Synthetic cannabinoids: the multi-organ failure and metabolic derangements associated with getting high

Log D7.4 and plasma protein binding of synthetic cannabinoid receptor agonists and a comparison of experimental and predicted lipophilicity

The emergence of new synthetic cannabinoid receptor agonists (SCRAs) onto the illicit drugs market continues to cause harm, and the overall availability of physicochemical and pharmacokinetic data for new psychoactive substances is lacking. The lipophilicity of 23 SCRAs and the plasma protein binding (PPB) of 11 SCRAs was determined. Lipophilicity was determined using a validated chromatographic hydrophobicity index (CHI) log D method; tested SCRAs showed moderate to high lipophilicity, with experimental log D7.4 ranging from 2.48 (AB-FUBINACA) to 4.95 (4F-ABUTINACA). These results were also compared to in silico predictions generated using seven commercially available software packages and online tools (Canvas; ChemDraw; Gastroplus; MoKa; PreADMET; SwissADME; and XlogP). Licenced, dedicated software packages provided more accurate lipophilicity predictions than those which were free or had prediction as a secondary function; however, the latter still provided competitive estimates in most cases. PPB of tested SCRAs, as determined by equilibrium dialysis, was in the upper range of the lipophilicity scale, ranging from 90.8% (ADB-BUTINACA) to 99.9% (BZO-HEXOXIZID). The high PPB of these drugs may contribute to reduced rate of clearance and extended durations of pharmacological effects compared to lesser-bound SCRAs. The presented data improve understanding of the behaviour of these drugs in the body. Ultimately, similar data and predictions may be used in the prediction of the structure and properties of drugs yet to emerge on the illicit market.

Renal manifestations of recreational drugs: A narrative review of the literature

Drug abuse has become a major problem of the modern world where drug-induced kidney injury can be caused by both prescribed drugs for clinical conditions and illegal (illicit) drugs or drugs of abuse. Heroin, cocaine, nicotine and alcohol are the most commonly abused drugs but with the emergence of various synthetic drugs, numerous novel descriptions of their nephrotoxic effects have been described. This review summarizes the key renal manifestations of recreational drugs as reported in case reports and case. A comprehensive review of published case reports and case series in English language of renal toxicity related to recreational drugs/drugs of abuse was conducted using search engines like PubMed/Medline. Publications which reported renal injury with raised creatinine levels, clinically symptomatic patients, those with oliguria and with renal biopsies are chosen. The medical literature on recreational drugs is full of claims of renal complications including different glomerular diseases, acute kidney injury, rhabdomyolysis, interstitial nephritis, and debilitating irreversible conditions like renal infarction and end stage renal disease, even though the pathogenesis of drug- related renal manifestations are not available for all the newer agents. The outcome of this review paper will help multidisciplinary physicians to understand the renal side effects of recreational drugs, their pathophysiology, and most importantly, the clinical presentations of renal dysfunction in relation each drug. Emphasizing these adverse effects will prevent future unfavorable outcomes.

Acute Hepatic Injury Associated with Acute Administration of Synthetic Cannabinoid XLR-11 in Mouse Animal Model

The widespread recreational use of synthetic cannabinoids (SCs) has become a serious health issue. Reports of life-threatening intoxications related to SC consumption have markedly increased in recent years, including neurotoxicity, cardiotoxicity, nephrotoxicity, and hepatotoxicity. We investigated the impact of acute administration of the synthetic cannabinoid XLR-11 (3 mg/kg, i.p. for 5 consecutive days) on the liver in BALB/c mouse animal model. Using real-time quantitative RT-PCR, MDA assay, and TUNEL assay, we found consistent up-regulation of a variety of genes involved in oxidative stress (NOX2, NOX4, and iNOS), inflammation (TNF-α, IL-1β, IL-6), and apoptosis (Bax) in the liver of XLR-11 treated mice compared to control mice. These finding were supported with an elevation of MDA levels and TUNEL positive cells in the liver of XLR-11 treated mice which further confirm increased oxidative stress and apoptosis, respectively. Histopathological analysis of the liver of XLR-11 treated mice confirmed pronounced hepatic necrosis associated with inflammatory cell infiltration. Furthermore, elevated ALT and AST serum levels were also identified in XLR-11 treated mice indicating possible liver damage. Overall, SC-induced hepatotoxicity seems to be mainly mediated by activated oxidative stress and inflammatory processes in the liver, but the specific mechanisms involved require further investigations. However, the present study shed light on the potential deleterious role of acute administration of SCs in the progression to acute hepatic injury which enhances our understanding of the adverse effect of SC consumption.

Synthetic cannabinoids and ST elevation myocardial infarction

Synthetic cannabinoids cannot be detected on a standard urine drug screen (UDS), making them a convenient drug of abuse. We report the first case of ST elevation myocardial infarction (STEMI) in a young patient due to coronary artery thrombosis secondary to synthetic cannabinoid use and concurrent COVID-19 infection. A 38-year-old previously healthy male developed severe chest pain and was found to have anterior STEMI and COVID-19 infection. Coronary angiography showed acute thrombotic occlusion of the mid-left anterior descending artery that was managed with thrombectomy and stent placement. He only required supportive care for COVID-19. A comprehensive literature search revealed 34 additional cases of STEMI with synthetic cannabinoid use; majority were males (97%) with mean age of 29 years. 29 patients (85.3%) underwent coronary angiography and majority had left anterior descending artery (LAD) involvement (55%), with 13 (44.8%) undergoing stent placement. We highlight STEMI as a potentially lethal complication of synthetic cannabinoids; prompt angiography may be lifesaving.

Acute Kidney Injury (AKI) in Young Synthetic Cannabinoids Abusers

Background. Synthetic cannabinoid-related acute kidney injury represents an increasingly important public health issue due to the diagnostic challenges given by low clinical suspicion of the disease and the frequent undetectability in routine drug tests. Methods. A systematic literature search on PubMed was carried out until 31 January 2022. Case reports, case series, retrospective and prospective studies, as well as reviews on acute kidney injury related to the consumption of synthetic cannabinoid were searched. Results. The systematic review process selected 21 studies for a total of 55 subjects with synthetic cannabinoid-induced acute kidney injury. Renal damage was demonstrated by elevated serum creatinine levels in 49 patients (89%). On renal ultrasound, the most frequent finding was an increase in cortical echogenicity. Renal biopsy, performed in 33% of cases, revealed acute tubular damage, acute tubulointerstitial nephritis, and acute interstitial nephritis, in decreasing order of frequency. Conclusion. Prompt identification and treatment of synthetic cannabinoid-related acute kidney injury represent a sensitive public health goal both for the acute management of damage from synthetic cannabinoids and for the prevention of chronic kidney disease.

Quantitation of Synthetic Cannabinoid Receptor Agonists in Postmortem Blood Using a Single Point Calibration

Synthetic cannabinoid receptor agonists (SCRA) share minimal structural similarities to tetrahydrocannabinol or themselves. Due to their heterogeneous structures and the rapid appearance and disappearance of new SCRA on the drug scene, the quantitation of SCRA has not been attempted extensively. We present a wide series of SCRA concentrations based on a single-point calibration using peak height ratios for the extracted ion chromatogram of the protonated precursor ion against that of the internal standard. These concentrations are viewed as indicative only given the use of a single concentration "calibrator" based on the response of a deuterated analogue of a structurally related compound. What is of note, is that, despite the potential differences in potency the majority of SCRA seem to have relatively similar concentrations in postmortem cases.

Cytotoxicity, metabolism, and isozyme mapping of the synthetic cannabinoids JWH-200, A-796260, and 5F-EMB-PINACA studied by means of in vitro systems

Intake of synthetic cannabinoids (SC), one of the largest classes of new psychoactive substances, was reported to be associated with acute liver damage but information about their hepatotoxic potential is limited. The current study aimed to analyze the hepatotoxicity including the metabolism-related impact of JWH-200, A-796260, and 5F-EMB-PINACA in HepG2 cells allowing a tentative assessment of different SC subclasses. A formerly adopted high-content screening assay (HCSA) was optimized using a fully automated epifluorescence microscope. Metabolism-mediated effects in the HCSA were additionally investigated using the broad CYP inhibitor 1-aminobenzotriazole. Furthermore, phase I metabolites and isozymes involved were identified by in vitro assays and liquid chromatography–high-resolution tandem mass spectrometry. A strong cytotoxic potential was observed for the naphthoylindole SC JWH-200 and the tetramethylcyclopropanoylindole compound A-796260, whereas the indazole carboxamide SC 5F-EMB-PINACA showed moderate effects. Numerous metabolites, which can serve as analytical targets in urine screening procedures, were identified in pooled human liver microsomes. Most abundant metabolites of JWH-200 were formed by N-dealkylation, oxidative morpholine cleavage, and oxidative morpholine opening. In case of A-796260, most abundant metabolites included an oxidative morpholine cleavage, oxidative morpholine opening, hydroxylation, and dihydroxylation followed by dehydrogenation. Most abundant 5F-EMB-PINACA metabolites were generated by ester hydrolysis plus additional steps such as oxidative defluorination and hydroxylation. To conclude, the data showed that a hepatotoxicity of the investigated SC cannot be excluded, that metabolism seems to play a minor role in the observed effects, and that the extensive phase I metabolism is mediated by several isozymes making interaction unlikely.

Severe Vitamin K-dependent Coagulopathy from Rodenticide-contaminated Synthetic Cannabinoids: Emergency Department Presentations

INTRODUCTION

Synthetic cannabinoids are a rapidly expanding subset of designer drugs widely available in the United States since 2008. In Illinois during the spring of 2018, over 160 documented cases of bleeding and prolonged coagulopathy occurred secondary to contaminated synthetic cannabinoids.

METHODS

We conducted a retrospective cohort study consisting of 38 patients to describe the initial emergency department (ED) presentation, diagnosis, and treatment.

RESULTS

Through serum testing we found that three long-acting anticoagulant rodenticides (LAAR) were detected in patients who had inhaled these tainted products: brodifacoum, difenacoum, and bromodialone.

DISCUSSION

This study encompasses the largest ED presentation of LAAR poisoning via the inhalational route known to date.

CONCLUSION

The emergency physician should be aware of the potential for tainted coingestants as the cause of undifferentiated coagulopathy.

Marijuana: A systems-based primer of adverse effects associated with use and an overview of its therapeutic utility

Marijuana use is on the rise in the United States. By the end of 2019, 33 states have legalized marijuana use and marijuana byproduct use for medical purposes. However, marijuana use does not come without side effects. This manuscript reviews the increasing usage of marijuana and the different forms (natural and synthetic) that patients may use when presenting to clinicians. It also addresses the biochemical and behavioral changes observed with marijuana use, including the location and changes associated with cannabinoid receptors (abbreviated CB1 and CB2). These two topics lead into an extensive review of the side effects of marijuana use. This manuscript discusses gastrointestinal side-effects, such as Cannabinoid Hyperemesis Syndrome, pancreatitis, and hepatotoxicity. It also briefly reviews cardiovascular, neurologic, and pulmonary side effects. This article provides an overview of therapeutic effects of marijuana including the antiemetic effect, its medical utility as an appetite stimulant, and usefulness in cancer patients post-chemotherapy. A thorough social history pertaining to marijuana use is an important consideration for clinicians in patients presenting with a variety of symptoms, including those effecting the gastrointestinal, cardiovascular, pulmonary, or neurologic systems.

A Systematic Study of the In Vitro Pharmacokinetics and Estimated Human In Vivo Clearance of Indole and Indazole-3-Carboxamide Synthetic Cannabinoid Receptor Agonists Detected on the Illicit Drug Market

In vitro pharmacokinetic studies were conducted on enantiomer pairs of twelve valinate or tert-leucinate indole and indazole-3-carboxamide synthetic cannabinoid receptor agonists (SCRAs) detected on the illicit drug market to investigate their physicochemical parameters and structure-metabolism relationships (SMRs). Experimentally derived Log D_7.4 ranged from 2.81 (AB-FUBINACA) to 4.95 (MDMB-4en-PINACA) and all SCRAs tested were highly protein bound, ranging from 88.9 ± 0.49% ((R)-4F-MDMB-BINACA) to 99.5 ± 0.08% ((S)-MDMB-FUBINACA). Most tested SCRAs were cleared rapidly in vitro in pooled human liver microsomes (pHLM) and pooled cryopreserved human hepatocytes (pHHeps). Intrinsic clearance (CL_int) ranged from 13.7 ± 4.06 ((R)-AB-FUBINACA) to 2944 ± 95.9 mL min⁻¹ kg⁻¹ ((S)-AMB-FUBINACA) in pHLM, and from 110 ± 34.5 ((S)-AB-FUBINACA) to 3216 ± 607 mL min⁻¹ kg⁻¹ ((S)-AMB-FUBINACA) in pHHeps. Predicted Human in vivo hepatic clearance (CL_H) ranged from 0.34 ± 0.09 ((S)-AB-FUBINACA) to 17.79 ± 0.20 mL min⁻¹ kg⁻¹ ((S)-5F-AMB-PINACA) in pHLM and 1.39 ± 0.27 ((S)-MDMB-FUBINACA) to 18.25 ± 0.12 mL min⁻¹ kg⁻¹ ((S)-5F-AMB-PINACA) in pHHeps. Valinate and tert-leucinate indole and indazole-3-carboxamide SCRAs are often rapidly metabolised in vitro but are highly protein bound in vivo and therefore predicted in vivo CL_H is much slower than CL_int. This is likely to give rise to longer detection windows of these substances and their metabolites in urine, possibly as a result of accumulation of parent drug in lipid-rich tissues, with redistribution into the circulatory system and subsequent metabolism.

Designer drugs: mechanism of action and adverse effects

Psychoactive substances with chemical structures or pharmacological profiles that are similar to traditional drugs of abuse continue to emerge on the recreational drug market. Internet vendors may at least temporarily sell these so-called designer drugs without adhering to legal statutes or facing legal consequences. Overall, the mechanism of action and adverse effects of designer drugs are similar to traditional drugs of abuse. Stimulants, such as amphetamines and cathinones, primarily interact with monoamine transporters and mostly induce sympathomimetic adverse effects. Agonism at μ-opioid receptors and γ-aminobutyric acid-A (GABAA) or GABAB receptors mediates the pharmacological effects of sedatives, which may induce cardiorespiratory depression. Dissociative designer drugs primarily act as N-methyl-D-aspartate receptor antagonists and pose similar health risks as the medically approved dissociative anesthetic ketamine. The cannabinoid type 1 (CB1) receptor is thought to drive the psychoactive effects of synthetic cannabinoids, which are associated with a less desirable effect profile and more severe adverse effects compared with cannabis. Serotonergic 5-hydroxytryptamine-2A (5-HT2A) receptors mediate alterations of perception and cognition that are induced by serotonergic psychedelics. Because of their novelty, designer drugs may remain undetected by routine drug screening, thus hampering evaluations of adverse effects. Intoxication reports suggest that several designer drugs are used concurrently, posing a high risk for severe adverse effects and even death.

Harmful Effects of Smoking Cannabis: A Cerebrovascular and Neurological Perspective

Apart from being used as a medicine, cannabis or marijuana is the most widely abused recreational drug all over the world. The legalization and decriminalization of cannabis in Canada and various states of USA may be the underlying reason of the widespread popularity of it among young population. Various studies have reported about the relationship between cannabis use and different detrimental effects like cardiovascular, cerebrovascular, and neurological complications among different age groups. Specifically, the young population is getting adversely affected by this, harmful yet, readily accessible recreational drug. Although the mechanism behind cannabis mediated neurological and cerebrovascular complications has not been elucidated yet, the results of these studies have confirmed the association of these diseases with cannabis. Given the lack of comprehensive study relating these harmful complications with cannabis use, the aim of this narrative literature review article is to evaluate and summarize current studies on cannabis consumption and cerebrovascular/neurological diseases along with the leading toxicological mechanisms.

Sociodemographic and clinical characteristics of synthetic cannabinoid users in a large psychiatric emergency department in Turkey

Synthetic cannabinoid (SC) use is a global concern and is creating new challenges for treatment services. Although some studies have been reported, there is a need for further research regarding the sociodemographic and clinical characteristics of SC users so that general and psychiatric emergency departments can provide more effective treatments. We aimed to investigate the sociodemographic and clinical characteristics in a cohort of patients using SC who presented to the psychiatric emergency department of the University of Health Sciences, Istanbul Erenköy Training and Research Hospital for Psychiatry and Neurology (ERSHEAH) in Istanbul, Turkey. This cross-sectional and retrospective medical record review examined 340 SC users who presented to the emergency department of ERSHEAH in a 3-month period. The mean age of the SC users was 26.8 ± 7.5 years and 92.6% were men. Psychotic symptoms were present in 247 SC users (78.8%). Severe intoxication was diagnosed in 26 SC users (7.6%), although SC was detectable in the samples of only 6 patients (13.6%). Impaired consciousness (42.3%) was the most common reason for referral to the general hospital and increased liver enzyme levels (15.9%) were the most common indication in the laboratory findings. We observed that the SC users in our sample presenting as psychiatric emergencies were mostly young men experiencing psychotic symptoms. Determining the sociodemographic and clinical properties of SC users may provide an important contribution to fast recognition and more effective management of acute symptoms of SC users in emergency departments.

Enantiospecific Synthesis, Chiral Separation, and Biological Activity of Four Indazole-3-Carboxamide-Type Synthetic Cannabinoid Receptor Agonists and Their Detection in Seized Drug Samples

Synthetic cannabinoid receptor agonists (SCRAs) have been the largest group of illicit psychoactive substances reported to international monitoring and early warning systems for many years. Carboxamide-type SCRAs are amongst the most prevalent and potent. Enantiospecific synthesis and characterization of four indazole-3-carboxamides, AMB-FUBINACA, AB-FUBINACA, 5F-MDMB-PINACA (5F-ADB), and AB-CHMINACA is reported. The interactions of the compounds with CB1 and CB2 receptors were investigated using a G-protein coupled receptor (GPCR) activation assay based on functional complementation of a split NanoLuc luciferase and EC50 (a measure of potency) and Emax (a measure of efficacy) values determined. All compounds demonstrated higher potency at the CB2 receptor than at the CB1 receptor and (S)-enantiomers had an enhanced potency to both receptors over the (R)-enantiomers. The relative potency of the enantiomers to the CB2 receptor is affected by structural features. The difference was more pronounced for compounds with an amine moiety (AB-FUBINACA and AB-CHMINACA) than those with an ester moiety (AMB-FUBINACA and 5F-MDMB-PINACA). An HPLC method was developed to determine the prevalence of (R)-enantiomers in seized samples. Lux® Amylose-1 [Amylose tris(3,5-dimethylphenylcarbamate)] has the greatest selectivity for the SCRAs with a terminal methyl ester moiety and a Lux® i-Cellulose-5 column for SCRAs with a terminal amide moiety. Optimized isocratic separation methods yielded enantiomer resolution values (Rs) ≥ 1.99. Achiral GC-MS analysis of seized herbal materials (n = 16), found 5F-MDMB-PINACA (<1.0-91.5 mg/g herbal material) and AMB-FUBINACA (15.5-58.5 mg/g herbal material), respectively. EMB-FUBINACA, AMB-CHMICA, 5F-ADB-PINACA isomer 2, and ADB-CHMINACA were also tentatively identified. Analysis using chiral chromatography coupled to photodiode array and quadrupole time of flight mass spectrometry (chiral HPLC-PDA-QToF-MS/MS) confirmed that the (S)-enantiomer predominated in all samples (93.6-99.3% (S)-enantiomer). Small but significant differences in synthesis precursor enantiopurity may provide significant differences between synthesis batches or suppliers and warrants further study. A method to compare potency between samples containing different SCRAs at varying concentrations was developed and applied in this small preliminary study. A 10-fold difference in the "intrinsic" potency of samples in the study was noted. With the known heterogeneity of SCRA infused materials, the approach provides a simplified method for assessing and communicating the risk of their use.

Synthetic Cannabinoid-Associated Multiple Organ Failure: Case Series and Literature Review

OBJECTIVE

We describe a multicenter descriptive case series of six patients admitted with synthetic cannabinoid (SC) intoxication displaying similar symptoms and sequelae, all resulting in multiple organ failure.

METHODS

Patients were included in this report if they presented with known SC use and experienced multiple organ failure between March 1, 2016, and July 19, 2016, to the intensive care units of three hospitals in Maryland. Patients were followed to either discharge or death, and complications related to SC were documented.

RESULTS

All six patients presented with altered mental status and severe rhabdomyolysis, with a peak creatine phosphokinase ranging from 4000 to >320,000 units/L. The majority of patients (five of six) presented with acute kidney injury, with most (four of six) requiring continuous renal replacement therapy. Most patients experienced fever (five of six) and myocardial injury, as evidenced by a troponin elevation (three of six). Seizures occurred in half of patients (three of six patients). Two patients required emergent fasciotomies of the bilateral lower extremities for acute compartment syndrome. Two patients developed fulminant hepatic failure that necessitated liver transplant evaluation, one requiring Molecular Adsorbent Recirculating System (MARS) therapy as a bridge to successful transplant, while the patient without it did not survive. Delirium, severe rhabdomyolysis, acute kidney injury, and fever are common in patients with synthetic cannabinoid intoxication.

CONCLUSIONS

Given the growing abuse of these substances, clinicians should consider their use in the differential of such patient presentations. To our knowledge, only a few published case reports discuss multiple organ failure associated with SC toxicity, and only two have described an associated acute liver failure. Our report describes the first case of SC-associated acute liver failure requiring organ transplantation. Clinicians should be aware of life-threatening complications and consider SC ingestion in the differential diagnosis of patients presenting with multiple organ failure.

Should Cytochrome P450 Inducers be Used to Accelerate Clearance of Brodifacoum from Poisoned Patients?

A recent multi-state outbreak of life-threatening bleeding following inhalation of synthetic cannabinoids has been attributed to contamination with the long-acting anticoagulant rodenticide (LAAR) brodifacoum, a second-generation, highly potent, long-acting derivative of the commonly used blood thinner warfarin. While long-term treatment with high-dose vitamin K1 restores coagulation, it does not affect brodifacoum metabolism or clearance, and, consequently, brodifacoum remains in the human body for several months, thereby predisposing to risk of bleeding recurrence and development of coagulation-independent injury in extrahepatic tissues and fetuses. This has prompted the evaluation of pharmacological measures that accelerate brodifacoum clearance from poisoned patients. Since the induction of certain cytochrome P450 (CYP) enzymes accelerates warfarin metabolism, using CYP inducers, such as phenobarbital, to accelerate brodifacoum clearance seems plausible. However, unlike warfarin, brodifacoum does not undergo significant metabolism in the liver, nor have the effects of phenobarbital on vitamin K1 metabolism been previously determined. In addition, the safety of phenobarbital in brodifacoum-poisoned patients has not been established. Therefore, we propose that CYP inducers should not be used to accelerate the clearance of brodifacoum from poisoned patients, but that alternative approaches such as reducing enterohepatic recirculation of brodifacoum, or using lipid emulsions to scavenge brodifacoum throughout the body, be considered.

Successful resuscitation of prolonged cardiac arrest occurring in association with 'skunk' and toluene toxicity

We report a case of prolonged and successful resuscitation following cardiotoxicity-related arrest occurring after inhaling toluene and Skunk, which is an increasingly popular synthetic cannabinoid (SC). Following presentation to the emergency department because of lethargy, nausea and chest pain, a 28-year-old male user of Skunk and toluene suffered from cardiac arrest due to ventricular fibrillation (VF). Cardiogenic shock, severe metabolic acidosis and regular wide QRS tachycardia were observed in the patient, and he developed VF every 5-10 minutes over the course of 10 hours. The patient responded to prolonged resuscitation and was discharged on 8th day of his admission in a healthy condition. This case report is the first report that cardiac arrest occurring as a result of Skunk and toluene inhalation, which was resolved without sequelae after prolonged resuscitation.

Systematic review of nephrotoxicity of drugs of abuse, 2005-2016

BACKGROUND

The United States is faced with an unprecedented epidemic of drug abuse. Every year thousands of Americans visit the emergency departments all over the country with illicit drug related complaints. These drugs have been known to be associated with a range of renal pathologies, from reversible acute kidney injuries to debilitating irreversible conditions like renal infarction. So far, no comprehensive study or systematic review has been published that includes the commonly used street drugs and designer drugs with potential nephrotoxic outcomes.

METHODS

We conducted a systematic review of published case reports, case series, and cross sectional studies of nephrotoxicities related to drugs of abuse. Literature review was conducted using PubMed/Medline from January 1, 2005 -December 31, 2016 to search for publications related to drug abuse with a defined renal outcome. Publications which reported renal injury in relation to the use of illicit drugs were selected, specifically those cases with raised creatinine levels, clinically symptomatic patients, for instance those with oliguria and proven renal biopsies.

RESULTS

A total of 4798 publications were reviewed during the search process and PRISMA flow chart and Moose protocol regarding systematic reviews were followed. 110 articles were shortlisted for the review. A total of 169 cases from case reports and case series, and 14 case studies were analyzed. Renal manifestations of specific illicit drug abuse were included in this review.

CONCLUSION

Based on the evidence presented, a wide range of renal manifestations were found to be associated with drug abuse. If the trend of increasing use of illicit drug use continues, it will put a significant percentage of the population at an elevated risk for poor renal outcomes. This study is limited by the nature of the literature reviewed being primarily case reports and case series.

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.

Strokes are possible complications of cannabinoids use

It is critically important to identify all factors that may play a role in the recent increase of the incidence of stroke among the young population. Considering the worldwide use of cannabinoids (cannabis and synthetic cannabinoids), the recent legalization of their consumption in some countries, and their supposed involvement in cardiovascular events, we evaluated their role in the occurrence of neurovascular complications among the young. Ninety-eight patients were described in the literature as having a cannabinoids-related stroke (85 after cannabis use and 13 after synthetic cannabinoids). The distribution by type of stroke was as follows: 4 patients with an undetermined type of stroke, 85 with an ischemic stroke and/or a transient ischemic attack, and 9 with a hemorrhagic stroke. The mean age of patients was 32.3±11.8years (range 15-63), and the majority of them were male with a sex ratio of 3.7:1. Cannabis was often smoked with tobacco in 66% of cases. Most of the patients with cannabinoids-related strokes were chronic cannabis users in 81% of cases, and for 18% of them, there was a recent increase of the amount of cannabis consumption during the days before the occurrence of stroke. Even if the prognosis of stroke was globally favorable in 46% of cases, with no or few sequelae, 5 patients died after the neurovascular event. One striking element reported in the majority of the reports was a temporal relationship between cannabinoids use, whether natural or synthetic, and the occurrence of stroke. However, a temporal correlation does not mean causation, and other factors may be involved. Cannabis may be considered as a risk factor of stroke until research shows evidence of an underlying mechanism that, alone or in association with others, contributes to the development of stroke. As of today, reversible cerebral vasoconstriction triggered by cannabinoids use may be a convincing mechanism of stroke in 27% of cases. Indeed, despite the widespread use of cannabinoids, the low frequency of neurovascular complications after their use may be due to a genetic predisposition to their neurovascular toxicity in some individuals. Further studies should focus on this point. More importantly however, this low frequency may be underestimated because the drug consumption may not be systematically researched, neither by questioning nor by laboratory screening. Besides this vascular role of cannabinoids in the occurrence of stroke, a cellular effect of cannabis on brain mitochondria was recently suggested in an experimental study. One of the mechanisms involved in young cannabis users with stroke may be the generation of reactive oxygen species leading to an oxidative stress, which is a known mechanism in stroke in humans. It is useful to inform the young population about the real potential risk of using cannabinoids. We suggest to systematically ask all young adults with stroke about their drug consumption including cannabinoids, to screen urine for cannabis or to include a specific diagnostic test to detect synthetic cannabinoids, and to obtain non-invasive intracranial arterial investigations (i.e. CT-angiography or cerebral MRA) in order to search for cerebral vasoconstriction. However, several questions remained unresolved and further research is still needed to assess the pathophysiological mechanisms involved in young cannabinoids users with stroke. This article is part of a Special Issue entitled "Cannabinoids and Epilepsy".

Health and Social Care workers' perceptions of NPS use in Northern Ireland

BACKGROUND

The EU Early Warning System currently monitors more than 560 new psychoactive substances, far outweighing the total number of illicit drugs under international control. Due to the recent emergence of NPS and rapidly changing nature of the market, evidence about the way in which the emerging drugs are managed in health and social care settings is limited.

METHODS

The study adopted a mixed methods design, utilising a cross sectional survey and telephone interviews to capture data from staff working in drug and alcohol related services in statutory and voluntary sectors, across the five Health and Social Care (HSC) Trust areas in Northern Ireland. 196 staff participated in the survey and 13 participated in follow up in telephone interviews between August and November 2015.

RESULTS

Study respondents reported that addressing NPS related issues with service users was a key aspect of their daily role and function. Levels of injecting behaviours were also viewed as relatively high by study participants. Almost all workers used harm reduction as their primary approach when working with service users and the majority of respondents called for additional practical training in relation to addressing drug interactions and intervening with NPS related issues.