Concentrations of drugs determined in blood samples collected from suspected drugged drivers in England and Wales

Fluorodeschloroketamine found as a street drug in drug seizures and drug driving cases in Hong Kong

BACKGROUND

With the decline of the use of ketamine, one of the common drugs of abuse in Hong Kong, detection of ketamine-related analogues in local laboratories has been encountered.

AIM

A brief account of the occurrence of fluorodeschloroketamine (FDCK) in forensic cases is reported through a retrospective study of all drug seizures and driving under the influence of drugs (DUID) cases since its first appearance.

METHODS

Identification of FDCK in drug seizures was achieved through gas chromatography - mass spectrometry (GC-MS) and/or liquid chromatography - diode array detection (LC-DAD) methods while its quantification was performed using gas chromatography - flame ionization detection (GC-FID). For the analysis of blood samples in DUID cases, identification and quantification were performed using LC-MS/MS by monitoring the respective transitions of FDCK and fluorodeschloronorketamine (FDCNK) using ketamine-d4 and norketamine-d4 respectively as internal standards.

RESULTS

Since its first submission in November 2018, a total of 74 drug seizure cases (151 items) and 6 drug driving cases were encountered till December 2019. Drug seizures found with FDCK were physically similar to those of ketamine seizures. The majority of items were detected with FDCK only (103 items, ∼67%) or as a mixture of FDCK with ketamine (42 items, ∼28%). The drug purity detected with either FDCK only or FDCK mixed with ketamine was high which was similar to those purity found in ketamine seizures. The blood drug concentrations of FDCK of the 6 drug driving cases were in the range of <0.002-1.1 μg/mL and other psychoactive drug(s)/metabolite(s) were also identified. Except for one case where the analysis of the metabolite, fluorodeschloronorketamine (FDCNK), was not conducted due to insufficient sample, the FDCK (FDCNK) concentrations in blood found in the 6 cases were <0.002 (0.005), 0.002 (0.002), 0.002 (0.003), 0.02 (0.035), 0.87 (0.44) and 1.1 (not determined) μg/mL.

CONCLUSIONS

With the drug seizures found with FDCK resembled in physical appearance with ketamine seizures, users might likely misuse it as ketamine. Though complicated by other drugs found, it is speculated that the two cases with higher concentration of FDCK found in blood (1.1 and 0.87 μg/mL) might have contributed to the impairment observed.

Mephedrone concentrations in clinical intoxications and fatal cases: a systematic review

BACKGROUND/PURPOSE

Mephedrone, a ring-substituted synthetic cathinone derivative, gained popularity as a recreational drug in the late 2000s. Reports of fatalities related to mephedrone use have emerged with varying concentrations of blood mephedrone upon forensic investigations. This study aims to evaluate the existing literature on mephedrone concentrations in instances of clinical intoxication and fatal cases.

METHODS

We comprehensively searched electronic databases, including Web of Science, PubMed, Embase, and the Cochrane Library, from inception to July 26, 2023. We selected case reports or case series of mephedrone intoxication presented with individual blood mephedrone concentration. Patient demographics, clinical characteristics, blood mephedrone concentrations, and outcomes were extracted for analysis.

RESULTS

77 cases from 14 case reports and 6 case series were identified for review. There were 34 deaths and 43 non-fatal intoxication cases. The median patient's age was 24 years (IQR: 10), and 91.4% were male. Forty-five of the 63 cases (71.4%) were reported with alcohol or other illicit drugs detected. The median blood mephedrone concentration was 0.37 mg/L (IQR: 1.09 mg/L). Death cases were older than non-fatal cases (median = 30 vs. 22 years, p = 0.029). The median blood mephedrone concentration was higher in death cases (1.30 mg/L vs. 0.12 mg/L, p < 0.0001).

CONCLUSIONS

Blood mephedrone concentration in dead patients is approximately 11 times higher than in non-fatal cases. This finding could serve as a stepping stone to the diagnosis of concentrations in clinical poisoning cases and deaths, especially in the treatment of poisoning patients. In more extensive prospective studies, further research is necessary to establish a standardized, real-time available methodology and validate the predictive value of mephedrone concentrations in the prognostic value of mephedrone concentrations.

Ketamine in DUID cases in the greater Cologne area

INTRODUCTION

Ketamine is primarily used as an anaesthetic or for analgesics in medical treatment, but due to its dissociative and hallucinogenic effects, abuse has increased in the past years leading to several drug impaired driving cases.

METHODS

Eight DUID (driving under the influence of drugs) cases involving ketamine from two institutes of legal medicine over a period from January 2021 to January 2023 were evaluated. The cases were compared with regard to psychomotor impairments, adverse effects on driving performance and co-consumption of drugs. Analyses of ketamine were carried out by high performance liquid chromatography with diode array detection (HPLC-DAD). Other drugs of abuse were either detected via liquid chromatography with tandem mass spectromety (LC-MS/MS) and/or gas chromatography with (tandem) mass spectrometry (GC-MS(/MS)).

RESULTS

Ketamine plasma concentrations in a range of approx. 100-1200 ng/mL (mean: 510 ng/mL, median: 370 ng/mL) were detected. Co-consumption of at least one substance was ascertained in all cases. Besides driving impairments, recorded psychomotor impairments of the drivers comprised e.g. dilated pupils, missing or delayed pupil reactions, a slurred or decelerated speech, delayed reaction, lack of concentration, vertigo or agitation.

DISCUSSION

The observed peculiarities were in-line with literature data. However, the assessment and differentiation of ketamine-induced impairments was aggravated due to co-consumption of other drugs of abuse or pharmaceuticals in the herein investigated cases. Nevertheless, in two cases impairments can be attributed mainly to ketamine consumption since the co-consumed substances were only detected in low concentrations.

CONCLUSION

The presented cases provide additional data on psychomotor impairments observed in ketamine-related DUID cases. Limiting factors are co-consumption of substances, unknown habituation to drugs and the limited case number. Nevertheless, the results of this study are comparable with existing literature data. Since the abuse of ketamine has increased in the past years, these data will support forensic casework.

In vitro metabolism of cathinone positional isomers: does sex matter?

Synthetic cathinones, one of the most prevalent categories of new psychoactive substances, have been posing a serious threat to public health. Methylmethcathinones (MMCs), notably 3-MMC, have seen an alarming increase in their use in the last decade. The metabolism and toxicology of a large majority of synthetic cathinones, including 3-MMC and 2-MMC, remain unknown. Traditionally, male-derived liver materials have been used as in vitro metabolic incubations to investigate the metabolism of xenobiotics, including MMCs. Therefore, little is known about the metabolism in female-derived in vitro models and the potential sex-specific differences in biotransformation. In this study, the metabolism of 2-MMC, 3-MMC, and 4-MMC was investigated using female rat and human liver microsomal incubations, as well as male rat and human liver microsomal incubations. A total of 25 phase I metabolites of MMCs were detected and tentatively identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Seven sex-specific metabolites were detected exclusively using pooled male rat liver microsomal incubations. In addition, the metabolites generated from the sex-dependent in vitro metabolic incubations that were present in both male and female rat liver microsomal incubations showed differences in relative abundance. Yet, neither sex-specific metabolites nor significant differences in relative abundance were observed from pooled human liver microsomal incubations. This is the first study to report the phase I metabolic pathways of MMCs using in vitro metabolic incubations for both male and female liver microsomes, and the relative abundance of the metabolites observed from each sex.

Effects of 3,4-methylenedioxymethamphetamine and methamphetamine on motor vehicle driving performance: A systematic review of experimental and observational studies

Methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA) are common drugs of abuse and driving under their influence may occur in 1 million people yearly in the United States. This systematic review fills the currently unmet need in understanding the effects of METH and MDMA on motor vehicle driving performance (MVP) and provides insight into the forensic community. A PubMed search on September 24, 2020, for experimental and observational studies, which evaluated the impact of METH and MDMA on MVP was performed. After a review of 208 abstracts, 103 were considered potentially interesting and full texts were obtained. After the exclusion of non-English articles, review articles, single case reports, and articles which did not evaluate METH or MDMA on MVP, a total of nine experimental studies, 10 traditional observational studies, and 35 case series were included. The clinical rigor of experimental studies was evaluated using the Jadad scale. Experimental studies often demonstrated no significant MVP safety signals for METH or MDMA use, which was contrary to the overwhelming MVP safety risks found in observational studies. Common driving behaviors while using METH or MDMA include: errors in judgment, traveling at high speeds, failure to stop, merging inappropriately, lane weaving, and crashes. Limitations of experimental studies that led to dissimilar MVP outcomes from observational studies include: the common use of driving simulators, as opposed to actual driving examinations, and doses of METH or MDMA administered may not be representative of blood concentrations seen in observational studies. This systematic review has no funding source and was not registered.

Increasing Prevalence of Ketamine in Drivers in New York City Including the Identification of 2-Fluoro-Deschloroketamine

Ketamine is a dissociative anesthetic used in veterinary and human medicine since the 1970s. Its clinical use has expanded to control of seizures, pre-hospital emergency medical services (EMS), and is finding new purpose as an analgesic alternative and antidepressant. Ketamine brings hope for effective management of chronic pain in the absence of opioids, and decreasing suicidal ideations, however, its persistence as a recreational drug for its hallucinogenic properties remains. In the wake of expanding medicinal purposes, the diversity of New York City's population was explored to better understand its misuse. This retrospective study looks at the prevalence of ketamine in driver fatalities over a period of 18 years (2003-2020) and cases involving suspected driving under the influence of drugs (DUID) over a period of 6 years (2015-2020). Ketamine was identified in 6 driver fatalities and in 47 DUID cases. None of the driver fatalities were suspected of ketamine misuse, due to administration either in hospital or EMS administration. In the DUID cases, an increasing trend was observed over the 6-year study period with 100% (N = 47) of the cases confirmed as non-hospital/non-EMS administered ketamine. Of the DUID cases, 94% were male, with the majority between the age of 21-39 years (85%) and were predominantly Hispanic (36%) and Asian (34%). Blood concentrations of ketamine ranged from 27 to > 2000 ng/mL with polydrug use prevalent. The most common drug classes detected in addition to ketamine were cannabinoids (38%), ethanol (32%), benzodiazepines (26%), cocaine (19%), and amphetamines/MDMA (15%). In 2019, 2-fluoro-deschloroketamine (2F-DCK) was identified in two cases for the first time. Despite its increased acceptance for mental health disorders, ketamine's persistence and misuse as a recreational drug remains and should continue to be monitored by relevant toxicological, clinical, and law enforcement communities along with emerging illicit ketamine analogs.

Interference Free Method for Determination of Benzodiazepines in Urine Based on Restricted Access Supramolecular Solvents and LC-MS/MS

Supramolecular solvents with restricted access properties (SUPRAS-RAM) are proposed as a new approach for integrating extraction and sample cleanup in the quantification of benzodiazepines in urine by liquid chromatography tandem mass spectrometry (LC-MS/MS). The SUPRAS-RAM was synthesized in situ in the urine by the addition of 1- hexanol (154 µL) and THF (600 µL). Benzodiazepines extraction was driven by both hydrogen bonds and dispersion interactions. Removal of proteins and polar macromolecules was performed by the action of the SUPRAS through chemical and physical mechanisms. Phospholipids were removed by precipitation during SUPRAS extract evaporation. A multivariate method was used for the optimization of the extraction process by applying Box-Behnken response surface design. The proposed method was validated according to the guiding principles of the European Commission Decision (2002/657/EC). Method detection and quantification limits for the target benzodiazepines were in the intervals 0.21-0.85 ng/mL and 0.67-2.79 ng/mL, respectively. The repeatability and reproducibility (expressed as relative standard deviations) were in the range 2-6 % and 3-8%, respectively. The method enabled the simultaneous extraction of benzodiazepines (recoveries in the range 84-105%) and the removal of matrix effects. The method was applied to the analysis of 13 urine samples using external calibration. Five out of 13 samples tested positive in alprazolam and lorazepam at concentrations in the range 5.4-74 ng/mL. The method allows simple and quick sample treatment with minimal solvent consumption while delivering accurate and precise data.

Group-Targeting SERS Screening of Total Benzodiazepines Based on Large-Size (111) Faceted Silver Nanosheets Decorated with Zinc Oxide Nanoparticles

Rapid, quantitative, and group-targeting detection of total benzodiazepines (BZDs) is critical to create an accurate judgement in emergent medical and forensic settings. Large-size (111) faceted Ag nanosheets decorated with small ZnO nanoparticles were designed as the prominent surface-enhanced Raman scattering substrate, which possessed advantages of specific metal facets and additional charge-transfer (CT) effect from the semiconductor. The vital and bridge role of ZnO in the CT effect was systematically studied via experimental investigations and molecular dynamics simulation, which proves the essentiality of an appropriate ZnO decoration density. Upon determining optimal Ag NS/ZnO hybrids, a calibration curve of estazolam was established with a 0.5 nM detection limit. Based on the obtained curve, group-targeting screening was achieved toward total concentrations of five BZDs (estazolam, oxazepam, alprazolam, triazolam, and lorazepam). Importantly, the total concentrations of BZDs in mice serum were accurately monitored with changing analytical time during the metabolic process, which was in agreement with the tendency measured by liquid chromatography with tandem mass spectrometry.

Rate of elimination of γ-hydroxybutyrate from blood determined by analysis of two consecutive samples from apprehended drivers in Norway

AIM

Gamma-hydroxybutyrate (GHB) is a common drug of abuse with an elimination half-life of 20-45 min. However, there is some evidence that GHB might exhibit saturation kinetics after ingesting high recreational doses. The aim of this study was to investigate the elimination kinetics of GHB from blood in people apprehended by the police for impaired driving and secondary to describe concentrations in all GHB-positive drivers.

METHODS

Two consecutive blood samples were taken about 30-40 min apart from N = 16 apprehended drivers in Norway. GHB was determined in blood by an Ultra High-Performance Liquid Chromatography-Tandem Mass Spectrometry (UHPLC-MS/MS) method. The changes in GHB between the two consecutive blood samples allowed estimating GHB's elimination half-life, assuming first-order and zero-order elimination kinetics. GHB concentrations are also reported for N = 1276 apprehended drivers with GHB in blood.

RESULTS

The median time interval between collecting the two blood samples was 36 min (range 20-56 min). The median concentration of GHB in the first blood sample was 56.5 mg/L (range 14.1-142 mg/L) compared with 47.8 mg/L in the second sample (range 9.75-113 mg/L). The median elimination half-life was 103 min (range 21-187 min), and GHB's median zero-order elimination rate constant was 21.0 mg/L/h (range 6.71-45.4 mg/L/h). Back-calculation to the time of driving resulted in GHB concentrations up to 820 mg/L assuming first-order kinetics and up to 242 mg/L assuming zero-order kinetics. In all drivers (N = 1276), the median GHB concentration was 73.7 mg/L and highest was 484 mg/L.

CONCLUSION

The elimination half-life of GHB in blood samples from apprehended drivers was longer than expected compared with results of controlled dosing studies. Zero-order kinetics seems a more appropriate model for GHB when concentrations are back-calculated, and the median elimination rate was 21 mg/L/h.

The Emergence of Deschloro-N-ethyl-ketamine, a Ketamine Analog, in Drug Seizures and Drug Driving Cases in Hong Kong

The study reports the detection of a newly emerged drug, deschloro-N-ethyl-ketamine (2-oxo-PCE), an analog of ketamine, through forensic drug and toxicological examinations of exhibits from drug seizure cases and blood samples taken from drivers of driving under the influence of drug (DUID) cases, respectively, in Hong Kong. The submission of 2-oxo-PCE in both types of cases was firstly encountered in October 2017. A total of 31 drug seizure cases (52 items) and 4 DUID cases were found positive with 2-oxo-PCE till October 2018. Drug seizures with 2-oxo-PCE found were all in physical form (mostly in powdery or crystalline solid), resembling those samples commonly found with ketamine but having much lower purity. Although the majority of the relevant items was found with 2-oxo-PCE as the only psychoactive substance (36 items, ~69%) or as a mixture with ketamine (10 items, ~19%), other psychoactive substances including methamphetamine, methylenedioxymethamphetamine and pentylone have also been encountered (6 items, 12%). For the four DUID cases, 2-oxo-PCE and its metabolite, deschloronorketamine, were detected in all blood samples. The 2-oxo-PCE concentrations in the four blood samples were in the range of 0.08–0.31 μg/mL, being higher than the concentrations of deschloronorketamine (in the range of 0.04–0.09 μg/mL) for each sample. The 2-oxo-PCE levels found were generally lower than the ketamine levels found in reported DUID cases. With items found with 2-oxo-PCE, which were physically indistinguishable from ketamine but having lower drug purity in seizures, the lower 2-oxo-PCE blood levels with more severe impairment signs observed for the drivers in DUID cases, it is not unreasonable to speculate that users might have taken it as ketamine without knowing of its real identity and hence was adversely affected by the more potent 2-oxo-PCE.

Endogenous Gamma-Hydroxybutyrate in Postmortem Samples

Gamma-hydroxybutyrate (GHB) is a naturally occurring molecule present in the human body as a catabolite of the neurotransmitter gamma-aminobutyrate (GABA). In the USA, GHB has a history of being manufactured illicitly and abused, with misguided proposed benefits for the body-building community and a persistent party drug with reported GHB overdoses occurring worldwide. The interpretation of GHB in postmortem biological fluids is complicated by the endogenous nature of the molecule. Analysis often requires more than one biological matrix to detect exogenous exposure, typically in urine. The analysis is further complicated by the endogenous de novo production of GHB in postmortem specimens. This work sought to examine the prevalence of endogenous GHB concentrations in postmortem toxicology samples from Orange County, CA, and to establish suitable in-house secondary matrices to confirm or rule out exogenous GHB exposure. A total of 348 postmortem heart blood samples were randomly selected and analyzed for GHB using liquid–liquid extraction followed by gas chromatography–mass spectrometry with selective ion monitoring and GHB-d6 as an internal standard. Of the 348 cases analyzed, 39 cases resulted in positive GHB detection with the median concentration of 22.45 mg/L (10.4–62.16 mg/L). None of the positive samples had suspected GHB ingestion or usage from the case report. GHB concentrations were then examined in secondary matrices collected at autopsy from the positive cases that included (when available) peripheral blood, urine, vitreous humor, liver homogenate and brain homogenate. Within the secondary matrices, GHB levels in peripheral blood compared to that of heart blood, while liver homogenate levels were variable. Quantifiable GHB levels were not identified in vitreous humor and brain homogenate samples. Our findings reaffirm the importance of multi-matrix analysis in postmortem toxicology and further confirm the utility of vitreous humor and brain tissue to distinguish exogenous GHB exposure from endogenous production.

Effect of γ-hydroxybutyrate (GHB) on driving as measured by a driving simulator

RATIONALE

Gamma-hydroxybutyrate acid (GHB), a GABA_B receptor agonist approved for treatment of narcolepsy, impairs driving ability, but little is known about doses and plasma concentrations associated with impairment and time course of recovery.

OBJECTIVE

To assess effects of oral GHB (Xyrem®) upon driving as measured by a driving simulator, and to determine plasma concentrations associated with impairment and the time course of recovery.

METHODS

Randomized, double-blind, two-arm crossover study, during which 16 participants received GHB 50 mg/kg orally or placebo. GHB blood samples were collected prior to and at 1, 3, and 6 h post dosing. Driving simulator sessions occurred immediately after blood sampling.

RESULTS

Plasma GHB was not detectable at baseline or 6 h post dosing. Median GHB concentrations at 1 and 3 h were 83.1 mg/L (range 54-110) and 24.4 mg/L (range 7.2-49.7), respectively. Compared to placebo, at 1 h post GHB dosing, significant differences were seen for the life-threatening outcome collisions (p < 0.001) and off-road accidents (p = 0.018). Although driving was not faster, there was significantly more weaving and erratic driving with GHB as measured by speed deviation (p = 0.002) and lane position deviation (p = 0.004). No significant impairment regarding driving outcomes was found in the GHB group at 3 and 6 h post dose.

CONCLUSION

GHB in doses used to treat narcolepsy resulted in severe driving impairment at 1 h post dosing. After 3 to 6 h, there was full recovery indicating that safe driving is expected the next morning after bedtime therapeutic GHB use in the absence of other substances.

[The influence of the packaging on the storage qualities of the volatile substances]

The objective of the present study was to evaluate the storage qualities of the acetone and ethanol aqueous solutions kept in the polyethylene flasks, polypropylene and glass tubes that were stored under different environmental temperature. It was shown that the acetone aqueous solution better retained its properties when stored in glass vials at room temperature as well as at 0° C and 4° C. The most pronounced decrease of acetone concentrations (from 70 up to 95%) was documented after its storage in the polyethylene flasks. The ethanol concentration fell down by 40% when stored in polyethylene flasks at room temperature.

The acute and residual effects of escalating, analgesic-range doses of ketamine on driving performance: A simulator study

Ketamine hydrochloride elicits potent psychotomimetic and neurobehavioural effects which make it incompatible with driving; however, the direct effect on driving performance is yet to be assessed. Using an open label, within-subjects protocol, 15 males and 5 females (mean age = 30.8 years) were administered three fixed, stepwise increasing sub-anaesthetic doses of intravenous (IV) ketamine solution [(i) 8 mg/h IV infusion plus 30 mg bolus, (ii) 12 mg/h IV infusion and (iii) 20 mg/h infusion]. Whole blood ketamine and norketamine concentrations were determined at each treatment step and at 2 h post-infusion. Driving performance was assessed at baseline, at each treatment step and at 2 h post-treatment using a validated computerised driving simulator. Standard Deviation of Lateral Position (SDLP) and Steering Variability (SV) were assessed. Linear Fixed Effect Modelling indicated a main effect for time (dose) for SDLP (F_[4,72] = 33.22, p < 0.0001) and SV (F_[4,72] = 4.65, p < 0.002). Post-hoc analyses revealed significant differences from baseline at each treatment step for SDLP (all p < 0.001), and for 12 mg/h treatment step for SV (p = 0.049). Post-treatment driving performance returned to baseline levels. Weak positive linear associations were observed between SDLP and whole blood ketamine concentrations (R² = 0.11, β = 29.96, p = 0.001) and norketamine (R² = 0.09, β = 28.87, p = 0.003). These findings suggest that even under highly controlled conditions, ketamine intoxication significantly alters simulated driving performance. At the highest dose, ketamine produced changes to SDLP considered incompatible with safe driving, highlighting how ketamine consumption may translate to an increased risk of road trauma.

Ethanol addictively enhances the in vitro cardiotoxicity of cocaine through oxidative damage, energetic deregulation, and apoptosis

Cocaine (COC) is frequently consumed in polydrug abuse settings, and ethanol (EtOH) is the most prominent co-abused substance. Clinical data and experimental evidence suggest that the co-administration of COC with EtOH can be more cardiotoxic than EtOH or COC alone, but information on the molecular pathways involved is scarce. Since these data are crucial to potentiate the identification of therapeutic targets to treat intoxications, we sought to (i) elucidate the type of interaction that occurs between both substances, and (ii) assess the mechanisms implicated in the cardiotoxic effects elicited by COC combined with EtOH. For this purpose, H9c2 cardiomyocytes were exposed to COC (104 µM-6.5 mM) and EtOH (977 µM-4 M), individually or combined at a molar ratio based on blood concentrations of intoxicated abusers (COC 1: EtOH 9; 206 µM-110 mM). After 24 h, cell metabolic viability was recorded by the MTT assay and mixture toxicity expectations were calculated using the independent action (IA) and concentration addition (CA) models. EtOH (EC₅₀ 305.26 mM) proved to act additively with COC (EC₅₀ 2.60 mM) to significantly increase the drug in vitro cardiotoxicity, even when both substances were combined at individually non-cytotoxic concentrations. Experimental mixture testing (EC₅₀ 19.18 ± 3.36 mM) demonstrated that the cardiotoxicity was fairly similar to that predicted by IA (EC₅₀ 22.95 mM) and CA (EC₅₀ 21.75 mM), supporting additivity. Concentration-dependent increases of intracellular ROS/RNS and GSSG, depletion of GSH and ATP, along with mitochondrial hyperpolarization and activation of intrinsic, extrinsic, and common apoptosis pathways were observed both for single and combined exposures. In general, the mixture exhibited a toxicological profile that mechanistically did not deviate from the single drugs, suggesting that interventions such as antioxidant administration might aid in the clinical treatment of this type of polydrug intoxication. In a clinical perspective, the observed additive mixture effect may reflect the increased hazards at which users of this combination are exposed to in recreational settings.

Underestimation of sudden deaths among patients with seizures and epilepsy

OBJECTIVE

To determine the definite and potential frequency of seizures and epilepsy as a cause of death (COD) and how often this goes unrecognized.

METHODS

Prospective determination of seizures or epilepsy and final COD for individuals aged 18-90 years with out-of-hospital sudden cardiac deaths (SCDs) from the population-based San Francisco POST SCD Study. We compared prospective seizure or epilepsy diagnosis and final COD as adjudicated by a multidisciplinary committee (pathologists, electrophysiologists, and a vascular neurologist) vs retrospective adjudication by 2 epileptologists with expertise in seizure-related mortality.

RESULTS

Of 541 SCDs identified during the 37-month study period (mean age 62.8 years, 69% men), 525 (97%) were autopsied; 39/525 (7.4%) had seizures or epilepsy (mean age: 58 years, range: 27-92; 67% men), comprising 17% of 231 nonarrhythmic sudden deaths. The multidisciplinary team identified 15 cases of epilepsy, 6 sudden unexpected deaths in epilepsy (SUDEPs), and no deaths related to acute symptomatic seizures. The epileptologists identified 25 cases of epilepsy and 8 definite SUDEPs, 10 possible SUDEPs, and 5 potential cases of acute symptomatic seizures as a COD.

CONCLUSIONS

Among the 25 patients identified with epilepsy by the epileptologists, they found definite or possible SUDEP in 72% (18/25) vs 24% (6/25) by the multidisciplinary group (6/15 cases they identified with epilepsy). The epileptologists identified acute symptomatic seizures as a potential COD in 5/14 patients with alcohol-related seizures. Epilepsy is underdiagnosed among decedents. Among patients with seizures and epilepsy who die suddenly, seizures and SUDEP often go unrecognized as a potential or definite COD.

The Novel Psychoactive Substances in the UK Project: empirical and conceptual review work to produce research recommendations

Background

Although illegal drug use has largely been declining in the UK over the past decade, this period has witnessed the emergence of a range of novel psychoactive substances (NPS) (‘legal highs’). These are new, mostly synthetic, substances that mimic the effects of existing drugs). Despite there being many causes for concern in relation to NPS, there has been little prior study of the burden associated with their use in public health terms. Clarity is lacking on research priorities in this rapidly developing literature.

Objectives

To inform the development of public health intervention research on NPS by reviewing existing data on their use, associated problems and potential responses to such problems.

Design

A scoping review and narrative synthesis of selected bodies of evidence was undertaken to summarise and evaluate what is known about NPS use and the related harms of, and responses to, such use. Relevant literature was identified from electronic databases (covering January 2006 to June 2016 inclusive), Google (Google Inc., Mountain View, CA, USA), relevant websites and online drug forums and by contacting experts. Articles were included if they were primary studies, secondary studies involving the analysis and interpretation of primary research or discussion papers. A conceptual framework postulating an evidence-informed public health approach to NPS use in the UK was developed through a pragmatic literature review, the iterative development of concepts and finalisation in light of the results from the empirical review work. The process also involved feedback from various stakeholders. Research recommendations were developed from both strands of work.

Results

A total of 995 articles were included in the scoping review, the majority of which related to individual-level health-related adverse effects attributable to NPS use. The prevalence of lifetime NPS use varied widely between (e.g. with higher prevalence in young males) and within population subgroups. The most commonly reported adverse effects were psychiatric/other neurological, cardiovascular, renal and gastrointestinal manifestations, and there is limited evidence available on responses. In these and other respects, available evidence is at an early stage of development. Initial evidence challenges the view that NPS should be treated differently from other illicit drugs. The conceptual framework indicated that much of the evidence that would be useful to inform public health responses does not yet exist. We propose a systems-based prevention approach that develops existing responses, is multilevel and life course informed in character, and emphasises commonalities between NPS and other legal and illegal drug use. We make 20 recommendations for research, including nine key recommendations.

Limitations

Scoping reviews do not interrogate evidence in depth, and the disjunction between the scoping review and the conceptual framework findings is worthy of careful attention.

Conclusions

Key research recommendations build on those that have previously been made and offer more evidence-based justification and detail, as previous recommendations have not yet been acted on. The case for decision-making on commissioning new research based on these recommendations is both strong and urgent.

Future work

The validity of recommendations generated through this project could be enhanced via further work with research commissioners, policy-makers, researchers and the public.

Study registration

The systematic review element of this study is registered as PROSPERO CRD42016026415.

Funding

The National Institute for Health Research Public Health Research programme.

Drugged Drivers Blood Concentrations in England and Wales Prior to the Introduction of Per Se Limits

This report details the blood concentration of drugs found in motorists suspected of driving under the influence of drugs from 2010 to 2012 in England and Wales. This study was carried out as new legislation has come into place, setting fixed blood concentration limits for drugs in motorists. These include a cannabis (Δ9-THC) blood concentration of 2 µg/L, amphetamine 250 µg/L, benzoylecgonine (BZE) 50 µg/L, cocaine 10 µg/L, 6-monoacetylmorphine 5 µg/L, morphine 80 µg/L, diazepam 550 µg/L and methadone 500 µg/L. Samples were screened for opiates, methadone, benzodiazepines, cannabinoids, cocaine, amphetamines and methamphetamine. Cannabinoids were the most prevalent drug group (29.7%) followed by benzodiazepines (22.7%), opiates (18.8%), cocaine (16.3%), amphetamine (7%) and methadone (5.6%). The analytical results are compared with the new per se limits to give a reference of drug concentrations prior to this legislation coming into effect. Our studies show that 64.9% of the cannabis samples, 59.1% of the cocaine samples and 94.6% of the BZE samples would be above the new per se limits set under Section 5a of the Road Traffic Act. In contrast, the medicinal drugs such as benzodiazepines and opiates (morphine) were predominantly detected at concentrations below the new per se limit. Given its medical applications, amphetamines appear to have been grouped with the medicinal type drugs, with our data showing that 25.2% of the amphetamine positive samples would exceed the new specified limit. These data show that samples containing medicinal and prescription drugs are likely to be detected below the new legal limits, while illicit drugs were typically found at concentrations above the new specified limits.

Clinical Pharmacology of the Synthetic Cathinone Mephedrone

4-Methyl-N-methylcathinone (mephedrone) is a popular new psychoactive substance (NPS) that is structurally related to the parent compound cathinone, the β-keto analogue of amphetamine. Mephedrone appeared on the street drug market as a substitute for 3,4-methylenedioxy-N-methylamphetamine (MDMA, ecstasy) and was subsequently banned due to the potential health risks associated with its use. Nevertheless, mephedrone continues to be widely consumed among specific populations, with unique patterns of misuse. To date, most information about the biological effects of mephedrone comes from user experiences, epidemiological data, clinical cases, toxicological findings, and animal studies, whilst there are very few data regarding its human pharmacodynamics and pharmacokinetics. This chapter reviews the available published data on patterns of mephedrone use, its acute and chronic effects, and its pharmacokinetic properties. More human research is needed to elucidate the safety, toxicity, and addiction potential of mephedrone and related NPS.

Non-prescribed use of psychoactive prescription drugs among drug-impaired drivers in Sweden

AIMS

To determine the prevalence of non-prescribed drug use among subjects suspected of drug-impaired driving with a psychoactive prescription drug, and to identify associated factors.

METHODS

Subjects investigated for drug-impaired driving in Sweden during 2006-2009 with a confirmed intake of diazepam, flunitrazepam, tramadol, zolpidem or zopiclone were identified using the Swedish Forensic Toxicology Database. Information on dispensed prescription drugs was retrieved from the Swedish Prescribed Drug Register. Non-prescribed use was our outcome, defined as a psychoactive prescription drug intake confirmed by toxicological analysis in a subject by whom it was not dispensed in the 12 months preceding the sampling. Prevalence proportions were calculated for each drug and logistic regression was used to identify associated factors.

RESULTS

In total, 2225 subjects were included. The median age (range) was 34 (15-80) years and 1864 (83.8%) subjects were male. Non-prescribed use was found in 1513 subjects (58.7%); for flunitrazepam 103 (76.3%), diazepam 1098 (74.1%), tramadol 192 (40.3%), zopiclone 60 (29.7%), and zolpidem 60 (21.2%) subjects, respectively. Younger age and multiple-substance use were associated with non-prescribed use, whereas ongoing treatment with other psychoactive drugs was negatively associated with non-prescribed use.

CONCLUSIONS

Non-prescribed use of psychoactive prescription drugs was common in subjects suspected of drug-impaired driving and was more frequent for benzodiazepines and tramadol compared to zolpidem and zopiclone. The young and multi-substance users were more likely, whereas subjects with ongoing prescribed treatment with other psychoactive drugs were less likely, to use non-prescribed drugs.

Metabolic profile of mephedrone: Identification of nor-mephedrone conjugates with dicarboxylic acids as a new type of xenobiotic phase II metabolites

Metabolic profile of mephedrone (4-methylmethcathinone, 4-MMC), a frequently abused recreational drug, was determined in rats in vivo. The urine of rats dosed with a subcutaneous bolus dose of 20mg 4-MMC/kg was analysed by LC/MS. Ten phase I and five phase II metabolites were identified by comparison of their retention times and MS(2) spectra with those of authentic reference standards and/or with the MS(2) spectra of previously identified metabolites. The main metabolic pathway was N-demethylation leading to normephedrone (4-methylcathinone, 4-MC) which was further conjugated with succinic, glutaric and adipic acid. Other phase I metabolic pathways included oxidation of the 4-methyl group, carbonyl reduction leading to dihydro-metabolites and ω-oxidation at the position 3'. Five of the metabolites detected, namely, 4-carboxynormephedrone (4-carboxycathinone, 4-CC), 4-carboxydihydronormephedrone (4-carboxynorephedrine, 4-CNE), hydroxytolyldihydro-normephedrone (4-hydroxymethylnorephedrine, 4-OH-MNE) and conjugates of 4-MC with glutaric and adipic acid, have not been reported as yet. The last two conjugates represent a novel, hitherto unexploited, type of phase II metabolites in mammals together with an analogous succinic acid conjugate of 4-MC identified by Pozo et al. (2015). These conjugates might be potentially of great importance in the metabolism of other psychoactive amines.

Analysis of phenazepam and 3-hydroxyphenazepam in post-mortem fluids and tissues

Phenazepam is a benzodiazepine that is predominantly used clinically in the former Soviet states but is being abused throughout the wider world. This study reports the tissue distribution and concentration of both phenazepam and 3-hydroxyphenazepam in 29 cases quantitated by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in a variety of post-mortem fluids (subclavian blood, femoral blood, cardiac blood, urine, vitreous humour) and tissues (thalamus, liver and psoas muscle). In 27 cases, the cause of death was not directly related to phenazepam (preserved (fluoride/oxalate) femoral blood phenazepam concentrations 0.007 mg/L to 0.360 mg/L (median 0.097 mg/L). In two cases, phenazepam was either a contributing factor to, or the certified cause of death (preserved (fluoride/oxalate) femoral blood 0.97 mg/L and 1.64 mg/L). The analysis of phenazepam and 3-hydroxyphenazepam in this study suggests that they are unlikely to be subject to large post-mortem redistribution and that there is no direct correlation between tissues/fluid and femoral blood concentrations. Preliminary investigations of phenazepam stability comparing femoral blood phenazepam concentrations in paired preserved (2.5% fluoride/oxalate) and unpreserved blood show that unpreserved samples show on average a 14% lower concentration of phenazepam and we recommend that phenazepam quantitation is carried out using preserved samples wherever possible.

The culpability of drivers killed in New Zealand road crashes and their use of alcohol and other drugs

Over a period of five years, blood samples were taken from 1046 drivers killed as a result of a motor vehicle crash on New Zealand roads. These were analysed for the presence of alcohol and a range of both illicit drugs and psychoactive medicinal drugs. Driver culpability was determined for all crashes. The control group of drug- and alcohol-free drivers comprised 52.2% of the study population. Drivers positive for psychoactive drugs were more likely to be culpable (odds ratio (OR) 3.5, confidence interval (CI) 95% 2.4-5.2) than the control group. Driver culpability exhibited the expected positive association with alcohol use (OR 13.7, 95% CI 4.3-44) and with combined alcohol and cannabis use (OR 6.9, 95% CI 3.0-16). There was only a weak positive association between cannabis use (with no other drug) and culpability (OR 1.3, CI 95% 0.8-2.3). Furthermore, the OR for drivers with blood tetrahydrocannabinol (THC) concentrations greater than 5 ng/mL was lower (OR 1.0, CI 95% 0.4-2.4) than drivers with blood THC concentrations less than 2 ng/mL (OR 3.1, CI 95% 0.9-10). This is inconsistent with results reported by other studies where a significant increase in crash risk was found with blood THC levels greater than 5 ng/mL. In this study, there were very few drivers who had used a single drug, other than cannabis or alcohol. Therefore, from this study, it is not possible to comment on any relationship between opioid, stimulant or sedative drug use and an increased risk of being killed in a crash for the drivers using these drugs. The results from a multivariate analysis indicate that driver gender, age group and licence status, (P=0.022, P=0.016, P=0.026, respectively), the type of vehicle being driven (P=0.013), the number of vehicles in the crash (P<0.001), the blood alcohol concentration of the driver (P<0.001) and the use of any drug other than alcohol and cannabis (P=0.044), are all independently associated with culpability.

Concentrations of cocaine and benzoylecgonine in femoral blood from cocaine-related deaths compared with venous blood from impaired drivers

The concentrations of cocaine and its major metabolite benzoylecgonine (BZE) were determined in femoral blood from 132 cocaine-related deaths and compared with venous blood from 988 apprehended drivers. Cocaine and BZE were determined by solid-phase extraction and isotope dilution gas chromatography-mass spectrometry with limits of quantitation of 0.02 mg/L for both substances. Significantly more men (95-98%) than women (2-5%) abused cocaine, although their mean age was about the same (29-30 years). Mean age (±SD) of cocaine-related deaths was 29 ± 7 years, which was not significantly different from 30 ± 8 years in traffic cases (P > 0.05). The median concentration of cocaine in blood in 61 fatalities was 0.10 mg/L compared with 0.06 mg/L in traffic cases (P < 0.001). In drug intoxication deaths, the median concentration of cocaine was 0.13 mg/L (N = 25), which was not significantly different from 0.09 mg/L (N = 36) in other causes of death. Cocaine-related deaths mostly involved mixed drug intoxications including co-ingestion of heroin, cannabis, amphetamines as well as legal drugs, such as benzodiazepines and/or ethanol. The concentrations of cocaine in blood from living and deceased persons overlapped, which makes it infeasible to predict toxicity from the analytical toxicology results alone.

Lack of impairment due to confirmed codeine use prior to a motor vehicle accident: role of pharmacogenomics

BACKGROUND

We examined forensic serum toxicology and pharmacogenomics data from a woman on codeine shortly before she caused a motor vehicle accident.

METHODS

A woman driving erratically collided with a parked car of a highway seriously injuring 2 men working to repair the parked vehicle. The woman tested positive for codeine, acetaminophen and barbital. She had been taking these medications for 20 years due to migraine headache. Serum toxicology and genotype analysis for cytochrome P450, UDP glucuronosyltransferase, and other metabolizing enzymes were measured.

RESULTS

The woman was tried and convicted of driving under the influence resulting in bodily harm and was sentenced to 6 years. Toxicology results on peripheral blood showed a total and free codeine of 840 and 348 μg/L, respectively, and total morphine of 20 μg/L (17, 3, and 0 μg/L for morphine-3-glucuronide, morphine-6-glucuronide, and free morphine, respectively). She was heterozygous for CYP 2D6 *2/*4 (extensive/poor metabolism) and heterozygous for UGT 2B7 *1/*2 (extensive/ultra-rapid metabolism). The woman was also taking fluoxetine and bupropion which are strong inhibitors of CYP 2D6.

CONCLUSIONS

Based on her genotype and phenotype and reports by the arresting officer, we suggest that the subject in question was not intoxicated by opiates at the time of her motor vehicle accident and may have been falsely incarcerated.