Introduction Cannabis is the most common recreational drug worldwide and synthetic cannabinoid receptor agonists are currently the largest group of new psychoactive substances. The aim of this study was to compare the clinical features and outcomes of lone acute cannabis toxicity with lone acute synthetic cannabinoid receptor agonist toxicity in a large series of presentations to European emergency departments between 2013-2020. Methods Self-reported drug exposure, clinical, and outcome data were extracted from the European Drug Emergencies Network Plus which is a surveillance network that records data on drug-related emergency department presentations to 36 centres in 24 European countries. Cannabis exposure was considered the control in all analyses. To compare the lone cannabis and lone synthetic cannabinoid receptor agonist groups, univariate analysis using chi squared testing was used for categorical variables and non-parametric Mann-Whitney U- testing for continuous variables. Statistical significance was defined as a P value of < 0.05. Results Between 2013-2020 there were 54,314 drug related presentations of which 2,657 were lone cannabis exposures and 503 lone synthetic cannabinoid receptor agonist exposures. Synthetic cannabinoid receptor agonist presentations had statistically significantly higher rates of drowsiness, coma, agitation, seizures and bradycardia at the time of presentation. Cannabis presentations were significantly more likely to have palpitations, chest pain, hypertension, tachycardia, anxiety, vomiting and headache. Discussion Emergency department presentations involving lone synthetic cannabinoid receptor agonist exposures were more likely to have neuropsychiatric features and be admitted to a psychiatric ward, and lone cannabis exposures were more likely to have cardiovascular features. Previous studies have shown variability in the acute toxicity of synthetic cannabinoid receptor agonists compared with cannabis but there is little comparative data available on lone exposures. There is limited direct comparison in the current literature between lone synthetic cannabinoid receptor agonist and lone cannabis exposure, with only two previous poison centre series and two clinical series. Whilst this study is limited by self-report being used to identify the drug(s) involved in the presentations, previous studies have demonstrated that self-report is reliable in emergency department presentations with acute drug toxicity. Conclusion This study directly compares presentations with acute drug toxicity related to the lone use of cannabis or synthetic cannabinoid receptor agonists. It supports previous findings of increased neuropsychiatric toxicity from synthetic cannabinoid receptor agonists compared to cannabis and provides further data on cardiovascular toxicity in lone cannabis use.

In 2020, fentanyl and its analogs contributed to ~65% of drug-attributed fatalities in the USA, with a threatening increasing trend during the last ten years. These synthetic opioids used as potent analgesics in human and veterinary medicine have been diverted to recreational aims, illegally produced and sold. Like all opioids, central nervous system depression resulting from overdose or misuse of fentanyl analogs is characterized clinically by the onset of consciousness impairment, pinpoint miosis and bradypnea. However, contrasting with what observed with most opioids, thoracic rigidity may occur rapidly with fentanyl analogs, contributing to increasing the risk of death in the absence of immediate life support. Various mechanisms have been proposed to explain this particularity associated with fentanyl analogs, including the activation of noradrenergic and glutamatergic coerulospinal neurons and dopaminergic basal ganglia neurons. Due to the high affinities to the mu-opioid receptor, the need for more elevated naloxone doses than usually required in morphine overdose to reverse the neurorespiratory depression induced by fentanyl analogs has been questioned. This review on the neurorespiratory toxicity of fentanyl and analogs highlights the need for specific research focused on these agents to better understand the involved mechanisms of toxicity and develop dedicated strategies to limit the resulting fatalities.

Abstract Background The revised Opioid Risk Tool (ORT-OUD) is a brief, self-report scale designed to provide clinicians with a simple, validated method to screen for the risk of developing an Opioid Use Disorder (OUD) in patients without a prior history of substance abuse. This study aimed to translate and validate the Arabic version of ORT-OUD in the Lebanese population and assess its clinical validity in a sample of patients with OUD. Methods This cross-sectional study in the Lebanese population used several validated scales to assess the risk of OUD, including the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST). Other tools evaluated chronotype and sleep and mood disturbances. Principal component analysis with Varimax rotation was applied to assess ORT-OUD construct validity. Convergent validity with the Arabic version of ASSIST was evaluated. The ORT-OUD criterion validity was then assessed in a clinical sample of patients with OUD. Results This study included 581 participants. The prevalence of the OUD risk in the Lebanese population using the ORT-OUD scale and the ASSIST-opioids scale was estimated at 14.5% and 6.54%, respectively. No items of the ORT-OUD were removed; all items converged over a solution of four factors with an eigenvalue > 1, explaining a total of 68.2% of the variance (Cronbach’s alpha = 0.648). The correlation coefficients between the ORT-OUD total score and ASSIST subscales were as follows: ASSIST-opioids (r = 0.174; p = < 0.001), ASSIST-sedatives (r = 0.249; p < 0.001), and ASSIST-alcohol (r = 0.161; p = < 0.001). ORT-OUD clinical validation showed a correlation with ASSIST-opioids (r = 0.251; p = 0.093) and ASSIST-sedatives (r = 0.598; p < 0.001). Higher ORT-OUD scores were associated with a family and personal history of alcohol and substance consumption and higher insomnia and anxiety scores. Conclusions This study is the first to validate the Arabic version of ORT-OUD in the Lebanese population, an essential step towards improving the detection and management of OUD in this population.

Aim: Explore the possible association between clinical factors and genetic variants of the dopamine pathways and negative symptoms. Materials & methods: Negative symptoms were assessed in 206 patients with schizophrenia using the Arabic version of the self-evaluation of negative symptoms scale and the Positive and Negative Syndrome Scale. Genotyping for COMT, DRD2, MTHFR and OPRM1 genes was performed. Results: Multivariable analysis showed that higher self-evaluation of negative symptoms scale scores were significantly associated with higher age, higher chlorpromazine-equivalent daily dose for typical antipsychotics and in married patients. Higher negative Positive and Negative Syndrome Scale scores were significantly associated with women and having the CT genotype for MTHFR c.677C>T (β = 4.25; p = 0.008) compared with CC patients. Conclusion: Understanding both clinical/genetic factors could help improve the treatment of patients.

The self-evaluation of negative symptoms scale (SNS) is a new easy-to-use self-administered questionnaire allowing clinicians to understand the clinical and genetic factors affecting the negative symptoms in patients with schizophrenia. There was a need to translate and validate this scale in Arabic so that Arab-speaking patients benefit from it. Therefore, the aim of our study was to validate the Arabic version of the SNS in a sample of Lebanese patients with schizophrenia. The Arabic SNS was used to quantify the disability associated with negative symptoms in patients with schizophrenia (n = 206). Six weeks after completing the SNS, the participants were interviewed again to assess test-retest reproducibility. The validity was confirmed by factor analyses using the principal component analysis technique with a varimax rotation. The Positive and Negative Syndrome Scale (PANSS) was also assessed. None of the items of the SNS scale were removed; all items converged over a solution of five factors that had an eigenvalue > 1, explaining a total of 66.01% of the variance (Cronbach’s alpha = 0.879; test part). The mean total SNS score was 17.33 ± 8.43 for the “test”, and 16.35 ± 7.50 for the “retest”. The correlation coefficients between the SNS total score and the PANSS scale and subscales were as follows: total PANSS (r = 0.044; p = 0.530), positive PANSS score (r = − 0.106; p = 0.131), negative PANSS score (r = 0.204; p = 0.003), and general psychopathological PANSS score (r = 0.03; p = 0.530). This study is the first to validate the Arabic version of the SNS in patients with schizophrenia. Using this scale would help improve treatment by correctly assessing negative symptoms, thus optimizing treatment options.