Severe Toxicity to the New Psychoactive Substances 3-Hydroxyphencyclidine and N-Ethylhexedrone: an Analytically Confirmed Case Report

Hair-based rapid UPLC-MS/MS analysis of 36 phencyclidine-type substances in forensic cases

Phencyclidine (PCP) is a frequently abused dissociative agent. It causes confusion, increased tendencies toward violence, and concentration-dependent cytotoxicity after entry into the body. The parent nucleus of phencyclidine-type substances is arylcyclohexylamine, which is easy to modify; therefore, abusers and dealers can readily synthesize substitutes beyond the drug control catalog. An urgent need exists to establish screening methods for phencyclidine-type substances to provide technical support for abuse monitoring. In this study, 20 mg of hair was pulverized in 500 mL of methanol containing 0.5 ng/mL PCP-d5. After ultrasonication, centrifugation, and filtration, the supernatant was analyzed by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) operating in the multiple reaction monitoring mode. Phencyclidine-type substances were separated in 13 min on a biphenyl column using a mobile phase gradient composed of A (water, formic acid 0.1%, acetonitrile 5%, 20 mmol/L ammonium acetate) and B (acetonitrile). The developed and validated method showed good selectivity, sensitivity (limit of detection: 0.25-2 pg/mg and lower limit of quantitation: 0.5-4 pg/mg), linearity (R2 > 0.994), accuracy, and precision (< 20%), and a dilution effect. The method also showed good recovery and acceptable matrix effects for most of the targeted compounds. This analytical approach was successfully applied for the identification and quantification of phencyclidine-type substances in hair from 87 authentic forensic cases. Nine analytes were detected: ketamine (10.3-26211.3 pg/mg), 2-F-2-oxo-PCE (11.5-4034.9 pg/mg), 2-FDCK (14.0-43290.2 pg/mg), 2-BrDCK (10.6-21170.0 pg/mg), nor2-FDCK (10.1-16767.4 pg/mg), tiletamine (10.1-3250.8 pg/mg), O-PCE (43.3-166.1 pg/mg), DCK (10.2-90.4 pg/mg), and norDCK (24.9-103.0 pg/mg).

New trends of new psychoactive substances (NPS)-infused chocolate: Identification and quantification of trace level of NPS in complex matrix by GC-MS and NMR

For the first time, the identification and quantification of trace level of new psychoactive substances (NPS) in a complex chocolate matrix have been reported. Since the beginning of 2022, suspected NPS-infused chocolate samples confiscated in inbound packages have been continuously sent to our laboratory for analysis. The qualitative gas chromatography-mass spectrometry (GC-MS) results were verified by ¹H nuclear magnetic resonance (¹H NMR) and ¹⁹F NMR to distinguish between potential aromatic isomers. A total of 11 NPS including deoxymethoxetamine, 3-OH-PCP, 6-APB, 4-APB, 4-OH-MiPT, 3-FEA, 2-FEA, 3-MMC, bromazolam, 2-FDCK, and ADB-BUTINACA were detected in 65 seized chocolate samples. A general ¹H quantitative NMR (¹H qNMR) method for quantification of 297 types of NPS in complex chocolate matrixes was devised for the first time after rigorous analysis of various critical features of merit, including suitable deuterated solvent, internal standard, quantitative peaks, and instrument acquisition parameters. Validation of the method using six different types of NPS afforded limits of detection of 0.05-0.1 mg/mL, limits of quantification of 0.01-0.03 mg/mL, repeatability and reproducibility lower than 0.5% and 3.6%, recoveries of 91.7%∼104.4%, and absence of matrix effect. The quantitative analysis of 65 seized chocolate samples by ¹H qNMR and ¹⁹F qNMR showed that the content of NPS was in the range of 0.5 mg/g∼44.1 mg/g. Generally, the developed qNMR method was simple, fast, precise, and can be performed without reference materials of NPS. Since the type and content of NPS are relatively random, chocolate consumers will face huge health risks. Therefore, this new trend of NPS-infused chocolate deserves and requires more attention from national NPS monitoring departments as well as forensic laboratories.

Structure-Activity Relationship of N-Ethyl-Hexedrone Analogues: Role of the α-Carbon Side-Chain Length in the Mechanism of Action, Cytotoxicity, and Behavioral Effects in Mice

Synthetic cathinones are β-keto amphetamine derivatives whose appearance has increased dramatically in the past decades. N-Ethyl substituted cathinones have been proven to potently inhibit dopamine (DA) uptake and induce psychostimulant and rewarding effects in mice. However, little is known about the influence of the alpha-carbon side-chain length of N-ethyl cathinones on their pharmacological and toxicological effects. Thus, the aim of this study was to synthesize and investigate the in vitro and in vivo effects of five N-ethyl substituted cathinones: N-ethyl-cathinone (NEC), N-ethyl-buphedrone (NEB), N-ethyl-pentedrone, N-ethyl-hexedrone (NEH), and N-ethyl-heptedrone. HEK293 cells expressing the human DA or serotonin transporter (hDAT and hSERT) were used for uptake inhibition and binding assays. PC12 cells were used for the cytotoxicity assays. Swiss CD-1 mice were used to study the in vivo psychostimulant, anxiogenic, and rewarding properties. Our results show that all tested cathinones are able to inhibit DA uptake and are DAT-selective. The potency of DA uptake inhibitors increases with the elongation of the aliphatic side chain from methyl to propyl and decreases when increasing from butyl to pentyl, which correlates with an inverted U-shape psychostimulant response in mice at the medium dose tested. On the other hand, an increase in the α-carbon side-chain length correlates with an increase in the cytotoxic properties in PC12 cells, probably due to better membrane penetration. Moreover, all the cathinones tested have shown higher cytotoxicity than methamphetamine. Finally, our study not only demonstrated the rewarding properties of NEC and NEB but also the anxiety-like behavior induced at high doses by all the cathinones tested.

A review of synthetic cathinones emerging in recent years (2019-2022)

Purpose

The emergence of novel psychoactive substances (NPS) has been being a continuous and evolving problem for more than a decade. Every year, dozens of new, previously unknown drugs appear on the illegal market, posing a significant threat to the health and lives of their users. Synthetic cathinones are one of the most numerous and widespread groups among NPS. The purpose of this work was to identify and summarize available data on newly emerging cathinones in very recent years.

Methods

Various online databases such as PubMed, Google Scholar, but also databases of government agencies including those involved in early warning systems, were used in search of reports on the identification of newly emerging synthetic cathinones. In addition, threads on various forums created by users of these drugs were searched for reports on the effects of these new substances.

Results

We have identified 29 synthetic cathinones that have been detected for the first time from early 2019 to mid-2022. We described their structures, known intoxication symptoms, detected concentrations in biological material in poisoning cases, as well as the countries and dates of their first appearance. Due to the lack of studies on the properties of the novel compounds, we compared data on the pharmacological profiles of the better-known synthetic cathinones with available information on the newly emerged ones. Some of these new agents already posed a threat, as the first cases of poisonings, including fatal ones, have been reported.

Conclusions

Most of the newly developed synthetic cathinones can be seen as analogs and replacements for once-popular compounds that have been declining in popularity as a result of legislative efforts. Although it appears that some of the newly emerging cathinones are not widely used, they may become more popular in the future and could become a significant threat to health and life. Therefore, it is important to continue developing early warning systems and identifying new compounds so that their widespread can be prevented.

Reports of Adverse Events Associated with Use of Novel Psychoactive Substances, 2017-2020: A Review

An important role of modern forensic and clinical toxicologists is to monitor the adverse events of novel psychoactive substances (NPS). Following a prior review from 2013 to 2016, this critical literature review analyzes and evaluates published case reports for NPS from January 2017 through December 2020. The primary objective of this study is to assist in the assessment and interpretation of these cases as well as provide references for confirmation methods. Chemistry, pharmacology, adverse events and user profiles (e.g., polypharmacy) for NPS are provided including case history, clinical symptoms, autopsy findings and analytical results. Literature reviews were performed in PubMed and Google Scholar for publications using search terms such as NPS specific names, general terms (e.g., ‘designer drugs’ and ‘novel psychoactive substances’), drug classes (e.g., ‘designer stimulants’) and outcome-based terms (e.g., ‘overdose’ and ‘death’). Government and website drug surveillance databases and abstracts published by professional forensic science organizations were also searched. Toxicological data and detailed case information were extracted, tabulated, analyzed and organized by drug category. Case reports included overdose fatalities (378 cases), clinical treatment and hospitalization (771 cases) and driving under the influence of drugs (170 cases) for a total of 1,319 cases providing details of adverse events associated with NPS. Confirmed adverse events with associated toxidromes of more than 60 NPS were reported including synthetic cannabinoid, NPS stimulant, NPS hallucinogen, NPS benzodiazepine and NPS opioid cases. Fifty of these NPS were reported for the first time in January 2017 through December 2020 as compared to the previous 4 years surveyed. This study provides insight and context of case findings described in the literature and in digital government surveillance databases and websites during a recent 4-year period. This review will increase the awareness of adverse events associated with NPS use to better characterize international emerging drug threats.

The First Fatal Intoxication with 3-MeO-PCP in the UK and a Review of the Literature

The phencyclidine derivative 3-Methoxyphencyclidine (3-MeO-PCP) is a potent dissociative hallucinogen. Sought for recreational use as a novel psychoactive substance, it can also induce acute psychological agitation and pathophysiological cardiorespiratory effects. Due to the harms associated with its use, 3-MeO-PCP was added to the 'Green List' of materials covered by the 1971 Convention on Psychotropic Substances as a Schedule II substance by the United Nations Commission on Narcotic Drugs in April 2021. There have been 15 previous reports of fatal intoxications following 3-MeO-PCP use, but only one was attributable to 3-MeO-PCP intoxication alone. In this report we detail the first fatality due to 3-MeO-PCP intoxication to be reported in the UK, along with a review of the surrounding literature. Whilst the blood concentrations associated with 3-MeO-PCP toxicity and fatality remain unclear, by providing details of sample collection and storage conditions this case will aid in future interpretations. Furthermore, this case suggests that 3-MeO-PCP toxicity may be exacerbated by exercise. Users of 3-MeO-PCP should be cautioned against its use as a 'club drug' or in a similar setting where elevations in heart rate, body temperature and blood pressure may occur.

Fatal N-Ethylhexedrone Intoxication

N-Ethylhexedrone [2-(ethyloamino)-1-phenylhexan-1-one; α-ethylaminohexanophenone (NEH)] is one of the most recent synthetic cathinones that appeared on the illegal market in late 2015. The majority of information concerning the model of consumption of NEH and its impact on the body originates only from self-reports from gray literature websites and drug forums. There are only limited data associated with the concentrations of NEH in blood samples available in the literature. This article presents a case of fatal NEH intoxication and a method for the determination of this substance in whole blood. A 21-year-old man without any diagnosed diseases was admitted to the hospital due to disorientation, aggression and finally loss of consciousness. Hyperthermia (>41°C), tachycardia (>160 beats per minute), tachypnea (20 breaths per minute), blood pressure (110/60 mmHg) and acute kidney failure were diagnosed. After a few hours of hospitalization, the patient died. A plastic bag with a white powder was found in his underwear. Analysis of the powder by another laboratory revealed cocaine hydrochloride; however, no cocaine or its metabolites were found in the biological material upon testing in our laboratory. Therefore, re-analysis of the powder was performed, and NEH was identified. Liquid–liquid extraction followed by liquid chromatography-triple quadrupole-mass spectrometry (LC-MS/MS) analysis were used for the determination of NEH in blood. The validation parameters were as follows: calibration range 1–250 ng/mL, accuracy 106.5–109.9%, precision 3.5–6.3%, recovery 90.1–96.9%, limit of detection 0.07 ng/mL and limit of quantification 1 ng/mL. NEH was quantified in the blood at a concentration of 145 ng/mL. Additionally, amphetamine at low concentrations and 11-nor-9-karboksy-Δ9-tetrahydrokannabinol (THC-COOH) were detected.

Our study provided information on the possible lethal concentration and toxidrome that clinicians can observe for NEH-intoxicated patients and can be helpful during the preparation of toxicology analysis reports for a court of law for proper data interpretation.

An updated review on synthetic cathinones

Cathinone, the main psychoactive compound found in the plant Catha edulis Forsk. (khat), is a β-keto analogue of amphetamine, sharing not only the phenethylamine structure, but also the amphetamine-like stimulant effects. Synthetic cathinones are derivatives of the naturally occurring cathinone that largely entered the recreational drug market at the end of 2000s. The former "legal status", impressive marketing strategies and their commercial availability, either in the so-called "smartshops" or via the Internet, prompted their large spread, contributing to their increasing popularity in the following years. As their popularity increased, the risks posed for public health became clear, with several reports of intoxications and deaths involving these substances appearing both in the social media and scientific literature. The regulatory measures introduced thereafter to halt these trending drugs of abuse have proved to be of low impact, as a continuous emergence of new non-controlled derivatives keep appearing to replace those prohibited. Users resort to synthetic cathinones due to their psychostimulant properties but are often unaware of the dangers they may incur when using these substances. Therefore, studies aimed at unveiling the pharmacological and toxicological properties of these substances are imperative, as they will provide increased expertise to the clinicians that face this problem on a daily basis. The present work provides a comprehensive review on history and legal status, chemistry, pharmacokinetics, pharmacodynamics, adverse effects and lethality in humans, as well as on the current knowledge of the neurotoxic mechanisms of synthetic cathinones.

New psychoactive substance cocktail in an intensive care intoxication case elucidated by molecular networking

BACKGROUND

The recreational use of new psychoactive substances (NPS) is increasing worldwide. Among them, the arylcyclohexylamine family including phencyclidine (PCP) and ketamine derivatives is increasing. We report a non-fatal intoxication mainly due to arylcyclohexylamine compounds illustrated by molecular networking (MN).

CASE DETAILS

A 37-year-old man with a history of drug abuse was discovered with several bags labeled as research chemicals around him and traces of powder on his nose. He was rehydrated, intubated, and admitted to the intensive care unit (ICU). Urine and drug were analyzed by liquid chromatography-mass spectrometry for NPS identification. Several NPS were quantified in urine: 3-OH-PCP at 12,085 mg/L, 3-MeO-PCP at 1100 mg/L, 2F-DCK at 147 mg/L, N-ethylhexedrone at 165 mg/L and CMC at 48 mg/L. Using a bioinformatic approach, a molecular network was built to confirm the consumption of powders contained in the bags by comparison with patient's urine.

DISCUSSION

This case illustrates the interest of MN to (i) perform sample-to-sample comparison, (ii) target quantification methods, and (iii) allow proper management to confirm the relevance of the treatment.

A Review of Synthetic Cathinone-Related Fatalities From 2017 to 2020

BACKGROUND

Synthetic cathinones (SCs) are designer analogs of the natural active principle of khat. Since their appearance on the black market in 2003, their popularity has increased annually, and they have become the most seized class of new psychoactive substances reported to the UNODC Early Warning Advisory system. The constant introduction of newly synthesized molecules makes this issue difficult to monitor. The authors reviewed the most recent SC-related fatalities worldwide to highlight new trends of consumption, reporting acute pharmacological and toxicological symptoms, scene investigations, analytical methods, and reported SC concentrations in diverse biological matrices.

METHODS

A literature search was performed using scientific databases such as PubMed, Scopus, Science Direct, Web of Science, and Research Gate to identify relevant scientific publications from 2017 to 2020. In addition, a search was conducted through the EU EWS.

RESULTS

From 2017 to 2020, 31 different SCs were identified in 75 reported fatal intoxications in the literature, alone or in combination with other substances. The most abused SCs were N-ethylpentylone, N-ethylhexedrone, and 4-chloromethcathinone. The EU EWS included less detail on 72 additional SC-related fatalities from 2017 to 2020.

CONCLUSIONS

New SCs continuously replace older natural and synthetic stimulant drugs, making determining the cause of death difficult. Analytical methods and high-performance mass spectrometry instruments are essential to detect the low concentrations of these potent new SCs. Little data are available on the pharmacology of these new drugs; the evaluation of toxicological antemortem and postmortem findings provides critical data on the drug's pharmacology and toxicology and for the interpretation of new SC cases.

Fatal intoxication with U-47700 in combination with other NPS (N-ethylhexedrone, adinazolam, 4-CIC, 4-CMC) confirmed by identification and quantification in autopsy specimens and evidences

Purpose

We present a case of fatal intoxication with U-47700 in combination with other NPS (N-ethylhexedrone, adinazolam, 4-chloro-N-isopropylcathinone (4-CIC), 4-chloromethcathinone (4-CMC) and sertraline) confirmed by identification and quantification in biological materials and evidences found at the scene in 2017 in Poland.

Methods

Blood and urine samples were extracted with ethyl acetate from alkaline medium (pH 9); powders/crystals were diluted with methanol. The analysis was carried out using ultra-high-performance liquid chromatography–tandem mass spectrometry. Validation criteria were evaluated for blood and urine at the concentrations of 10 and 100 ng/mL.

Results

The validation parameters of the method were within acceptable ranges. In the presented case, the determined concentrations of drugs were as follows, in blood: U-47700, 1470 ng/mL; N-ethylhexedrone, 58 ng/mL; adinazolam, 18 ng/mL; 4-CIC, 8.0 ng/mL; 4-CMC, 1.7 ng/mL; in urine: U-47700, 3940 ng/mL; N-ethylhexedrone, 147 ng/mL; adinazolam, 82 ng/mL; 4-CIC, 130 ng/mL; 4-CMC, 417 ng/mL. Sertraline (blood, 89 ng/mL; urine, 32 ng/mL) was also determined in both materials. The same substances were also found in 5 powders/crystals: U-47700 (12% by weight), N-ethylhexedrone (54%), adinazolam (14%), 4-CIC (23%), 4-CMC (26%). After 775 days of storage, biological samples at + 4 °C, the most stable substance was sertraline and the less, synthetic cathinones, especially 4-CIC and 4-CMC.

Conclusions

The described case of fatal intoxication with NPS presented postmortem concentrations of U-47700, 4-CMC, N-ethylhexedrone, adinazolam and 4-CIC for the first time in the literature. The paper also showed stability study of these substances stored at + 4 °C for 775 days.

Pharmacotherapy of Patients Taking New Psychoactive Substances: A Systematic Review and Analysis of Case Reports

Background: In recent years, an increase in the frequency of hospitalizations of patients taking newer and newer psychoactive substances has been observed around the world. Each year, authors publish case reports of patients who consumed previously unknown NPS. Most publications of this type concern the period between 2014 and 2016. However, no publication systematically reviews the pharmacotherapy used in these cases. This study aims to review the case reports of patients taking NPS published between 2010 and 2019, as well as analyzing the pharmacotherapy used. Methods: We searched the Thomson (Web of Knowledge), PubMed/Medline, Science Direct, Scopus and Google Scholar databases. The search was performed using all possible combinations of the term "case report" describing the use of NPS, also referred to as designer medications, internet medications, research chemicals and herbal highs. Results: We analyzed 51 case reports on the intake of various types of NPS. Most of them (p < 0.001) concerned the use of synthetic cannabinoids (41.2%) and cathinones (31.4%). The pharmacotherapy applied primarily (p < 0.001) consisted of administering benzodiazepines to patients (62.7%), most of whom took only this group of medications (25.5%), followed by groups receiving benzodiazepines combined with neuroleptics (15.7%) and muscle relaxants (11.8%). Opioids were administered primarily to patients taking synthetic opioids (p < 0.001). Of the 5 cases of deaths from NPS reported in the literature, three relate specifically to the synthetic opioid MT-45. The later the time period, the more medications patients were administered (p = 0.02). Conclusion: In the pharmacotherapy for NPS poisoning, one should focus primarily on combating psychomotor agitation.

Screening of 104 New Psychoactive Substances (NPS) and Other Drugs of Abuse in Oral Fluid by LC–MS-MS

New psychoactive substances (NPS) are a major public health problem, primarily due to the increased number of acute poisoning cases. Detection of these substances is a challenge. The aim of this research was to develop and validate a sensitive screening method for 104 drugs of abuse, including synthetic cannabinoids, synthetic cathinones, fentanyl analogues, phenethylamines and other abused psychoactive compounds (i.e., THC, MDMA, LSD and their metabolites) in oral fluid by liquid chromatography–tandem mass spectrometry (LC–MS-MS). The Quantisal™ oral fluid device was used to collect oral fluid samples. The oral fluid–elution buffer mixture (500-μL sample) was extracted with t-butyl methyl ether, and chromatographic separation was performed on a Raptor™ biphenyl column (100 × 2.1 mm ID, 2.7 μm), with a total run time of 13.5 min. Limits of detection were established at three concentrations (0.05, 0.1 or 1 ng/mL) for most analytes, except for acetyl norfentanyl and mescaline (5 ng/mL). Matrix effects were generally &lt;20% and overall extraction recoveries &gt;60%. The highest matrix effect was observed within the synthetic cannabinoid group (PB22, −55.5%). Lower recoveries were observed for 2C-T (47.2%) and JWH-175 (58.7%). Recoveries from the Quantisal™ device were also evaluated for all analytes (56.7–127%), with lower recoveries noted for 25I-NBOMe, valerylfentanyl and mCPP (56.7, 63.0 and 69.9%, respectively). Drug stability in oral fluid was evaluated at 15, 60 and 90 days and at 25, 4 and −20°C. As expected, greater stability was observed when samples were stored at −20°C, but even when frozen, some NPS (e.g., synthetic cannabinoids) showed more than 20% degradation. The method was successfully applied to the analysis of seven authentic oral fluid samples positive for 17 different analytes. The method achieved good sensitivity and simultaneous detection of a wide range of NPS.

In vitro and in vivo metabolism and detection of 3-HO-PCP, a synthetic phencyclidine, in human samples and pooled human hepatocytes using high resolution mass spectrometry

The new psychoactive substance (NPS) 3-HO-PCP, a phencyclidine (PCP) analog, was detected in a law enforcement seizure and in forensic samples in Denmark. Compared with PCP, 3-HO-PCP is known to be a more potent dissociative NPS, but no toxicokinetic investigations of 3-HO-PCP are yet available. Therefore, 3-HO-PCP was quantified in in vivo samples, and the following were investigated: plasma protein binding, in vitro and in vivo metabolites, and metabolic targets. All samples were separated by liquid chromatography and analyzed by mass spectrometry. The unbound fraction in plasma was determined as 0.72 ± 0.09. After in vitro incubation with pooled human hepatocytes, four metabolites were identified: a piperidine-hydroxyl-and piperidine ring opened N-dealkyl-COOH metabolite, and O-glucuronidated- and O-sulfate-conjugated metabolites. In vivo, depending on the sample and sample preparation, fewer metabolites were detected, as the O-sulfate-conjugated metabolite was not detected. The N-dealkylated-COOH metabolite was the main metabolite in the deconjugated urine sample. in vivo analytical targets in blood and brain samples were 3-HO-PCP and the O-glucuronidated metabolite, with 3-HO-PCP having the highest relative signal intensity. The drug levels of 3-HO-PCP quantified in blood were 0.013 and 0.095 mg/kg in a living and a deceased subject, respectively. The 3-HO-PCP concentrations in deconjugated urine in a sample from a living subject and in post-mortem brain were 7.8 and 0.16 mg/kg, respectively. The post mortem results showed a 1.5-fold higher concentration of 3-HO-PCP in the brain tissue than in the post mortem blood sample.

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 (GABA_A) or GABA_B 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-HT_2A) 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.