Human metabolism of four synthetic benzimidazole opioids: isotonitazene, metonitazene, etodesnitazene, and metodesnitazene.

Following isotonitazene scheduling in 2019, the availability of alternative 2-benzylbenzimidazole opioids (nitazenes) on the global drug market increased, resulting in many fatalities worldwide. Nitazenes are potent µ-opioid receptor agonists with strong narcotic/analgesic effects, and their concentrations in biological matrices are low, making the detection of metabolite biomarkers of consumption crucial to document use in clinical and forensic settings. However, there is little to no data on the metabolism of the most recently available nitazenes, especially desnitro-analogues. The aim of the research was to assess isotonitazene, metonitazene, etodesnitazene, and metodesnitazene human metabolism and identify specific metabolite biomarkers of consumption. The four analogues were incubated with 10-donor-pooled human hepatocytes, and the incubates were analyzed by liquid chromatography-high-resolution tandem mass spectrometry and data mining with Compound Discoverer (Thermo Scientific); the analysis was supported by in silico metabolite predictions with GLORYx open-access software. Metabolites were identified in postmortem blood and/or urine samples from two metonitazene-positive and three etodesnitazene-positive cases following the same workflow, with and without glucuronide hydrolysis in urine, to confirm in vitro results. Twelve, nine, twenty-two, and ten metabolites were identified for isotonitazene, metonitazene, etodesnitazene, and metodesnitazene, respectively. The main transformations were N-deethylation at the N,N-diethylethanamine side chain, O-dealkylation, and further O-glucuronidation. In vitro and autopsy results were consistent, demonstrating the efficacy of the 10-donor-pooled human hepatocyte model to predict human metabolism. We suggest the parent and the corresponding O-dealkyl- and N-deethyl-O-dealkyl metabolites as biomarkers of exposure in urine after glucuronide hydrolysis, and the corresponding N-deethyl metabolite as additional biomarker in blood.

ß'-Phenylfentanyl Metabolism in Primary Human Hepatocyte Incubations: Identification of Potential Biomarkers of Exposure in Clinical and Forensic Toxicology.

From 2014 onwards, illicit fentanyl and analogues have caused numerous intoxications and fatalities worldwide, impacting the demographics of opioid-related overdoses. The identification of cases involving fentanyl analogues is crucial in clinical and forensic settings to treat patients, elucidate intoxications, address drug use disorders and tackle drug trends. However, in analytical toxicology, the concentration of fentanyl analogues in biological matrices is low, making their detection challenging. Therefore, the identification of specific metabolite biomarkers is often required to document consumption. ß'-Phenylfentanyl (N-phenyl-N-[1-(2-phenylethyl)-4-piperidinyl]-benzenepropanamide) is a fentanyl analogue that was first detected in Sweden in 2017 and has recently reemerged onto the American illicit drug market. There is little data available on ß'-phenylfentanyl effects and toxicokinetics and its metabolism is yet to be studied. We aimed to investigate ß'-phenylfentanyl human metabolism to identify potential biomarkers of use. To assist in ß'-phenylfentanyl metabolite identification, a list of putative reactions was generated using in silico predictions with GLORYx freeware. ß'-phenylfentanyl was incubated with cryopreserved 10-donor-pooled human hepatocytes, analyses were performed by liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS-MS) and data were processed using a partially automated targeted/untargeted approach with Compound Discoverer. We identified 26 metabolites produced by N-dealkylation, oxidation, hydroxylation, O-glucuronidation, O-methylation and combinations thereof. We suggest ß'-phenylnorfentanyl (N-phenyl-N-4-piperidinyl-benzenepropanamide) and further metabolites 1-oxo-N-phenyl-N-4-piperidinyl-benzenepropanamide and 1-hydroxy-N-phenyl-N-4-piperidinyl-benzenepropanamide as major biomarkers of ß'-phenylfentanyl use. In silico predictions were mostly wrong, and ß'-phenylfentanyl metabolic fate substantially differed from that of a closely related analogue incubated in the same conditions, highlighting the value of the experimental assessment of new psychoactive substance human metabolism. In vivo data are necessary to confirm the present results. However, the present results may be necessary to help analytical toxicologists identify ß'-phenylfentanyl-positive cases to provide authentic samples.

Human Hepatocyte 4-Acetoxy-N,N-Diisopropyltryptamine Metabolite Profiling by Reversed-Phase Liquid Chromatography Coupled with High-Resolution Tandem Mass Spectrometry.

Tryptamine intoxications and fatalities are increasing, although these novel psychoactive substances (NPS) are not controlled in most countries. There are few data on the metabolic pathways and enzymes involved in tryptamine biotransformation. 4-acetoxy-N,N-diisopropyltryptamine (4-AcO-DiPT) is a synthetic tryptamine related to 4-hydroxy-N,N-diisopropyltryptamine (4-OH-DiPT), 4-acetyloxy-N,N-dipropyltryptamine (4-AcO-DPT), and 4-acetoxy-N,N-dimethyltryptamine (4-AcO-DMT). The aim of this study was to determine the best 4-AcO-DiPT metabolites to identify 4-AcO-DiPT consumption through human hepatocyte metabolism and high-resolution mass spectrometry. 4-AcO-DiPT metabolites were predicted in silico with GLORYx freeware to assist in metabolite identification. 4-AcO-DiPT was incubated with 10-donor-pooled human hepatocytes and sample analysis was performed with reversed-phase liquid chromatography coupled with high-resolution tandem mass spectrometry (LC-HRMS/MS) in positive- and negative-ion modes. Software-assisted LC-HRMS/MS raw data mining was performed. A total of 47 phase I and II metabolites were predicted, and six metabolites were identified after 3 h incubation following ester hydrolysis, O-glucuronidation, O-sulfation, N-oxidation, and N-dealkylation. All second-generation metabolites were derived from the only first-generation metabolite detected after ester hydrolysis (4-OH-DiPT). The metabolite with the second-most-intense signal was 4-OH-iPT-sulfate followed by 4-OH-DiPT-glucuronide, indicating that glucuronidation and sulfation are common in this tryptamine's metabolic pathway. 4-OH-DiPT, 4-OH-iPT, and 4-OH-DiPT-N-oxide are suggested as optimal biomarkers to identify 4-AcO-DiPT consumption.

In silico, in vitro, and in vivo human metabolism of acetazolamide, a carbonic anhydrase inhibitor and common "diuretic and masking agent" in doping.

Acetazolamide (ACZ) is a carbonic anhydrase inhibitor prescribed for the treatment of various pathologies. It is also used in doping and is prohibited in and out of sportive competitions. ACZ was reported not to undergo metabolization. However, the detection of ACZ metabolites may be critical for documenting ACZ use. We aimed to further investigate ACZ metabolic fate in humans. ACZ putative metabolites were generated in silico to assist in metabolite identification. ACZ was incubated with primary human hepatocytes to identify in vitro metabolites (10 µmol/l ACZ and 106 cells/ml), and urine and plasma samples from patients receiving a single 5.0 mg/kg BW PO ACZ dose were analyzed to confirm the results in vivo. Analyses were performed with reversed-phase liquid chromatography and hydrophilic interaction chromatography coupled with high-resolution tandem mass spectrometry (RPLC-HRMS/MS and HILIC-HRMS/MS, respectively). Data were screened with a software-assisted targeted/untargeted workflow. ACZ was quantified in urine samples with creatinine normalization. We identified two metabolites in hepatocyte incubations and three additional metabolites in urine and plasma. Major transformations included cysteine conjugation, glucuronidation, and N-acetylation. All metabolites were detected in plasma, 1.5 h after intake. Major metabolites were detected in urine from 0.25 to 24 h (last collection) after intake. As opposed to the literature, ACZ does undergo metabolization in humans. We propose ACZ, ACZ-Cys, and N-acetyl-ACZ in urine, and ACZ and N-acetyl-ACZ in plasma as specific biomarkers of ACZ intake in doping.

3F-α-pyrrolydinovalerophenone (3F-α-PVP) in vitro human metabolism: Multiple in silico predictions to assist in LC-HRMS/MS analysis and targeted/untargeted data mining.

Synthetic cathinones (SCs) constitute a heterogenous class of new psychoactive substances (NPS), structurally related to cathinone. SCs represent the widest NPS class, second to synthetic cannabinoids, accounting for approximately 160 different analogues with substitution at the phenyl group, the amine group, or the alkyl chain. In 2020, α-pyrrolidonophenone analogues were the most trafficked SCs, and were involved in many fatalities and intoxication cases. In particular, 3F-α-pyrrolidinovalerophenone (3F-α-PVP) was the cause of the highest number of SC-related fatal intoxications in Sweden in 2018. Minor structural modifications are used to avoid legal controls and analytical detection, but may also induce different toxicological profile. Therefore, the identification of specific markers of consumption is essential to discriminate SCs in clinical and forensic toxicology. In this study, we assessed 3F-α-PVP metabolic profile. 3F-α-PVP was incubated with 10-donor-pooled human hepatocytes, LC-HRMS/MS analysis, and software-assisted data mining. This well-established workflow was completed by in silico metabolite predictions using three different freeware. Ten metabolites were identified after 3 h incubation, including hydrogenated, hydroxylated, oxidated, and N-dealkylated metabolites. A total of 51 phase I and II metabolites were predicted, among which 7 were detected in the incubations. We suggest 3F-α-PVP N-butanoic acid, 3F-α-PVP pentanol, and 3F-α-PVP 2-ketopyrrolidinyl-pentanol as specific biomarkers of 3F-α-PVP consumption. This is the first time that an N-ethanoic acid is detected in the metabolic pathway of a pyrrolidine SC, demonstrating the importance of a dual targeted/untargeted data mining strategy.

Fourth Generation of Synthetic Cannabinoid Receptor Agonists: A Review on the Latest Insights.

BACKGROUND: Over the past few years, an emerging number of new psychoactive substances (NPSs) entered the illicit market. NPSs are designed to resemble the effects of classical drugs of abuse, reinforcing their effects and duration. Among the most abused NPS, synthetic cannabinoids are cannabinoid receptor agonists (SCRAs) that mimic the effect of the main psychotropic phytocannabinoid Δ9-tetrahydrocannabinol (THC). METHODS: We herein reviewed the international literature to provide available information on the newest SCRAs generation. RESULTS: Compared to the previous SCRAs generations, the structures of the last generation result in increased affinity for and efficacy at cannabinoid CB1 receptors, which are thought to be mainly responsible for the psychoactive effects of THC and its analogues. Accordingly, these more potent cannabimimetic effects may increase the number of adverse reactions such as neurological disorders (e.g., psychosis, agitation, irritability, paranoia, confusion, and anxiety), psychiatric episodes (e.g., hallucinations, delusions, self-harm), other physical conditions (e.g., tachycardia, hypertension, arrhythmia, chest pain, nausea, vomiting, and fever) and deaths. In the last decade, more than a hundred SCRAs from different chemical classes emerged on the illicit web market. SCRAs have been thoroughly studied: they were physico-chemically characterized, and pharmaco-toxicological characteristics were investigated. The last SCRAs generations include increasingly potent and toxic compounds, posing a potential health threat to consumers. CONCLUSION: From November 2017 to February 2021, at least 20 new "fourth-generation" SCRAs were formally reported to international drug agencies. Our understanding of the neurotoxicity of these compounds is still limited due to the lack of global data, but their potency and their toxicity are likely higher than those of the previous generations.

Biomarkers of 4-hydroxy-N,N-methylpropyltryptamine (4-OH-MPT) intake identified from human hepatocyte incubations.

BACKGROUND: 4-Hydroxy-N,N-methylpropyltryptamine (4-OH-MPT) is a psychedelic tryptamine whose use is regulated in several countries. Due to unspecific effects, consumption can be ascertained only through toxicological analyses. However, the trace amounts of tryptamines are usually challenging to detect in biological samples. 4-OH-MPT metabolism was characterized to identify optimal metabolite markers of intake in clinical/forensic toxicology. RESEARCH DESIGN AND METHODS: 4-OH-MPT was incubated with 10-donor-pooled human hepatocytes to simulate in vivo conditions; samples were analyzed by liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS/MS), and data were processed with Compound Discoverer from Thermo Scientific. LC-HRMS/MS and data mining were supported by in silico metabolite predictions (GLORYx). RESULTS: Three phase I and four phase II metabolites were identified, including N-oxidation and N-demethylation at the alkylamine chain, and O-glucuronidation and sulfation at the hydroxylindole core. CONCLUSIONS: 4-OH-MPT metabolic fate was consistent with the human metabolism of tryptamine analogues: we suggest 4-OH-MPT-N-oxide and 4-hydroxy-N,N-propyltryptamine (4-OH-PT) as metabolite biomarkers of 4-OH-MPT consumption after glucuronide/sulfate hydrolysis in biological samples to improve detection of 4-OH-MPT and phase I metabolites; 4-OH-MPT-glucuronide is suggested as an additional biomarker when hydrolysis is not performed. Further research on the metabolism of structural analogues is necessary to evaluate the specificity of 4-OH-MPT metabolite biomarkers.

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.

Disposition of cannabinoids and their metabolites in serum, oral fluid, sweat patch and urine from healthy individuals treated with pharmaceutical preparations of medical cannabis.

Recently, several countries authorized the use of cannabis flowering tops (dried inflorescences) with a standardized amount of Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD) and their acidic precursors [Δ-9-tetrahydrocannabinolic acid A (THCA-A) and cannabidiolic acid (CBDA)] to treat neurogenic pain. We studied the acute pharmacological effects and disposition of cannabinoids and their metabolites in serum, oral fluid, sweat patch and urine of 13 healthy individuals treated with medical cannabis decoction and oil. Cannabinoids and their metabolites were quantified by ultrahigh performance tandem mass spectrometry. Even if the oil contained a significantly higher amount of THC, the absorption of THC and its metabolites were similar in both herbal preparations. Conversely, whereas oil contained a significantly higher amount of CBD and a lower amount of CBDA, absorption was significantly higher after decoction intake. Only cannabinoids present in both herbal preparations (THC, CBD, THCA-A and CBDA) were found in oral fluid, due to the higher acidity compared with that of serum. THC metabolites urinary excretion was always higher after decoction administration. Decoction induced greater feeling of hunger and drowsiness than oil preparation. Pharmacokinetics of cannabinoids, their precursors and their metabolites in biological fluids of individuals treated with cannabis decoction and oil showed a high interindividual variability. The aqueous preparation was generally better absorbed than the oil, even if it contained a minor amount of THC, THCA-A and CBD.

Pyrrolidinyl Synthetic Cathinones α-PHP and 4F-α-PVP Metabolite Profiling Using Human Hepatocyte Incubations.

For more than ten years, new synthetic cathinones (SCs) mimicking the effects of controlled cocaine-like stimulants have flooded the illegal drug market, causing numerous intoxications and fatalities. There are often no data on the pharmacokinetics of these substances when they first emerge onto the market. However, the detection of SC metabolites is often critical in order to prove consumption in clinical and forensic settings. In this research, the metabolite profile of two pyrrolidinyl SCs, α-pyrrolidinohexaphenone (α-PHP) and 4''-fluoro-α-pyrrolidinovalerophenone (4F-α-PVP), were characterized to identify optimal intake markers. Experiments were conducted using pooled human hepatocyte incubations followed by liquid chromatography-high-resolution tandem mass spectrometry and data-mining software. We suggest α-PHP dihydroxy-pyrrolidinyl, α-PHP hexanol, α-PHP 2'-keto-pyrrolidinyl-hexanol, and α-PHP 2'-keto-pyrrolidinyl as markers of α-PHP use, and 4F-α-PVP dihydroxy-pyrrolidinyl, 4F-α-PVP hexanol, 4F-α-PVP 2'-keto-pyrrolidinyl-hexanol, and 4F-α-PVP 2'-keto-pyrrolidinyl as markers of 4F-α-PVP use. These results represent the first data available on 4F-α-PVP metabolism. The metabolic fate of α-PHP was previously studied using human liver microsomes and urine samples from α-PHP users. We identified an additional major metabolite (α-PHP dihydroxy-pyrrolidinyl) that might be crucial for documenting exposure to α-PHP. Further experiments with suitable analytical standards, which are yet to be synthesized, and authentic specimens should be conducted to confirm these results.

Monitoring Perinatal Exposure to Cannabis and Synthetic Cannabinoids.

PURPOSE: Drug use during pregnancy is a critical global challenge, capable of severe impacts on neonatal development. However, the consumption of cannabis and synthetic cannabinoids is on the rise in pregnant women. Obstetric complications with increased risks of miscarriage, fetal growth restriction, and brain development impairment have been associated with perinatal cannabis exposure, but data on synthetic cannabinoid use during pregnancy are limited. METHODS: We reviewed studies that investigated the risks associated with cannabis and synthetic cannabinoid use and those that reported the concentrations of cannabinoids and synthetic cannabinoids in maternal (breast milk) and neonatal (placenta, umbilical cord, meconium, and hair) matrices during human pregnancy. A MEDLINE and EMBASE literature search to identify all relevant articles published in English from January 1998 to April 2019 was performed. RESULTS: Cannabis use during pregnancy is associated with increased risks of adverse obstetrical outcomes, although neurobehavioral effects are still unclear. Analyses of cannabinoids in meconium are well documented, but further research on other unconventional matrices is needed. Adverse effects due to perinatal synthetic cannabinoid exposure are still unknown, and analytical data are scarce. CONCLUSIONS: Awareness of the hazards of drug use during pregnancy should be improved to encourage health care providers to urge pregnant women to abstain from cannabis and, if cannabis-dependent, seek treatment. Moreover, substances used throughout pregnancy should be monitored as a deterrent to cannabis use, and potential cannabis-dependent women should be identified, so as to limit cannabis-fetal exposure during gestation, and provided appropriate treatment.

Δ9-Tetrahydrocannabinol and Cannabidiol Time Courses in the Sera of "Light Cannabis" Smokers: Discriminating Light Cannabis Use from Illegal and Medical Cannabis Use.

BACKGROUND: Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) time courses in serum and physiological and behavioral effects associated with smoking 1 or 4 "light cannabis" cigarettes were studied. Biomarkers to differentiate light cannabis versus illegal and medical cannabis use were also investigated. METHODS: Sera were obtained at different times from 6 healthy light cannabis consumers and 6 individuals who smoked 1 and 4 cigarettes, within 4 hours through a liquid-liquid method and analyzed by liquid chromatography-tandem mass spectrometry. RESULTS: In serum, minimal THC concentration was observed after a single cigarette smoke, while repeated smoking increased it by 1 order of magnitude. CBD concentrations were higher, but did not increase linearly, probably because it does not preferentially volatilize compared with THC. The highest THC and CBD concentrations were observed 0.5 hours after the start of the smoking of 1 cigarette. Serum THC ranged from 2.7 to 5.9 ng/mL, while serum CBD varied from 5.7 to 48.2 ng/mL. Similarly, the highest THC and CBD concentrations were observed 0.5 hours after the smoking of 4 cigarettes. Specifically, the ranges were THC: 11.0-21.8 ng/mL and CBD: 19.4-35.3 ng/mL. In both cases, the mean THC/CBD concentration ratio ranged from 0.2 to 0.9. There were no significant changes in blood pressure, heart rate, and body temperature, but participants who smoked 4 cigarettes experienced severe drowsiness. CONCLUSIONS: THC and CBD time courses in the sera of light cannabis smokers were similar to those previously observed in oral fluid and blood. Serum THC/CBD concentration ratio not higher than the mean value of 0.9 might be a useful biomarker to identify use of light cannabis versus that of illegal THC cannabis (where THC/CBD concentration ratios are generally greater than 10) or versus that of medical cannabis (where ratios are greater than 1). Consumers should be advised of possible drowsiness after he repeated smoking of light cannabis cigarettes.

Monitoring Prenatal Exposure to Buprenorphine and Methadone.

PURPOSE: Buprenorphine and methadone are international gold standards for managing opioid use disorders. Although they are efficacious in treating opioid dependence, buprenorphine and methadone present risks, especially during pregnancy, causing neonatal abstinence syndrome and adverse obstetrical outcomes. Buprenorphine and methadone are also abused during pregnancy, and identifying their use is important to limit unprescribed prenatal exposure. Previous studies have suggested that concentrations of buprenorphine, but not methadone markers in unconventional matrices may predict child outcomes, although currently only limited data exist. We reviewed the literature on concentrations of buprenorphine, methadone, and their metabolites in unconventional matrices to improve data interpretation. METHODS: A literature search was conducted using scientific databases (PubMed, Scopus, Web of Science, and reports from international institutions) to review published articles on buprenorphine and methadone monitoring during pregnancy. RESULTS: Buprenorphine and methadone and their metabolites were quantified in the meconium, umbilical cord, placenta, and maternal and neonatal hair. Methadone concentrations in the meconium and hair were typically higher than those in other matrices, although the concentrations in the placenta and umbilical cord were more suitable for predicting neonatal outcomes. Buprenorphine concentrations were lower and required sensitive instrumentation, as measuring buprenorphine glucuronidated metabolites is critical to predict neonatal outcomes. CONCLUSIONS: Unconventional matrices are good alternatives to conventional ones for monitoring drug exposure during pregnancy. However, data are currently scarce on buprenorphine and methadone during pregnancy to accurately interpret their concentrations. Clinical studies should be conducted with larger cohorts, considering confounding factors such as illicit drug co-exposure.

Testing Unconventional Matrices to Monitor for Prenatal Exposure to Heroin, Cocaine, Amphetamines, Synthetic Cathinones, and Synthetic Opioids.

BACKGROUND: The prevalence of drug use during pregnancy continues to increase despite the associated serious adverse obstetrical outcomes, including increased risk of miscarriage, fetal growth restriction, brain development impairment, neonatal abstinence syndrome, preterm delivery, and stillbirths. Monitoring drug use during pregnancy is crucial to limit prenatal exposure and provide suitable obstetrical health care. The authors reviewed published literature reporting the concentrations of common drugs of abuse and new psychoactive substances (NPS), such as synthetic cathinones and synthetic opioids, NPS, and their metabolites using unconventional matrices to identify drug use during pregnancy and improve data interpretation. METHODS: A literature search was performed from 2010 to July 2019 using PubMed, Scopus, Web of Science scientific databases, and reports from international institutions to review recently published articles on heroin, cocaine, amphetamine, methamphetamine, synthetic cathinone, and synthetic opioid monitoring during pregnancy. RESULTS: Meconium has been tested for decades to document prenatal exposure to drugs, but data regarding drug concentrations in amniotic fluid, the placenta, the umbilical cord, and neonatal hair are still lacking. Data on prenatal exposure to NPS are limited. CONCLUSIONS: Maternal hair testing is the most sensitive alternative matrix for identifying drug use during pregnancy, while drug concentrations in the meconium, placenta, and umbilical cord offer the identification of prenatal drug exposure at birth. Adverse developmental outcomes for the infant make it critical to promptly identify maternal drug use to limit fetal exposure or, if determined at birth, to provide resources to the exposed child and family. Alternative matrices offer choices for monitoring and challenge laboratories to deliver highly sensitive and specific analytical methods for detection.

Pharmacotoxicology of Non-fentanyl Derived New Synthetic Opioids.

A class of opioid agonists not structurally related to fentanyl, derived from research publications of pharmaceutical companies or patents within the United States and abroad are contributing to the current opioid epidemic. Novel synthetic opioids (NSOs) created to circumvent drug control laws such as U-47700, U-49900, AH-7921, or MT-45 have no recognized therapeutic use, are clandestinely manufactured and sold on conventional or dark web. We herein provide a review of the pharmacological properties available on most of these substances trying to provide a better knowledge on these compounds, particularly with respect to toxicity and dangerous adverse effects in users. Indeed, these NSOs share not only a great potency of action and receptor affinity with respect to natural or synthetic opiates (e.g., morphine, heroin, and methadone) but also a non-negligible toxicity leading to intoxications and fatalities, posing a serious harm to public health and society.

Maternal Hair and Neonatal Meconium to Assess Gestational Consumption and Prenatal Exposure to Drugs of Abuse and Psychoactive Drugs.

BACKGROUND: In the last two decades, the consumption of drugs of abuse among women of childbearing age has experienced a significant increase and results from analyses of surveys concerning maternal intake of psychoactive prescription drugs during pregnancy indicate that the rates of intake are increasing each year. Analyses of biological matrices such as maternal hair and neonatal meconium have recently been used for assessment of gestational consumption and consequent prenatal exposure to drugs of abuse in high-risk groups of women. METHODS: Maternal hair and neonatal meconium were analyzed by validated chromatographic-mass spectrometric methodologies to disclose the gestational use of drugs of abuse and psychoactive prescription drugs and consequent prenatal exposure in a cohort of 513 mother-newborn dyads at the Sant Joan de Déu Barcelona Hospital, Spain, during 2012-2013. RESULTS: A total of 3.9% women reported drugs of abuse or prescription psychoactive drug consumption at any time during pregnancy. The prevalence of gestational consumption and the consequent prenatal exposure to drugs of abuse (e.g. cannabis, cocaine and MDMA) was 1.2% in maternal hair and 0.4% in meconium; and of psychoactive prescription drugs (e.g. venlafaxine, citalopram, fluoxetine, clomipramine), was 1.7% in maternal hair and 1.2% in meconium. The prevalence of drugs of abuse and prescription psychoactive drug consumption was lower in our specific cohort of Spanish pregnant women than in other cohorts such as those from U.S. or Denmark. CONCLUSION: Analysis of materno-fetal matrices provides a viable alternative to study prenatal exposure to these substances and develop specific social and health intervention recommendations.