid samples, 39.2 % were positive for at least one NPS by liquid chromatography‒tandem mass spectrometry (LC-MS/MS). The most prevalent NPS was ketamine (29.4 %), followed by methylone (6.1 %) and N-ethylpentylone (4.1 %); however, MDMA was the most commonly identified (88.5 %) illicit psychoactive substance. More than one drug was identified in 79.9 % of samples, with two (34.2 %) and three (23.4 %) substances most commonly observed. Only 5 % of volunteers reported recent NPS consumption.

CONCLUSION

MDMA is still the most common party and electronic music festival drug, although NPS were identified in more than one-third of oral fluid samples.

Ocfentanil testing in hair from a fatality case: Comparative analysis of a lock of hair versus a single hair fiber

In clinical and forensic toxicology, hair analysis offers a larger window for detecting drug exposure than blood or urine. Drug measurements are generally carried out using a segmented lock of hair, but few articles report the use of a single hair to document drug exposure. Nevertheless, single hair analysis can be very useful, particularly if only small amounts of biological matrices are available. More data on analyzing new synthetic opioids (NSOs) in hair are needed to help interpretation in future cases. In this study, segmental single hair analysis is compared with segmental hair lock analysis to document an ocfentanil-related death. The hair lock and single hair analyses were performed using the LC-MS/MS method after decontamination and incubation. Ocfentanil (OcF) concentrations ranged from 42 to 150 pg/mg in the segmented hair lock, depending on the segments. The hair lock and single hair analyses showed similar results: the highest concentrations were measured in the first two centimeters and decreased from root to tip. The similar profiles obtained from both the lock of hair and the single hair demonstrate the relevance of single hair analysis in cases where very few data are available. This article describes OcF concentrations in an authentic hair sample after a documented intake of this molecule in a fatality.

The opioid overdose crisis as a global health challenge

PURPOSE OF REVIEW

To assess the current state of the opioid overdose crisis along three major axes: drug markets and patterns of use, the effectiveness of systems of care, and international developments.

RECENT FINDINGS

Overdose is a major contributor to mortality and disability among people who use drugs. The increasing number of opioid overdoses in North America especially is an indication of changing drug markets and failing regional systems of care. Globally, we see three clusters of overdose prevalence: (1) a group of countries led by the United States with historically high rates of opioid overdose, (2) a group of countries with increasing rates within a concerning range, (3) a group with very low rates. The contamination of street drugs, the quality and accessibility of treatment, and the overall system of care all contribute to the prevalence of overdose.

SUMMARY

Drug markets and pattern of consumption in parts of the world are shifting towards contamination and opioids like fentanyl as the drug of choice, which dismantles insufficient and largely ineffective systems of care. Furthermore, outside of North America, more countries like Estonia, Lithuania, Sweden, Finland, and Norway show very concerning numbers. Without a consistent system response, effects will be devastating.

Overdoses due to fentanyl and its analogues (F/FAs) push naloxone to the limit

WHAT IS KNOWN AND OBJECTIVE

Food and Drug Administration (FDA) risk evaluation and mitigation strategies (REMs) encourage emergency responders, paramedics, law enforcement agents, and even laypeople to be trained in the administration of naloxone with the intent of rescuing individuals from a known or suspected opioid overdose.

COMMENT

Although naloxone is generally safe and effective at reversing respiratory depression caused by a conventional opioid such as morphine or heroin by competing with the opioid and displacing it from the μ-opioid receptor, questions increasingly are arising as to whether naloxone can adequately reverse opioid overdoses that may involve the potent opioids fentanyl and its analogues (F/FAs). In other words, as more and more opioid overdoses involve F/FAs, can naloxone keep up?

WHAT IS NEW AND CONCLUSION

As a competitive antagonist at μ-opioid receptors, naloxone is often a life-saving agent in cases of overdose caused by conventional opioids, but it may not be versatile or powerful enough to combat the rising tide of overdoses due to fentanyl and its illicit analogues, or in cases of overdose involving combinations of opioids and non-opioids.

Gas Chromatography-Mass Spectrometry Analysis of Synthetic Opioids Belonging to the Fentanyl Class: A Review

The rising number of deaths caused by fentanyl overdosing in the US due to the overwhelming illicit use of this synthetic opioid has started a global campaign to develop efficient ways to control its production and distribution as well as discovering efficient antidotes to mitigate its lethal effects. Another important vein of focused research established by various agencies lies in the development of efficient and practical protocols for the detection of this opioid and analogs thereof in various matrices, whether environmental or biological in nature, particularly in the field of gas chromatography-mass spectrometry (GC-MS). The following review will cover the literature dealing with the detection and identification of synthetic opioids belonging to the fentanyl class by GC-MS means and hyphenated versions of the technique. Detailed descriptions will be given for the GC-MS methods employed for the analysis of the opioid, starting with the nature of the extraction protocol employed prior to analysis to the actual findings presented by the cited reports. Great effort has gone into describing the methods involved in each paper in a detailed manner and these have been compiled by year in tables at the end of each section for the reader's convenience. Lastly, the review will end with concluding remarks about the state of GC-MS analysis with regards to these powerful opioids and what lies ahead for this analytical field.

Identification of human cytochrome P450 isozymes involved in the oxidative metabolism of carfentanil

Carfentanil is an ultra-potent opioid with an analgesic potency 10,000 times that of morphine but has received little scientific investigation. In the present study, the human cytochrome P450 (CYP) isozymes catalyzing the oxidative metabolism of carfentanil were investigated. Using UHPLC-HRMS, Michaelis-Menten kinetics of formation for three major metabolites norcarfentanil (M1), pharmaceutical active metabolite 4-[(1-oxopropyl)phenylamino]-1-(2-hydroxyl-2-phenylethyl)-4-piperidinecarboxylic acid methyl ester (M11), and 4-[(1-oxopropyl)phenylamino]-1-(2-oxo-2-phenylethyl)-4-piperidinecarboxylic acid methyl ester (M15) were determined. Isozymes catalyzing the formation of the low abundant, highly active metabolite 1-[2-(2-hydroxylphenyl)ethyl]-4-[(1-oxopropyl)phenylamino]-4-piperidinecarboxylic acid methyl ester (M13) were also identified. Selective P450 inhibition studies with pooled human liver microsomes (HLMs) and recombinant CYP isozymes suggested that metabolites M1, M11, and M15 were predominantly formed by isozyme CYP3A5, followed by CYP3A4. Isozymes CYP2C8 and CYP2C9 also made contributions but to a much lesser extent. Highly potent metabolite M13 was predominantly formed by isozyme CYP2C9, followed by CYP2C8. These findings indicate that CYP3A5, CYP3A4, CYP2C8 and CYP2C9 play a major role in the transformation of carfentanil to M1 (norcarfentanil), M11, M13 and M15 through N-dealkylation of piperidine ring, hydroxylation of phenethyl group and ketone formation on phenethyl linker by human liver micrsomes.

Paper Spray Mass Spectrometry Utilized with a Synthetic Microporous Polyolefin Silica Matrix Substrate in the Rapid Detection and Identification of More than 190 Synthetic Fentanyl Analogs

Fentanyl and its related synthetic analogs have recently become more readily available as a growing threat to public safety, such as pain relief and anesthetics. Sources of fentanyl are more likely to be illicitly manufactured than pharmaceutically manufactured and are often laced with other opioids, which ultimately increases the potency of fentanyl and results in an increased number of overdose deaths. The methods used to detect these compounds safely and quickly are of high interest due to their extreme potency. This study investigates the use of paper spray mass spectrometry (PS-MS), which is a simple atmospheric ionization process that can be used as a rapid study (60 s) with limited sample preparation and sample handling. PS-MS can be utilized with a synthetic microporous polyolefin silica matrix substrate, known as Teslin, which is manufactured by PPG Industries. The main characteristic of paper spray ionization with the Teslin substrate is the hydrophobicity, which is useful for a fast and direct analysis requiring only 1 μg of the sample. The application of this novel synthetic substrate to PS-MS has been illustrated with a fentanyl analog screening kit (FAS Kit), which was designed by the Centers for Disease Control (CDC) for the screening of 212 evolving synthetic opioids, including more than 190 fentanyl analogs. The comparable fragmentation with precursor molecule mass data from this study can be useful in improving the accurate detection and structural characterization of complex samples with a minimum interference of the isobaric components.

Carfentanil - from an animal anesthetic to a deadly illicit drug

The use of novel synthetic opioids as recreational drugs has become a public health concern as they are implicated in numerous fatal intoxications across the world. Synthetic opioids have played a major role in the United States opioid crisis and may contribute to a similar opioid epidemic in Europe. The most prominent group of designer opioids consists of fentanyl and its analogues. At present, carfentanil is the most dangerous fentanyl derivative. It was recently detected as an adulterant to other illicit drugs and counterfeit pharmaceuticals, contributing to life-threatening hospital admissions and fatalities. Toxic exposure to carfentanil typically occurs through injection, insufflation or inhalation. Carfentanil produces similar pharmacotoxicological effects to other opioids. However, due to its extraordinary potency, reversing carfentanil-induced severe and recurring respiratory depression requires administration of multiple or higher than standard doses of naloxone. Toxicological reports indicate that carfentanil use is strongly connected to polydrug use. Detection of carfentanil requires specific and sensitive analytical methods that are not commonly available in hospitals. Since abuse of carfentanil is an emerging problem, particularly in the United States, there is an urgent need to develop new techniques for rapid determination of intoxication evoked by this drug as well as new treatment regimens for effective overdose maintenance. This review presents current knowledge on pharmacological activity of carfentanil, prevalence and patterns of use, and analytical methods of its detection. Special emphasis is given to carfentanil-related non-fatal and lethal overdose cases.

Carfentanil on the darknet: Potential scam or alarming public health threat?

BACKGROUND

In an age of global insecurity, highly potent synthetic drugs have become a major public health issue. Their online advertisement and sale are facilitated by surface web, darknet markets and social media fuelling substance abuse and addiction, as well as various types of new criminal activities and their growth in sophistication. This study presents a systematic analysis of the darknet sale of one of the most potent synthetic opioids: Carfentanil. With an equianalgesic potency of 10.000 times a unit of morphine, its toxicity is comparable to traditional nerve agents, and it has been previously used as a chemical weapon, causing human fatalities.

METHODS

Digital trace data was collected retrospectively from all the darknet marketplaces, which have been active in the past five years. Data on vendors offering Carfentanil on Agartha, Empire and Yakuza marketplaces were analysed with regard to items sold and sellers' features as these were the only active markets at the time of search. Searches were carried out in the English language only.

RESULTS

63 Cartfentanil vendors operating on 19 darknet marketplaces were identified. Contacts and payments were facilitated with end-to-end encryption messaging mobile applications and content-expiring messages. Although it is known that Agartha is a scam market, and no operative sellers were found on Yakuza, several sellers promoting Carfentanil sales were active in the Empire marketplace with a number of transaction ranging from 4 to 1223.

CONCLUSION

The availability of highly potent drugs such as Carfentanil on the darknet requires the urgent development of novel scientific methods and tools able to monitor and to predict such new threats, while informing policymaking and protecting the health and the security of citizens.

Why Switch? - Motivations for Self-Substitution of Illegal Drugs

Self-substitution is the conscious switch from one drug to another for reasons such as price, availability, desired effect, or perceived benefit of the substitute drug. Purpose/Objectives: This study aimed to describe drug use patterns and motivations associated with substitution. We examined correlates of lifetime substitution among individuals with substance use disorder. Methods: A cross-sectional study of 771 treatment-enrolled individuals. We used self-report for determining the lifetime prevalence, correlates, and motivations for substitution. Results: Of the 771 respondents, 570 (73.9%) reported ever substituting their preferred substance. The main incentives for substitution were availability (23.7%) and curiosity (20.2%). Among heroin or cannabis preferers, improved effects or less adverse effects of the substitute drug, self-medication, and managing withdrawal symptoms were significant substitution incentives. Increased odds for substitution were observed for past 12 months use of cannabis (OR = 1.51, CI = 1.06-4.52), prescription opioids (OR = 2.86, CI = 1.81-4.52), novel psychoactive substances (OR = 2.68, CI = 1.64-4.36), and repeated admission (OR = 1.50, CI = 1.05-2.14). Older age at onset-of-use was negatively associated with substitution (OR = 0.95, CI = 0.93-0.98). Conclusions: Self-substitution of one substance for another is a highly prevalent behavior among treatment-enrolled patients with substance use disorder. Clinicians caring for substance use disorder patients should be aware of substitution patterns involving the use of highly potent substances, which constitutes a risk to patients. Results underscore the benefit of substitution patterns analyses, as they reveal important information on the characteristics of persons who use drugs and their motivations.

Use and knowledge of novel synthetic opioids: An Italian survey

The recreational use of novel synthetic opioids (NSOs) is increasing, especially among the youngest part of the population. We conducted a naturalistic observational survey. The main outcome was to assess the use and the knowledge of NSOs among the youngest population in Italy. A sociodemographic questionnaire was also administrated. Nine hundred twenty questionnaires were completed. Fentanyl was the most used NSO (1.63% of the subjects). In all, 14.3% of the sample revealed awareness of NSOs. Although the diffusion in Italy is small, the large knowledge of NSOs requires future monitoring of this phenomenon.

A Semi-quantitative method for the detection of fentanyl using surface-enhanced Raman scattering (SERS) with a handheld Raman instrument

A handheld, spatially offset Raman spectroscopy (SORS) system was successfully used to obtain Surface-enhanced Raman Scattering (SERS) spectra of fentanyl under simulated field conditions. A series of aqueous fentanyl solutions were prepared with commercially available gold nanoparticle solution, at concentrations ranging from 0.003 to 1697 μM. These SERS spectra were then used to generate two concentration calibration models (via a plot of peak area (1026 cm^-1 ) versus concentration, and quantitative spectral decomposition using partial least squares (PLS1)). For both models, the relationship followed Langmuir adsorption and became non-linear at concentrations above ~0.2 μM, with a limit of detection (LOD) of approximately 3 nM. The same technique was successfully used to measure fentanyl in the presence of two common "cutting agents," heroin and glucose, at 1% and 2% fentanyl proportions (w/w). Fentanyl detection was successfully achieved, but mixture interference from the cutting agents prevented a calibration model being generated. Four fentanyl analogues were also investigated-butyrylfentanyl, furanylfentanyl, acetylfentanyl, and ocfentanyl. A concentration calibration model for each species was successfully generated, but differentiation from fentanyl proved more challenging, although several potential diagnostic peaks were identified. These results identified a pathway forward in using handheld equipment for the reliable detection of ultra-low concentrations of fentanyl and fentanyl analogues via SERS, even when mixed with diluents. However, quantitative detection is negatively impacted in the presence of heroin and glucose. This also provides a starting point for a SERS-based spectral library of fentanyl analogues, in combination with a range of different diluents.

DARK Classics in Chemical Neuroscience: Carfentanil

Because of its remarkable potency and relative ease of synthesis, carfentanil (1) has recently emerged as a problematic contaminant in other drugs of abuse. Carfentanil and its close analogs, currently approved only for large animal veterinary medicine, have found use both as illicit additives to the clandestine manufacture of scheduled drugs and as chemical weapons. In this Review, the background, synthesis, manufacture, metabolism, pharmacology, approved indications, dosage, and adverse effects of carfentanil will be discussed along with its emergence as a key player in the ongoing opioid crisis.

The switch from one substance-of-abuse to another: illicit drug substitution behaviors in a sample of high-risk drug users

Background

Substitution can be defined as the consciously motivated choice to use one drug, either licit or illicit, instead of another, due to perceptions of cost, availability, safety, legality, substance characteristics, and substance attributions. Substitution represents a potential risk to drug users, mainly when substitutes are of higher potency and toxicity. This study offers a basic conceptualization of illicit substitution behavior and describes substitution patterns among users of two highly prevalent drugs of abuse-heroin and cannabis.

Methods

Here, 592 high-risk drug users undergoing pharmacological and psycho-social treatment were interviewed. Patients were asked questions about current drug use, lifetime substitution, and substitution patterns. Descriptive statistics, chi-square tests of independence, and multinomial logistic regressions were used to identify and test correlates of substitution patterns for heroin and cannabis.

Results

Of the 592 drug users interviewed, 448 subjects (75.7%) reported having substituted their preferred drug for another illicit substance. Interviews yielded a total of 275 substitution events reported by users of cannabis, and 351 substitution events reported by users of heroin. The most frequently reported substitution substances for responders who preferred heroin were illicit non-prescribed "street" methadone (35.9%), followed by oral and transdermal prescription opioids (17.7%). For responders who preferred cannabis, substitution for synthetic cannabinoid receptor agonists (33.5%) followed by alcohol (16.0%) were the most commonly reported. Age at onset-of-use (p < 0.005), population group (p = 0.008), and attending treatment for the first time (p = 0.026) were significantly associated with reported lifetime substitution. Past-year use of stimulants, heroin, hallucinogens, methylenedioxymethamphetamine (MDMA), and novel psychoactive substances were-at the 95% confidence level-also significantly associated with reported lifetime substitution. In multivariate analysis, the odds for methadone substitution among heroin users were significantly affected by age at onset-of-use, type of treatment center, and education. Odds for substitution for synthetic cannabinoid receptor agonists among cannabis users were significantly affected by age, population group, type of treatment center, and education.

Conclusion

Self-substitution behavior should be considered by clinicians and policymakers as a common practice among most drugusers. Substitution for street methadone provides evidence for the ongoing diversion of this substance from Opioid Maintenance Treatment Centers, while the prominence of substitution of synthetic cannabinoids among dual-diagnosis patients should be regarded as an ongoing risk to patients that needs to be addressed by clinicians. Analysis of additional substitution patterns should provide further valuable insights into the behavior of drugusers.

Determination of fentanyl and 19 derivatives in hair: Application to an Italian population

Nowadays fentanyl and its analogs represent the most numerous group among synthetic opioid and, due to their higher potency in comparison to traditionl opioids, the main cause of the critical increase of fatal intoxications opioids-intake related in the USA. We developed an LC-MS/MS method for the detection and quantification of fentanyl and its analogs in hair, then applied to 117 real samples, 97 collected from drugs users and 20 from postmortem cases of drugs addicts. The ionization and MRM parameters have been optimized for 27 molecules: 20 reached the acceptance criteria for identification and quantification. LODs and LOQs of 0.2 and 0.5 pg/mg, respectively, were reached for most of the substances, except for five compounds for which were set at 0.5 and 1.0 pg/mg. 2 out of the 97 samples collected from drug users tested positive; one for carfentanil, butyryl fentanyl, THFF and ocfentanil; the other one for 3-methyl norfentanyl. 2 out of the 20 postmortem samples show positive results: one only for fentanyl, the other for furanyl fentanyl, acetyl fentanyl, methoxyacetyl fentanyl, methoxyacetyl norfentanyl, ocfentanil and 4-ANPP. Despite the relatively small number of samples, the results suggest that the method should be included in routine hair analyses for monitoring the new synthetic opioids potential intake by drug users.

The opioid epidemic in pediatrics: a 2020 update

PURPOSE OF REVIEW

Over the last 3 years and for the first time in 60 years, life expectancy in the United States has declined across all racial groups primarily because of drug overdoses, alcohol abuse, and suicide. A public health response to the opioid crisis must expand its focus to more broadly include children, adolescents, and young adults while increasing efforts toward preventing new cases of opioid addiction, early identification of individuals with opioid-abuse disorder, and ensuring access to effective opioid addiction treatment, while simultaneously continuing to safely meet the needs of patients experiencing pain.

RECENT FINDINGS

Although a multimodal approach to pain management is fundamental in current practice, opioids remain an essential building block in the management of acute and chronic pain and have been for over 5000 years as they work. Left over, unconsumed opioids that were appropriately prescribed for pain have become the gateway for the development of opioid use disorder, particularly in the vulnerable adolescents and young adult patient populations. How to reduce the amount of opioids dispensed, improve methods of disposal in an environmentally safe way, and proactively make naloxone, particularly nasal spray, readily available to patients (and their families) receiving prescription opioids or who are at risk of opioid use disorder are highlighted in this review.

SUMMARY

We describe the historical use of opioids and the scope of the current opioid crisis, review the differences between dependence and addiction, and the private and public sectors response to pain management and highlight the issue of adolescent vulnerability. We conclude with a proposal for future directions that address both public and patient health needs.

Mass spectral similarity mapping applied to fentanyl analogs

This manuscript outlines a straight-forward procedure for generating a map of similarity between spectra of a set. When applied to a reference set of spectra for Type I fentanyl analogs (molecules differing from fentanyl by a single modification), the map illuminates clustering that is applicable to automated structure assignment of unidentified molecules. An open-source software implementation that generates mass spectral similarity mappings of unknowns against a library of Type I fentanyl analog spectra is available at http://github.com/asm3-nist/FentanylClassifier.

Interpol review of controlled substances 2016-2019

This review paper covers the forensic-relevant literature in controlled substances from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20Papers%202019.pdf.

Interpol review of toxicology 2016-2019

This review paper covers the forensic-relevant literature in toxicology from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20.Papers%202019.pdf.

Opioid agonist treatment and risk of mortality during opioid overdose public health emergency: population based retrospective cohort study

OBJECTIVE

To compare the risk of mortality among people with opioid use disorder on and off opioid agonist treatment (OAT) in a setting with a high prevalence of illicitly manufactured fentanyl and other potent synthetic opioids in the illicit drug supply.

DESIGN

Population based retrospective cohort study.

SETTING

Individual level linkage of five health administrative datasets capturing drug dispensations, hospital admissions, physician billing records, ambulatory care reports, and deaths in British Columbia, Canada.

PARTICIPANTS

55 347 people with opioid use disorder who received OAT between 1 January 1996 and 30 September 2018.

MAIN OUTCOME MEASURES

All cause and cause specific crude mortality rates (per 1000 person years) to determine absolute risk of mortality and all cause age and sex standardised mortality ratios to determine relative risk of mortality compared with the general population. Mortality risk was calculated according to treatment status (on OAT, off OAT), time since starting and stopping treatment (1, 2, 3-4, 5-12, >12 weeks), and medication type (methadone, buprenorphine/naloxone). Adjusted risk ratios compared the relative risk of mortality on and off OAT over time as fentanyl became more prevalent in the illicit drug supply.

RESULTS

7030 (12.7%) of 55 347 OAT recipients died during follow-up. The all cause standardised mortality ratio was substantially lower on OAT (4.6, 95% confidence interval 4.4 to 4.8) than off OAT (9.7, 9.5 to 10.0). In a period of increasing prevalence of fentanyl, the relative risk of mortality off OAT was 2.1 (95% confidence interval 1.8 to 2.4) times higher than on OAT before the introduction of fentanyl, increasing to 3.4 (2.8 to 4.3) at the end of the study period (65% increase in relative risk).

CONCLUSIONS

Retention on OAT is associated with substantial reductions in the risk of mortality for people with opioid use disorder. The protective effect of OAT on mortality increased as fentanyl and other synthetic opioids became common in the illicit drug supply, whereas the risk of mortality remained high off OAT. As fentanyl becomes more widespread globally, these findings highlight the importance of interventions that improve retention on opioid agonist treatment and prevent recipients from stopping treatment.

Novel Opioids: Systematic Web Crawling Within the e-Psychonauts' Scenario

Background

A wide range of novel psychoactive substances (NPSs) are regularly searched and discussed online by e-psychonauts. Among NPSs, the range of prescription/non-prescription opioids (fentanyl and non-fentanyl analogs) and herbal derivatives currently represents a challenge for governments and clinicians.

Methods

Using a web crawler (i.e., NPS.Finder^®), the present study aimed at assessing psychonaut fora/platforms to better understand the online situation regarding opioids.

Results

The open-web crawling/navigating software identified some 426 opioids, including 234 fentanyl analogs. Of these, 176 substances (162 were very potent fentanyls, including two ohmefentanyl and seven carfentanyl analogs) were not listed in either international or European NPS databases.

Conclusion

A web crawling approach helped in identifying a large number, indeed higher than that listed by European/international agencies, of unknown opioids likely to possess a significant misuse potential. Most of these novel/emerging substances are still relatively unknown. This is a reason of concern; each of these analogs potentially presents with different toxicodynamic profiles, and there is a lack of docking, preclinical, and clinical observations. Strengthening multidisciplinary collaboration between clinicians and bioinformatics may prove useful in better assessing public health risks associated with opioids.

Synthetic psychoactive cathinones: hypothermia and reduced lethality compared to methamphetamine and methylenedioxymethamphetamine

RATIONALE

Synthetic psychoactive cathinones (SPCs) are drugs with psychostimulant and entactogenic properties like methamphetamine (MA) and 3,4-methylenedioxymethamphetamine (MDMA). Despite clinical reports of human overdose, it remains to be determined if SPCs have greater propensity for adverse effects than MA or MDMA.

OBJECTIVES

To determine whether the SPCs cathinone (CAT), methcathinone (MCAT), mephedrone (MMC), and methylenedioxypyrovalerone (MDPV) have lower LD50 values than MA or MDMA.

METHODS

Male and female C57Bl/6J mice received single injections of one of 6 doses of a test drug (0-160 mg/kg IP). Temperature and behavioral observations were taken every 20 min for 2 h followed by euthanasia of surviving mice. Organs were weighed and evaluated for histopathological changes.

RESULTS

LD50 values for MA and MDMA, 84.5 and 100.9 mg/kg respectively, were similar to previous observations. The LD50 for MMC was 118.8 mg/kg, but limited lethality was observed for other SPCs (CAT, MCAT, MDPV), so LD50 values could not be calculated. For all drugs, death was associated with seizure, when it was observed. Rather than hyperthermia, dose-dependent hypothermia was observed for MMC, MDPV, CAT, and MCAT. Contrary to initial expectations, none of the SPCs studied here had LD50 values lower than MA or MDMA.

CONCLUSIONS

These data indicate that, under the conditions studied here: (1) SPCs exhibit less lethality than MA and MDMA; (2) SPCs impair thermoregulation; (3) effects of SPCs on temperature appear to be independent of effects on lethality.

[Chemical warfare agent poisoning]

Despite long-lasting international efforts to ban and disarm chemical warfare agents (CWAs), they pose an ongoing threat to the population. The reasons for this are existing remainders, inappropriately disposed of chemical munitions and availability of instructions for synthesis in open literature. Dissemination of CWAs during war, warlike conflicts and terrorist incidents has recently resulted in thousands of deaths. In this manuscript CWAs and comparable substances are presented and the signs and symptoms of poisoning with these substances are described. Aside from clear recommendations for the treatment of poisoning by the single groups of CWAs, parallels to well-known related poisonings including pathophysiological similarities are demonstrated. Moreover, aspects of detection, diagnosis and general management, such as decontamination, verification and antidote stockpiling, are described.According to the respective pathophysiological target, CWAs are classified as lung, skin, nerve and incapacitating agents. They are generally liquids at ambient room temperature and are more or less able to vaporise. In recent years, pharmaceutical-based agents (PBAs) came on board although they are not listed in the chemical warfare convention and therefore not listed as CWAs. Due to their high toxicity, however, they are mentioned here. PBAs comprise, for example, synthetic opioids which can act after inhalative respiration.During the rescue of affected victims, early detection of CWAs, restriction of access to the contaminated area and use of protective clothes and masks by first responders are necessary. Exposure should be terminated as soon as possible by removal of the victim from the hot zone and decontamination. The latter is also important to avoid secondary contamination of other persons or facilities located outside of the contaminated zone. According to the type of poisoning, therapy should be started as soon as possible.