Intoxication by 3-MeO-PCP and O-desmethyltramadol: an unusual NPS mix.

Over the past few years, the new psychoactive substances' phenomenon has been continuously studied. Its dynamic context is characterized by a broad diversity of substances, including several groups, such as synthetic cathinones, synthetic opiates, and synthetic cannabinoids. However, and due both to this diversity and to the low number of detected cases, information on intoxication reports is always important, in order to understand their biological mechanisms. In this case, a male individual was found unresponsive, with some different powders and paraphernalia near him. After toxicological analysis to the powders, paraphernalia, and whole blood samples, five different compounds were identified. From these, two of them (3-MeO-PCP and o-desmethyltramadol) were identified and quantitated in the whole blood sample. The obtained results suggested that death was due to the presence and action of these two substances, in what may be considered an unusual mix of NPS. This case highlights the value of evaluating all the traces found in the scene investigation and the need of sending all the paraphernalia found for toxicological examination, together with all the possible information obtained on the scene, namely by relatives or witnesses. On the other hand, this case shows the significance of broad-spectrum analytical methods, in order to detect and identify, as specifically as possible, eventual substances present and used by victims.

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. While 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.

The Abuse Potential of Novel Synthetic Phencyclidine Derivative 1-(1-(4-Fluorophenyl)Cyclohexyl)Piperidine (4'-F-PCP) in Rodents.

The dissociative anesthetic phencyclidine (PCP) and PCP derivatives, including 4'-F-PCP, are illegally sold and abused worldwide for recreational and non-medical uses. The psychopharmacological properties and abuse potential of 4'-F-PCP have not been fully characterized. In this study, we evaluated the psychomotor, rewarding, and reinforcing properties of 4'-F-PCP using the open-field test, conditioned place preference (CPP), and self-administration paradigms in rodents. Using Western immunoblotting, we also investigated the expression of dopamine (DA)-related proteins and DA-receptor-mediated downstream signaling cascades in the nucleus accumbens (NAc) of 4'-F-PCP-self-administering rats. Intraperitoneal administration of 10 mg/kg 4'-F-PCP significantly increased locomotor and rearing activities and increased CPP in mice. Intravenous administration of 1.0 mg/kg/infusion of 4'-F-PCP significantly enhanced self-administration during a 2 h session under fixed ratio schedules, showed a higher breakpoint during a 6 h session under progressive ratio schedules of reinforcement, and significantly altered the expression of DA transporter and DA D1 receptor in the NAc of rats self-administering 1.0 mg/kg 4'-F-PCP. Additionally, the expression of phosphorylated (p) ERK, pCREB, c-Fos, and FosB/ΔFosB in the NAc was significantly enhanced by 1.0 mg/kg 4'-F-PCP self-administration. Taken together, these findings suggest that 4'-F-PCP has a high potential for abuse, given its robust psychomotor, rewarding, and reinforcing properties via activation of DAergic neurotransmission and the downstream signaling pathways in the NAc.

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.

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

INTRODUCTION: 3-Hydroxyphencyclidine (3-HO-PCP) is a new psychoactive substance (NPS) and a hydroxy derivative of phencyclidine (PCP), and N-ethylhexedrone (Hexen) is a synthetic cathinone. We describe an analytically confirmed case of acute toxicity related to the use of both 3-hydroxyphencyclidine and N-ethylhexedrone. CASE REPORT: A 56-year-old male was brought to the Emergency Department by ambulance with hyperthermia (39.9 °C), sinus tachycardia (150 beats per minute), reduced consciousness, ocular clonus, and vertical nystagmus. He was treated with cooled intravenous (IV) fluids and IV benzodiazepines. Following 1 hour of treatment, his temperature fell to 37.7 °C, he developed rhabdomyolysis (creatine kinase peaked at 5999 IU (normal range < 229 IU)): he was managed with supportive measures and was discharged after 25 hours. The patient admitted regular use of Hexen and recent use of 3-HO-PCP. Analysis of urine and serum identified 3-hydroxyphencyclidine and metabolites, N-ethylhexedrone and metabolites, and clephedrone and metabolites. DISCUSSION: This is a case of analytically confirmed toxicity to 3-HO-PCP and N-ethylhexedrone. The acute toxicity reported in this patient is consistent with the use of 3-HO-PCP, but there were sympathomimetic and serotonergic features potentially consistent with the cathinone N-ethylhexedrone. The description of the acute toxicity of NPS, such as these, is vital to aid medical toxicologists and emergency medicine physicians treating patients who use them.

4-MeO-PCP and 3-MeO-PCMo, new dissociative drugs, produce rewarding and reinforcing effects through activation of mesolimbic dopamine pathway and alteration of accumbal CREB, deltaFosB, and BDNF levels.

RATIONALE: A high number of synthetic dissociative drugs continue to be available through online stores, leading to their misuse. Recent inclusions in this category are 4-MeO-PCP and 3-MeO-PCMo, analogs of phencyclidine. Although the dissociative effects of these drugs and their recreational use have been reported, no studies have investigated their abuse potential. OBJECTIVES: To examine their rewarding and reinforcing effects and explore the mechanistic correlations. METHODS: We used conditioned place preference (CPP), self-administration, and locomotor sensitization tests to assess the rewarding and reinforcing effects of the drugs. We explored their mechanism of action by pretreating dopamine receptor (DR) D1 antagonist SCH23390 and DRD2 antagonist haloperidol during CPP test and investigated the effects of 4-MeO-PCP and 3-MeO-PCMo on dopamine-related proteins in the ventral tegmental area and nucleus accumbens. We also measured the levels of dopamine, phosphorylated cyclic-AMP response element-binding (p-CREB) protein, deltaFosB, and brain-derived neurotrophic factor (BDNF) in the nucleus accumbens. Additionally, we examined the effects of both drugs on brain wave activity using electroencephalography. RESULTS: While both 4-MeO-PCP and 3-MeO-PCMo induced CPP and self-administration, only 4-MeO-PCP elicited locomotor sensitization. SCH23390 and haloperidol inhibited the acquisition of drug CPP. 4-MeO-PCP and 3-MeO-PCMo altered the levels of tyrosine hydroxylase, DRD1, DRD2, and dopamine, as well as that of p-CREB, deltaFosB, and BDNF. All drugs increased the delta and gamma wave activity, whereas pretreatment with SCH23390 and haloperidol inhibited it. CONCLUSION: Our results indicate that 4-MeO-PCP and 3-MeO-PCMo induce rewarding and reinforcing effects that are probably mediated by the mesolimbic dopamine system, suggesting an abuse liability in humans.

Intoxication with 3-MeO-PCP alone: A case report and literature review.

RATIONALE: 3-Methoxyphencyclidine (3-MeO-PCP) is a new psychoactive substance derived from phencyclidine. Although it can lead to severe intoxications, the main manifestations and optimal management have not been well characterized. Here, we report 2 cases of 3-MeO-PCP intoxication in the same patient, and summarize the manifestations of this intoxication reported in literature. PATIENT CONCERNS: A 17-year-old male purchased a bag of 3-MeO-PCP on the Internet but took an oral dose (200 mg) that corresponds to the less active isomer 4-MeO-PCP. He developed high blood pressure (158/131 mm Hg), tachycardia (100 bpm), and neurological manifestations (confusion, hypertonia, nystagmus, and then agitation). A maculopapular rash appeared, although this may have been related to the administration of midazolam. Hyperlactatemia (2.6 mmol/L) was the main laboratory finding. Seven days later, he returned to the emergency department after sniffing 50 mg of 3-MeO-PCP. High blood pressure, tachycardia, and neurological manifestations (psychomotor impairment and dysarthria) were present but less severe than after the first intoxication. DIAGNOSIS: In the first intoxication, the blood and urine 3-MeO-PCP concentrations were, respectively, 71.1 ng/mL and 706.9 ng/mL. Conventional toxicity tests were all negative. In the second intoxication, biological samples were not available. INTERVENTIONS: In the first intoxication, treatment consisted of intravenous hydration and midazolam. The patient was transferred to an intensive care unit for monitoring. After the second intoxication, he was monitored for 12 hours. OUTCOMES: The patient's condition improved quickly in both cases. LESSONS: These cases provide additional information on the manifestations of 3-MeO-PCP intoxication. These manifestations are mainly cardiovascular (high blood pressure, tachycardia) and neurological. The fact that second (50 mg) intoxication was less severe than the first (200 mg) is suggestive of a dose-effect relationship for 3-MeO-PCP. The first case also emphasizes the risk of dosing errors caused by the similarity between the names "3-MeO-PCP" and "4-MeO-PCP."

Detectability of Dissociative Psychoactive Substances in Urine by Five Commercial Phencyclidine Immunoassays.

Methoxetamine (MXE) and the arylcyclohexylamines 3-methoxy-PCP (3-MeO-PCP) and 4-methoxy-PCP (4-MeO-PCP) are substituted analogs of the dissociative psychoactive substances ketamine and phencyclidine (PCP), respectively. They have emerged on the new psychoactive substances (NPS) market as legal alternatives to these classically banned dissociatives. Little data has been published regarding the cross-reactivity of these NPS in PCP immunoassays (IAs). The aim of this work was to explore the possibilities of detecting 3-MeO-PCP, 4-MeO-PCP, MXE and ketamine in commercial IAs for PCP. The cross-reactivity study was performed in five different PCP IAs using urine-free, spiked samples and urine samples obtained from two 3-MeO-PCP overdose cases. 3-MeO-PCP and 4-MeO-PCP showed cross-reactivity (ranging from 1-143%) in all PCP IAs evaluated. MXE only showed very weak cross-reactivity (ranged from 0.04 to 0.25%) and ketamine was not detected in any PCP IA evaluated. Urine samples from the two overdose cases were positive for PCP in all IAs evaluated. The commercial PCP IAs evaluated exhibited utility as rapid, preliminary screening techniques for 3-MeO-PCP and 4-MeO-PCP, but not for ketamine. The low reactivity of MXE limits its detectability in the PCP IAs evaluated.

The risk of emerging new psychoactive substances: The first fatal 3-MeO-PCP intoxication in The Netherlands.

Structural analogs of classic drugs, also called designer drugs, are a booming market due to the easy accessibility on the internet and their legal status. One of those 'legal highs' is an analog of phencyclidine, namely 3-methoxyphencyclidine (3-MeO-PCP). Very few fatalities have been reported where 3-MeO-PCP contributed to the death of an individual. We present the first fatal case in the Netherlands and one of the few worldwide. Postmortem biological samples and the presumed abused unknown substance, sold as ant poison, were obtained. 3-MeO-PCP was detected, and the resulting concentration was 152 µg/l in whole blood. The presumed taken unknown sample was identified as 3-MeO-PCP and thus linked to the victim. The cause of death was a combination of 3-MeO-PCP, amphetamine, and alcohol. Improved diagnostic skills are necessary to face these emerging novel psychoactive substances also in light of public health and social risks.

Metabolites to parent 3-MeO-PCP ratio in human urine collected in two fatal cases.

In this article, two fatal cases related to the use of 3-methoxyphencyclidine (3-MeO-PCP) are described. This compound is a new psychoactive substance that belongs to the phencyclidine family. In the recent period, this dissociative drug has gained interest because of its proposal as a legally available alternative to phencyclidine in some countries. The scientific literature related to 3-MeO-PCP is very poor. Using standard ultra-performance liquid chromatography-mass spectrometry and ultra-performance liquid chromatography-tandem mass spectrometry, the authors focused on the detection of 3-MeO-PCP and its metabolites in human urine. 3-MeO-PCP metabolism was studied in vitro after drug incubation with human liver microsomes and the identified metabolites were investigated in the urine of the two forensic cases. 3-MeO-PCP metabolites, including O-demethyl-3-MeO-PCP, piperidine-hydroxy-3-MeO-PCP, O-demethyl-piperidine-di-hydroxy-3-MeO-PCP and piperidine-di-hydroxy-3-MeO-PCP, were detectable in the urine from both cases and the ratio between metabolites and parent 3-MeO-PCP, always lower than 1, were calculated to estimate the proportionality of metabolites. At this stage, one can conclude that testing for 3-MeO-PCP metabolites does not increase the window of detection of the drug.

Application of a molecular networking approach for clinical and forensic toxicology exemplified in three cases involving 3-MeO-PCP, doxylamine, and chlormequat.

Untargeted toxicological screening is an analytical challenge, given the high number of molecules and metabolites to be detected and the constant appearance of new psychoactive substances (NPS). The combination of liquid chromatography with high-resolution tandem mass spectrometry (HRMS/MS) in a data-dependent acquisition mode generates a large volume of high quality spectral data. Commercial software for processing MS data acquired during untargeted screening experiments usually compare measured features (mass, retention time, and fragmentation spectra) against a predefined list of analytes. However, there is a lack of tools for visualizing and organizing MS data of unknown compounds. Here, we applied molecular networking to untargeted toxicological screening. This bioinformatic tool allows the exploration and organization of MS/MS data without prior knowledge of the sample's chemical composition. The organization of spectral data is based on spectral similarity. Hence, important information can be obtained even before the annotation step. The link established between molecules enables the propagation of structural information. We applied this approach to three clinical and forensic cases with various matrices: (a) blood and a syringe content in a forensic case of death by self-injection, (b) hair segments in a case of drug-facilitated assault, and (c) urine and blood samples in a case of 3-methoxyphencyclidine intoxication. Data preprocessing with MZmine allows sample-to-sample comparison and generation of multisample molecular networks. Our present study shows that molecular networking can be a useful complement to conventional approaches for untargeted screening interpretation, for example for xenobiotics identification or NPS metabolism elucidation.

Murdered while under the influence of 3-MeO-PCP.

The abuse of new psychoactive substances (NPS) has been dramatically increasing all around the world since the late 2000s. The availability of hundreds of NPS in the past decade is challenging for both public health and global drug policies. A 39-year-old woman, known as a multidrug addict, was murdered by her partner by ligature strangulation. A comprehensive toxicological screening by gas chromatography and ultra-high performance liquid chromatography with tandem mass spectrometry revealed the simultaneous presence of ethanol (1.37 g/L), diazepam (157 ng/mL) and nordiazepam (204 ng/mL), cocaine (25 ng/mL) and benzoylecgonine (544 ng/mL), and (3-methoxy-(1-(1-phenylcyclohexyl)piperidine) or 3-MeO-PCP, a dissociative hallucinogen anesthetic drug. Concentrations of 3-MeO-PCP were 63, 64, and 94 ng/mL in femoral blood, bile, and urine, respectively. Hair tested also positive for 3-MeO-PCP on 3 × 2-cm segments at 731, 893, and 846 pg/mg, indicating long-term abuse of the drug. This seems to be the first ever reported hair concentrations. Major impairment of the victim, including visual hallucinations and alteration of behavior, was attributed to the mixture of all the drugs, with a major contribution of 3-MeO-PCP. The toxicological findings were compared to the few reports available in the medical literature.

Syntheses, analytical and pharmacological characterizations of the 'legal high' 4-[1-(3-methoxyphenyl)cyclohexyl]morpholine (3-MeO-PCMo) and analogues.

New psychoactive substances (NPS) are commonly referred to as 'research chemicals', 'designer drugs' or 'legal highs'. One NPS class is represented by dissociative anesthetics, which include analogues of the arylcyclohexylamine phencyclidine (PCP), ketamine and diphenidine. A recent addition to the NPS market was 4-[1-(3-methoxyphenyl)cyclohexyl]morpholine (3-MeO-PCMo), a morpholine analogue of 3-MeO-PCP. Although suspected to have dissociative effects in users, information about its pharmacological profile is not available. From clinical and forensic perspectives, detailed analytical data are needed for identification, especially when facing the presence of positional isomers, as these are frequently unavailable commercially. This study presents the analytical and pharmacological characterization of 3-MeO-PCMo along with five additional analogues, namely the 2- and 4-MeO-PCMo isomers, 3,4-methylenedioxy-PCMo (3,4-MD-PCMo), 3-Me-PCMo and PCMo. All six arylcyclohexylmorpholines were synthesized and characterized using chromatographic, mass spectrometric and spectroscopic techniques. The three positional isomers could be differentiated and the identity of 3-MeO-PCMo obtained from an internet vendor was verified. All six compounds were also evaluated for affinity at 46 central nervous system receptors including the N-methyl-d-aspartate receptor (NMDAR), an important target for dissociative anesthetics such as PCP and ketamine. In vitro binding studies using (+)-[3-3 H]-MK-801 in rat forebrain preparations revealed moderate affinity for NMDAR in the rank order of 3-Me >3-MeO > PCMo >3,4-MD > 2-MeO > 4-MeO-PCMo. 3-MeO-PCMo was found to have moderate affinity for NMDAR comparable to that of ketamine, and had an approximate 12-fold lower affinity than PCP. These results support the anecdotal reports of dissociative effects from 3-MeO-PCMo in humans.

Two Fatal Intoxications Involving 3-Methoxyphencyclidine.

3- and 4-methoxyphencyclidine (3-MeO-PCP, 4-MeO-PCP), structural analogs of phencyclidine (PCP), were among the first legal PCP alternatives to show up on the novel psychoactive substances (NPS) market in Europe in the 2000s. Their structural similarities to PCP and ketamine likely contribute to their demonstrated dissociative anesthetic effects. Limited information exists in the literature about toxic and lethal concentrations of these drugs in biological samples. This case report presents the first two death cases in Washington State in which 3-MeO-PCP was identified. Alkaline drug screen analysis by gas chromatography-mass spectrometry (GC-MS) revealed a peak with a retention time similar to PCP and base peak of m/z 230. Certified reference materials for 3-and 4-MeO-PCP were obtained and the isomers were able to be distinguished based on different retention times and mass spectra. A quantitative GC-MS method was developed and validated for casework, utilizing a dynamic range of 10-1,000 ng/mL and a limit of detection of 1 ng/mL. Postmortem (peripheral/central) blood samples were analyzed using this method and the resulting concentrations were 0.63 and 3.2 mg/L of 3-MeO-PCP. Methamphetamine (0.11 mg/L) was additionally detected in the blood of one of the decedents; while the second decedent was additionally positive for ethanol (0.047 g/100 mL), bupropion (1.8 mg/L), delorazepam, paroxetine and mitragynine. The results presented in this case report are higher than previously reported concentrations in fatal cases, but the presence of polysubstance abuse is consistent with previously reported NPS intoxications. Both of these individuals were in drug rehabilitation facilities prior to their deaths; however, users continue to be drawn to 3-MeO-PCP due to its dissociative effects and its accessibility on the internet.

A non-fatal intoxication and seven deaths involving the dissociative drug 3-MeO-PCP.

INTRODUCTION: 3-methoxyphencyclidine (3-MeO-PCP) appeared on the illicit drug market in 2011 and is an analogue of phencyclidine, which exhibits anesthetic, analgesic and hallucinogenic properties. In this paper, we report data from a non-fatal intoxication and seven deaths involving 3-MeO-PCP in Sweden during the period March 2014 until June 2016. CASE DESCRIPTIONS: The non-fatal intoxication case, a 19-year-old male with drug problems and a medical history of depression, was found awake but tachycardic, hypertensive, tachypnoeic and catatonic at home. After being hospitalized, his condition worsened as he developed a fever and lactic acidosis concomitant with psychomotor agitation and hallucinations. After 22h of intensive care, the patient had made a complete recovery. During his hospitalization, a total of four blood samples were collected at different time points. The seven autopsy cases, six males and one female, were all in their twenties to thirties with psychiatric problems and/or an ongoing drug abuse. METHODS: 3-MeO-PCP was identified with liquid chromatography (LC)/time-of-flight technology and quantified using LC-tandem mass spectrometry. RESULTS: In the clinical case, the concentration of 3-MeO-PCP was 0.14µg/g at admission, 0.08µg/g 2.5h after admission, 0.06µg/g 5h after admission and 0.04µg/g 17h after admission. The half-life of 3-MeO-PCP was estimated to 11h. In the autopsy cases, femoral blood concentrations ranged from 0.05µg/g to 0.38µg/g. 3-MeO-PCP was the sole finding in the case with the highest concentration and the cause of death was established as intoxication with 3-MeO-PCP. In the remaining six autopsy cases, other medications and drugs of abuse were present as well. CONCLUSION: Despite being scheduled in January 2015, 3-MeO-PCP continues to be abused in Sweden. Exposure to 3-MeO-PCP may cause severe adverse events and even death, especially if the user does not receive life-supporting treatment.

Two Cases of Non-fatal Intoxication with a Novel Street Hallucinogen: 3-Methoxy-Phencyclidine.

3-Methoxy-phencyclidine (3-MeO-PCP) is a structural derivative of the dissociative hallucinogen phencyclidine (PCP). Although PCP toxicity is well documented, little is known about this new psychoactive substance despite being available on the black market even in central Europe. The objective of this case report is to present clinical and laboratory data of analytically confirmed non-fatal intoxication of two subjects with 3-MeO-PCP. A preliminary assessment of potential metabolites excreted into urine was enabled using the liquid chromatography high resolution mass spectrometric method.

3-MeO-PCP intoxication in two young men: First in vivo detection in Italy.

3-MeO-PCP or 3-methoxyphencyclidine is a derivative of phencyclidine. It acts as a dissociative anesthetic and it has allegedly hallucinogenic and sedative effects. There are almost no documented intoxication cases and references about its pharmacology and toxicity in literature. This study presents two concomitant intoxication cases due to consumption of 3-MeO-PCP and alcohol. A 19 (A) and a 21 years old (B) men were brought to Santa Maria Nuova Hospital in a comatose state (Glasgow score 3). They showed respiratory acidosis, right anisocoria with mydriatic pupils and hypothermia. Toxicological screening was negative. They were intubated for 7-8h. Almost 24h after hospitalization they were still in a delirious and agitated status. The subjects declared a high alcohol consumption and ingestion of unknown pills. Blood and urine were collected upon their arrival to the Emergency Department and sent to our Forensic Toxicology Division. Blood alcohol content was 2.0g/L for subject A and 1,7g/L for subject B. The specimens were analyzed by means of GC-MS, revealing the presence of 3-MeO-PCP. A confirmation and quantification was carried out by means of a new and fully validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for new psychoactive substances (NPS) detection. The analysis was performed adding acetonitrile to the samples, the supernatant was dried and reconstituted with methanol. Mephedrone-D3 was used as internal standard. Acquisition was performed through multiple reaction monitoring (MRM) dynamic mode. The MRM transitions used for quantification of 3-MeO-PCP were: m/z 274→86, 121. 3-MeO-PCP was quantified in all the biological samples at the following concentrations: 350.0 (blood) and 6109.2 (urine) ng/mL for A; 180.1 (blood) and 3003.6 (urine) ng/mL for B. Taking into account the analytical results, we can suppose that the manifested symptoms were due to the consumption of 3-MeO-PCP in synergy with alcohol. Our report is the first case of 3-MeO-PCP intoxication in Italy and one of the few documented all over the world. For this reason, this case represents a significant worrisome alarm about the spread of this substance. Here we want to highlight the importance of having an effective and broad-spectrum analytical method in order to face the NPS issue.

New Psychoactive Substances 3-Methoxyphencyclidine (3-MeO-PCP) and 3-Methoxyrolicyclidine (3-MeO-PCPy): Metabolic Fate Elucidated with Rat Urine and Human Liver Preparations and their Detectability in Urine by GC-MS, "LC-(High Resolution)-MSn" and "LC-(High Resolution)-MS/MS".

BACKGROUND: 3-Methoxyphencyclidine (3-MeO-PCP) and 3-methoxyrolicyclidine (3-MeOPCPy) are two new psychoactive substances (NPS). The aims of the present study were the elucidation of their metabolic fate in rat and pooled human liver microsomes (pHLM), the identification of the cytochrome P450 (CYP) isoenzymes involved, and the detectability using standard urine screening approaches (SUSA) after intake of common users' doses using gas chromatography-mass spectrometry (GC-MS), liquid chromatography-multi-stage mass spectrometry (LC-MSn), and liquid chromatography-high-resolution tandem mass spectrometry (LC-HR-MS/MS). METHODS: For metabolism studies, rat urine samples were treated by solid phase extraction or simple precipitation with or without previous enzymatic conjugate cleavage. After analyses via LC-HR-MSn, the phase I and II metabolites were identified. RESULTS: Both drugs showed multiple aliphatic hydroxylations at the cyclohexyl ring and the heterocyclic ring, single aromatic hydroxylation, carboxylation after ring opening, O-demethylation, and glucuronidation. The transferability from rat to human was investigated by pHLM incubations, where Odemethylation and hydroxylation were observed. The involvement of the individual CYP enzymes in the initial metabolic steps was investigated after single CYP incubations. For 3-MeO-PCP, CYP 2B6 was responsible for aliphatic hydroxylations and CYP 2C19 and CYP 2D6 for O-demethylation. For 3-MeO-PCPy, aliphatic hydroxylation was again catalyzed by CYP 2B6 and O-demethylation by CYP 2C9 and CYP 2D6 Conclusions: As only polymorphically expressed enzymes were involved, pharmacogenomic variations might occur, but clinical data are needed to confirm the relevance. The detectability studies showed that the authors' SUSAs were suitable for monitoring the intake of both drugs using the identified metabolites.

Development of a Specific Substrate-Inhibitor Panel (Liver-on-a-Chip) for Evaluation of Cytochrome P450 Activity.

We developed a cytochrome P450 substrate-inhibitor panel for preclinical in vitro evaluation of drugs in a 3D histotypical microfluidic cell model of human liver (liver-on-a-chip technology). The concentrations of substrates and inhibitors were optimized to ensure reliable detection of the principal metabolites by HPLC-mass-spectroscopy. The selected specific substrate-inhibitor pairs, namely bupropion/2-phenyl-2-(1-piperidinyl)propane) for evaluation of CYP2B6B activity, tolbutamide/sulfaphenazole for CYP2C9, omeprazole/(+)-N-benzylnirvanol for CYP2C19, and testosterone/ketoconazole for CYP3A4, enable reliable evaluation of the drug metabolism pathway. In contrast to animal models characterized by species-specific expression profile and activity of cytochrome P450 isoforms, our in vitro model reflects the metabolism of human hepatocytes in vivo.