Exposure to cannabinoids can lead to persistent cognitive and psychiatric disorders

Cannabidiol for treatment of Irritability and Aggressive Behavior in Children and Adolescents with ASD: Background and Methods of the CAnnabidiol Study in Children with Autism Spectrum DisordEr (CASCADE) Study

Introduction

Autism spectrum disorder (ASD) is a neurodevelopmental disorder commonly associated with behavioral challenges. There are few evidence based pharmacological interventions available for the treatment of behavioral symptoms associated with ASD. Cannabidiol (CBD), the non-psychoactive component of cannabis, has potential neuroprotective, antiepileptic, anxiolytic, and antipsychotic effects and may be useful in treating the behavioral symptoms of ASD.

Methods

We describe the research methods of a 27-week double-blind placebo-controlled cross-over trial of cannabidiol for the treatment of irritability and aggression associated with ASD, utilizing the irritability subscale of the Aberrant Behavior Checklist-2nd edition (ABC-2) as the primary outcome measure. Adverse effects and safety monitoring protocols are included. Several secondary and exploratory outcomes measures also include anxiety, communication, repetitive behaviors, attention, hyperactivity, autism family experience, and telehealth functional behavior assessment.

Conclusion

There is a significant need for clinical research exploring alternative medications for the treatment of behavioral symptoms of ASD. Cannabidiol (CBD) is being studied for the management of irritability, aggression, and other problem behaviors associated with ASD.

Use of Medical Cannabis in Patients with Gilles de la Tourette's Syndrome in a Real-World Setting

Objective: Tourette's syndrome (TS) is a neurodevelopmental disorder characterized by vocal and motor tics and other comorbidities. Clinical recommendations for the use of medical cannabis are established, yet further guidance is needed. The aim of this study was to describe the experience of patients with TS with medical cannabis. Materials and Methods: TS patients were recruited from a registry of patients ("Tikun Olam" company). Questionnaires were answered before and after 6 months of treatment. Patients were divided into two groups: (A) patients who responded and (B) patients who did not respond to the follow-up questionnaire. In group A, an analysis was made to evaluate the presence and frequency of motor and vocal tics. The patients' general mood, employment status, quality of life, and comorbidities were also included in the analysis. Results: Seventy patients were identified. The tetrahydrocannabinol and cannabidiol mean daily dose was 123 and 50.5 mg, respectively. In group A, a statistically significant improvement was identified in quality of life (p<0.005), employment status (p=0.027), and in the reduction of the number of medications (p<0.005). Sixty-seven percent and 89% of patients with obsessive-compulsive disorder and anxiety comorbidities, respectively, reported an improvement. No statistically significant improvement was identified in motor tics (p=0.375), vocal tics (p>0.999), tics frequency (p=0.062), or general mood (p=0.129). The most frequent adverse effects were dizziness (n=4) and increased appetite (n=3). Conclusion: Subjective reports from TS patients suggest that medical cannabis may improve their quality of life and comorbidities. More studies are needed to evaluate the efficacy and safety of medical cannabis. Registry in the MOH: https://www.moh.gov.sg/ (Trial number: 0185-19-ASF).

Cannabis use disorder contributes to cognitive dysfunction in Veterans with traumatic brain injury

Background

While emerging evidence supports a link between traumatic brain injury (TBI) and progressive cognitive dysfunction in Veterans, there is insufficient information on the impact of cannabis use disorder (CUD) on long-term cognitive disorders. This study aimed to examine the incidences of cognitive disorders in Veterans with TBI and CUD and to evaluate their relationship.

Methods

This retrospective cohort study used the US Department of Veterans Affairs and Department of Defense administrative data from the Long-term Impact of Military-Relevant Brain Injury Consortium-Chronic Effects of Neurotrauma Consortium Phenotype study. Diagnoses suggesting cognitive disorders after a TBI index date were identified using inpatient and outpatient data from 2003 to 2022. We compared the differential cognitive disorders incidence in Veterans who had the following: (1) no CUD or TBI (control group), (2) CUD only, (3) TBI only, and (4) comorbid CUD+TBI. Kaplan-Meier analyses were used to estimate the overall cognitive disorders incidence in the above study groups. The crude and adjusted Cox proportional hazards models were used to estimate crude and adjusted hazard ratios (HRs) for cognitive disorders.

Results

A total of 1,560,556 Veterans [82.32% male, median (IQR) age at the time of TBI, 34.51 (11.29) years, and 61.35% white] were evaluated. The cognitive disorder incidence rates were estimated as 0.68 (95% CI, 0.62, 0.75) for CUD only and 1.03 (95% CI, 1.00, 1.06) for TBI only per 10,000 person-months of observations, with the highest estimated cognitive disorder incidence observed in participants with both TBI and CUD [1.83 (95% CI, 1.72, 1.95)]. Relative to the control group, the highest hazard of cognitive disorders was observed in Veterans with CUD+TBI [hazard ratio (HR), 3.26; 95% CI, 2.91, 3.65], followed by those with TBI only (2.32; 95 CI%, 2.13, 2.53) and with CUD (1.79; 95 CI%, 1.60, 2.00). Of note, in the CUD only subgroup, we also observed the highest risk of an early onset cognitive disorder other than Alzheimer's disease and Frontotemporal dementia.

Discussion

The results of this analysis suggest that individuals with comorbid TBI and CUD may be at increased risk for early onset cognitive disorders, including dementia.

A Placebo-Controlled Trial of Cannabinoid Treatment for Disruptive Behavior in Children and Adolescents with Autism Spectrum Disorder: Effects on Sleep Parameters as Measured by the CSHQ

Autism spectrum disorder (ASD) is often associated with debilitating sleep disturbances. While anecdotal evidence suggests the positive effect of cannabinoids, randomized studies are lacking. Here, we report the effects of cannabinoid treatment on the sleep of 150 children and adolescents with ASD, as part of a double-blind, placebo-controlled study that assessed the impact of cannabinoid treatment on behavior (NCT02956226). Participants were randomly assigned to one of the following three treatments: (1) whole-plant cannabis extract, containing cannabidiol (CBD) and Δ9-Tetrahydrocannabinol (THC) in a 20:1 ratio, (2) purified CBD and THC extract in the same ratio, and (3) an oral placebo. After 12 weeks of treatment (Period 1) and a 4-week washout period, participants crossed over to a predetermined, second 12-week treatment (Period 2). Sleep disturbances were assessed using the Children’s Sleep-Habit Questionnaire (CSHQ). We found that the CBD-rich cannabinoid treatment was not superior to the placebo treatment in all aspects of sleep measured by the CSHQ, including bedtime resistance, sleep-onset delay, and sleep duration. Notably, regardless of the treatment (cannabinoids or placebo), improvements in the CSHQ total score were associated with improvements in the autistic core symptoms, as indicated by the Social Responsiveness Scale total scores (Period 1: r = 0.266, p = 0.008; Period 2: r = 0.309, p = 0.004). While this study failed to demonstrate that sleep improvements were higher with cannabinoids than they were with the placebo treatment, further studies are required.

Adolescent THC exposure: effects on pain-related, exploratory, and consummatory behaviors in adult male vs. female rats

RATIONALE

Adolescent cannabinoid exposure has been shown to alter cognitive, reward-related, and motor behaviors as well as mesocorticolimbic dopamine (DA) function in adult animals. Pain is also influenced by mesocorticolimbic DA function, but it is not known whether pain or cannabinoid analgesia in adults is altered by early exposure to cannabinoids.

OBJECTIVE

To determine whether adolescent Δ⁹-tetrahydrocannabinol (THC) exposure alters pain-related behaviors before and after induction of persistent inflammatory pain, and whether it influences antinociceptive of THC, in adult rats, and to compare the impact of adolescent THC exposure on pain to its effects on known DA-dependent behaviors such as exploration and consumption of a sweet solution.

METHODS

Vehicle or THC (2.5 to 10 mg/kg s.c.) was administered daily to male and female rats on post-natal day (PND) 30-43. In adulthood (PND 80-88), sensitivity to mechanical and thermal stimuli before and after intraplantar injection of complete Freund's adjuvant (CFA) was determined. Antinociceptive, exploratory, and consummatory effects of 2.0 mg/kg THC were then examined.

RESULTS

Adolescent THC exposure did not significantly alter adult sensitivity to non-noxious or noxious stimuli either before or after CFA injection, nor did it alter the antinociceptive effect of THC. In contrast, adolescent THC exposure altered adult exploratory and consummatory behaviors in a sex-dependent manner: when tested as adults, adolescent THC-treated males showed less hedonic drinking than adolescent vehicle-treated males, and females but not males that had been THC-exposed as adolescents showed reduced sensitivity to THC-induced suppression of activity and THC-induced hedonic drinking as adults.

CONCLUSIONS

Adolescent THC exposure that altered both exploratory and consummatory behaviors in adults did not alter pain-related behaviors either before or after induction of inflammatory pain, suggesting that cannabinoid exposure during adolescence is not likely to substantially alter pain or cannabinoid analgesia in adulthood.

Gender Differences in Dual Diagnoses Associated with Cannabis Use: A Review

Gender differences in psychiatric disorders and drug use are well known. Cannabis is the most widely used illegal drug among young people. In recent years, its use has been related to the development of psychiatric pathologies; however, few studies have incorporated the gender perspective as of yet. The present work analyses the literature to determine the existence of gender differences in the development of psychotic, depressive and anxious symptoms associated with cannabis use. First, we describe cannabis misuse and its consequences, paying special attention to adolescent subjects. Second, the main gender differences in psychiatric disorders, such as psychosis, depression, anxiety and cannabis use disorders, are enumerated. Subsequently, we discuss the studies that have evaluated gender differences in the association between cannabis use and the appearance of psychotic, depressive and anxious symptoms; moreover, we consider the possible explanations for the identified gender differences. In conclusion, the studies referred to in this review reveal the existence of gender differences in psychiatric symptoms associated with cannabis use, although the direction of such differences is not always clear. Future research is necessary to discern the causal relationship between cannabis use and the development of psychiatric symptoms, as well as the gender differences found.

Pharmacokinetics, Safety, and Tolerability of a Medicinal Cannabis Formulation in Patients with Chronic Non-cancer Pain on Long-Term High Dose Opioid Analgesia: A Pilot Study

INTRODUCTION

This phase I open-label study examined pharmacokinetics, safety, and tolerability of escalating doses of a novel combination cannabinoid medication (1:1 tetrahydrocannabinol [THC]/cannabidiol [CBD]) in patients with chronic non-cancer pain (CNCP) on high dose opioid analgesia.

METHODS

Nine people with CNCP and oral morphine equivalent daily dose of 60 mg or higher were recruited. Blood concentrations of THC, 11-hydroxytetrahydrocannabinol (OH-THC), 11-nor-9-carboxy-tetrahydrocannabinol (COOH-THC), and CBD were assayed weekly. Concentrations were measured after a single dose of 2.5 mg THC/2.5 mg CBD on day 1, and daily escalating doses up to a single dose of 12.5 mg THC/12.5 mg CBD on day 29. Follow-up was on day 36 after a 7-day washout. Secondary outcome data encompassed pain, mood, and sleep parameters.

RESULTS

The parent compounds THC, and CBD, and metabolites OH-THC and COOH-THC were detected at most time points. In general, the concentration of all analytes increased until 2 h post-administration, decreasing to approximately pre-dose concentrations by 8 h. There was considerable inter- and intra-individual variability. The study medication was well tolerated. Eight participants reported at least one adverse event (AE), with a total of 62 AEs; most common were euphoric mood, headache, and agitation, none classified as severe. There was no significant change to pain severity self-ratings, nor use of pain medications. Improvements in pain interference scores, mood, and some sleep parameters were observed.

CONCLUSION

The THC/CBD formulation was tolerated well in a group of patients with CNCP. Between-participant variability supports personalized dosing and "start low-go slow" titration. To validate and quantify improvements in secondary efficacy outcomes a randomized placebo-controlled study is needed.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Register (CT-2019-CTN-01224-1).

Prevalence and associated risk factors of cannabinoid abuse among Egyptian university students: a cross-sectional study

Global surveys have highlighted rise in consumption of cannabinoids among residents of both developed and developing countries. Cannabinoids cause severe damage to the cardiovascular, nervous, respiratory, and renal systems, and have been linked with several deaths. Despite these adverse health effects, the use of cannabinoids has rapidly increased. This work seeks to estimate the prevalence of cannabinoid abuse among Egyptian university students and explore the associated risk factors. A cross-sectional study was carried out over 3 months (1st of July-1st of October 2020) and included 2380 students. Participants were subjected to a pre-designed self-administered questionnaire that included demographic data, Addiction Severity Index, and Depression Anxiety Stress Scale. Among the participating students, 4.9% of them reported cannabinoid abuse and 41% reported smoking cigarettes. The most used substances were hashish (96.5%), Strox (41.3%), Bhang (34.4%), voodoo (34.4%), and Tramadol (31.1%). Gender and social status were also significantly related to rates of substances abuse; most illicit drug users were males (93.1%), and the majority was of low (41.3%) or moderate (50.8%) socioeconomic status. The most significant risk factors associated with substance use were positive history of family conflict (OR=6.48; CI95%: 5.08-8.64, p<0.001), encouragement by peers (OR=2.95; CI95%: 1.73-5.05, p<0.001), male gender (OR=5.46; CI95%: 2.40-12.44, p=0.001), positive history of child abuse (OR=2.85; CI95%: 1.96-3.04, p=0.001), having a stay-at-home mother (OR= 1.56, CI95%: 1.19-2.04, p=0.001), living in an urban area (OR=2.22; CI95%: 1.53-5.0, p=0.002), and positive family history of substance use (OR=1.98; CI95%: 1.48-2.08, p=0.045). This study emphasizes the possible significant rise in substance use among university students. Awareness campaigns should target both students and student families.

l-Theanine Prevents Long-Term Affective and Cognitive Side Effects of Adolescent Δ-9-Tetrahydrocannabinol Exposure and Blocks Associated Molecular and Neuronal Abnormalities in the Mesocorticolimbic Circuitry

Chronic adolescent exposure to Δ-9-tetrahydrocannabinol (THC) is linked to elevated neuropsychiatric risk and induces neuronal, molecular and behavioral abnormalities resembling neuropsychiatric endophenotypes. Previous evidence has revealed that the mesocorticolimbic circuitry, including the prefrontal cortex (PFC) and mesolimbic dopamine (DA) pathway are particularly susceptible to THC-induced pathologic alterations, including dysregulation of DAergic activity states, loss of PFC GABAergic inhibitory control and affective and cognitive abnormalities. There are currently limited pharmacological intervention strategies capable of preventing THC-induced neuropathological adaptations. l-Theanine is an amino acid analog of l-glutamate and l-glutamine derived from various plant sources, including green tea leaves. l-Theanine has previously been shown to modulate levels of GABA, DA, and glutamate in various neural regions and to possess neuroprotective properties. Using a preclinical model of adolescent THC exposure in male rats, we report that l-theanine pretreatment before adolescent THC exposure is capable of preventing long-term, THC-induced dysregulation of both PFC and VTA DAergic activity states, a neuroprotective effect that persists into adulthood. In addition, pretreatment with l-theanine blocked THC-induced downregulation of local GSK-3 (glycogen synthase kinase 3) and Akt signaling pathways directly in the PFC, two biomarkers previously associated with cannabis-related psychiatric risk and subcortical DAergic dysregulation. Finally, l-theanine powerfully blocked the development of both affective and cognitive abnormalities commonly associated with adolescent THC exposure, further demonstrating functional and long-term neuroprotective effects of l-theanine in the mesocorticolimbic system.SIGNIFICANCE STATEMENT With the increasing trend of cannabis legalization and consumption during adolescence, it is essential to expand knowledge on the potential effects of adolescent cannabis exposure on brain development and identify potential pharmacological strategies to minimize Δ-9-tetrahydrocannabinol (THC)-induced neuropathology. Previous evidence demonstrates that adolescent THC exposure induces long-lasting affective and cognitive abnormalities, mesocorticolimbic dysregulation, and schizophrenia-like molecular biomarkers that persist into adulthood. We demonstrate for the first time that l-theanine, an amino acid analog of l-glutamate and l-glutamine, is capable of preventing long-term THC side effects. l-Theanine prevented the development of THC-induced behavioral aberrations, blocked cortical downregulation of local GSK-3 (glycogen synthase kinase 3) and Akt signaling pathways, and normalized dysregulation of both PFC and VTA DAergic activity, demonstrating powerful and functional neuroprotective effects against THC-induced developmental neuropathology.

Do Adolescent Exposure to Cannabinoids and Early Adverse Experience Interact to Increase the Risk of Psychiatric Disorders: Evidence from Rodent Models

There have been growing concerns about the protracted effects of cannabis use in adolescents on emotion and cognition outcomes, motivated by evidence of growing cannabis use in adolescents, evidence linking cannabis use to various psychiatric disorders, and the increasingly perceived notion that cannabis is harmless. At the same time, studies suggest that cannabinoids may have therapeutic potential against the impacts of stress on the brain and behavior, and that young people sometimes use cannabinoids to alleviate feelings of depression and anxiety (i.e., “self-medication”). Exposure to early adverse life events may predispose individuals to developing psychopathology in adulthood, leading researchers to study the causality between early life factors and cognitive and emotional outcomes in rodent models and to probe the underlying mechanisms. In this review, we aim to better understand the long-term effects of cannabinoids administered in sensitive developmental periods (mainly adolescence) in rodent models of early life stress. We suggest that the effects of cannabinoids on emotional and cognitive function may vary between different sensitive developmental periods. This could potentially affect decisions regarding the use of cannabinoids in clinical settings during the early stages of development and could raise questions regarding educating the public as to potential risks associated with cannabis use.

Psychiatric Disorders and Cannabinoid Receptors

With the increasing global use of medical and adult recreational use of cannabis and cannabinoids, this chapter provides overview of evidence from animal and human studies on psychiatric disorders and cannabinoid receptors. We review and present evaluation of the relationship between changes in the ECS and psychiatric disorders. Evidence suggests the existence of a relationship between changes in components of the ECS, and some of the symptoms present in psychiatric disorders. Both CB1Rs and CB2Rs are components of the endocannabinoid system with different cellular and tissue localization patterns that are differentially expressed in the CNS and PNS and are emerging targets for the treatment of number psychiatric disorders. As cannabis preparations are widely used for recreation globally, it is predictable that cannabis use disorders (CUDs) will increase and there is currently no available treatment for CUDs. Although major advances have been reported from cannabinoid and ECS research, there are gaps in scientific knowledge on long-term consequences of cannabis use. Adolescent and cannabis use during pregnancy presents further challenges, and more research will uncover the signaling pathways that couple the gut microbiota with the host ECS. Development of cannabis and cannabinoid nanomedicine for nanotherapy will certainly overcome some of the shortcomings and challenges in medicinal and recreational use of cannabis and cannabinoids. Thus, nanotechnology will allow targeted delivery of cannabinoid formulations with the potential to elevate their use to scientifically validated nanotherapeutic applications as the field of cannabis nanoscience matures.

Risk factors associated with driving under the influence of drugs in the USA

BACKGROUND

Driving under the influence of drugs (DUID) is a burgeoning public health concern in the USA. Because little is known about individuals who engage in DUID, the purpose of this study was to analyse potential sociodemographic characteristics and behavioural risk factors associated with the behaviour.

METHODS

Self-reported data from drivers ≥18 years of age who ever used drugs and participated in the 2018 National Survey on Drug Use and Health were used. Characteristics of those who reported to engage and not engage in DUID were compared via frequencies, percentages and logistic regression analyses, which accounted for the multistage survey design.

RESULTS

Among eligible respondents, 10.4% (weighted n=117 275 154) reported DUID. DUID was higher among those aged 18-25 year (34%), males (65%), unmarried individuals (61%), lesbian/gay/bisexuals (13%), those whom abused or were drug dependent (45%), engaged in numerous risky lifestyle behaviours (12%) and those taking medication for a mental health issue (22%). Nearly 20% and 6% of respondents engaged in DUID abused or were dependent on marijuana or methamphetamine, respectively. The adjusted odds of DUID were greatest among those 18-25 years of age (OR 3.7; 95% CI 2.8 to 5.0), those never/not married (OR 1.8; 95% CI 1.5 to 2.2), those who abused or were drug dependent (OR 4.0; 95% CI 3.5 to 4.7), exhibited riskier lifestyle behaviours (OR 8.0; 95% CI 5.9 to 11.0), were employed (OR 1.3; 95% CI 1.1 to 1.6) or lesbian/gay/bisexuals (OR 1.4; 95% CI 1.1 to 1.7).

CONCLUSIONS

DUID was common among some population sub-groups who may benefit from intervention.

[Neurodevelopment and cannabis]

Brain development is a complex phenomenon, stretching from fetal life to adolescence, during which brain maturation proceeds through a series of ordered events including critical periods of plasticity. The brain is particularly sensitive to the environment during these changes. The endocannabinoid system participates directly and indirectly in these plasticity and maturation processes. The main psychoactive component of cannabis, the delta-9-tetrahydrocanabinol, can cross the placental barrier, is present in breastmilk and diffuses in the brain. It interacts with the endocannabinoid signaling, especially through the activation of cannabinoid receptors 1 CB1R, which can lead to abnormal neurodevelopmental processes and neuronal circuits functions. Therefore, exposure to cannabis in utero, in perinatal phase, as well as during the adolescence disrupts the brain maturation and can cause disturbances on the cognitive, psychotic and addictive levels that persist far beyond the period of exposure. Several factors modulate the risk of such complications, but studies performed in animal models as well as in human cohorts have shown that exposure during both the critical perinatal and adolescence phases is a risk factor per se. Current knowledge encourages the dissemination of objective information to young people, to prevent and limit early exposure and its consequences.

Barriers to the wider adoption of medicinal Cannabis

The use of Cannabis-based preparations for medicinal use has waxed and waned in the multi-millennial history of human co-existence with the plant and its cultivation. Recorded use of preparations from Cannabis is effectively as old as recorded history with examples from China, India and Ancient Egypt. Prohibition and restriction of availability allowed a number of alternatives to take the place of Cannabis preparations. However, there has been a worldwide resurgence in medicinal Cannabis advocacy from the public. Media interest has been piqued by particular evocative cases. Altogether, therefore, there is pressure on healthcare professionals to prescribe and dispense Cannabis-based preparations. This review enunciates some of the barriers which are slowing the wider adoption of medicinal Cannabis.

S-adenosyl-l-methionine (SAMe), cannabidiol (CBD), and kratom in psychiatric disorders: Clinical and mechanistic considerations

Given the limitations of prescription antidepressants, many individuals have turned to natural remedies for the management of their mood disorders. We review three selected natural remedies that may be of potential use as treatments for depressive disorders and other psychiatric or neurological conditions. The best studied and best supported of these three remedies is S-adenosyl-l-methionine (SAMe), a methyl donor with a wide range of physiological functions in the human organism. With the increasing legalization of cannabis-related products, cannabidiol (CBD) has gained popularity for various potential indications and has even obtained approval in the United States and Canada for certain neurological conditions. Kratom, while potentially useful for certain individuals with psychiatric disorders, is perhaps the most controversial of the three remedies, in view of its greater potential for abuse and dependence. For each remedy, we will review indications, doses and delivery systems, potential anti-inflammatory and immunomodulatory action, adverse effects, and will provide recommendations for clinicians who may be considering prescribing these remedies in their practice.

Medical Cannabis in Children

The use of medical cannabis in children is rapidly growing. While robust evidence currently exists only for pure cannabidiol (CBD) to treat specific types of refractory epilepsy, in most cases, artisanal strains of CBD-rich medical cannabis are being used to treat children with various types of refractory epilepsy or irritability associated with autism spectrum disorder (ASD). Other common pediatric disorders that are being considered for cannabis treatment are Tourette syndrome and spasticity. As recreational cannabis use during youth is associated with serious adverse events and medical cannabis use is believed to have a relatively high placebo effect, decisions to use medical cannabis during childhood and adolescence should be made with caution and based on evidence. This review summarizes the current evidence for safety, tolerability, and efficacy of medical cannabis in children with epilepsy and in children with ASD. The main risks associated with use of Δ9-tetrahydrocannabinol (THC) and CBD in the pediatric population are described, as well as the debate regarding the use of whole-plant extract to retain a possible "entourage effect" as opposed to pure cannabinoids that are more standardized and reproducible.

Adverse events following cannabis for medical use in Tuscany: An analysis of the Italian Phytovigilance database

AIMS

Despite a significant increase in using cannabis for medical purposes, current evidence on its safety in real-world clinical practice is still poorly characterised. By a case-by-case analysis of spontaneous reports of suspected adverse events (AEs) collected in Tuscany within the Italian Phytovigilance database, the aim of the present study was to describe AEs occurred in patients exposed to medical cannabis.

METHODS

We evaluated all reports of cannabis-related suspected AEs collected within the Phytovigilance database up to December 2018. Information regarding cannabis therapy, patient's demographic and clinical characteristics, concomitant medications, AE description according to the Medical Dictionary for Regulatory Activities (MedDRA) classification, AE seriousness and AE outcome, were collected. The causality assessment was performed following World Health Organisation-Uppsala Monitoring Centre criteria.

RESULTS

Fifty-three cannabis-related AE reports were analysed. The majority of patients were females (77.3%), with a mean age of 61.9 years. Thirty-nine (73.6%) cases were defined as nonserious and the majority of them (86.9%) showed a complete resolution or improvement. Forty-six (86.8%) cases were judged as probably related to cannabis consumption. The most frequently reported system organ class was psychiatric and nervous system disorders, and a potential drug-drug interaction was present in 16 cases.

CONCLUSION

Cannabis was generally well tolerated and the majority of AEs were mild and transient. Our analysis highlighted important safety issues for clinical practice, in particular the need for an accurate prescription monitoring during the titration phase, particularly in the presence of concomitant medications.

[Progress in cannabis research from a pharmaceutical chemist's point of view]

Preparations of hemp, Cannabis sativa, have been used for thousands of years as recreational and therapeutic drugs. The most important constituents are the psychoactive (-)-trans-∆⁹-tetrahydrocannabinol (THC), a partial agonist at cannabinoid (CB) receptors CB₁ and CB₂, and the non-psychoactive pleiotropic cannabidiol (CBD). Both compounds are highly lipophilic, like the endogenous CB receptor agonists, the arachidonic acid derivatives anandamide and arachidonoyl glycerol. The CB receptors belong to the family of G protein-coupled receptors, and the first X‑ray crystal structures of both CB receptors subtypes have recently been obtained, which will facilitate the rational design of novel synthetic ligands. Besides the already largely established indications such as chronic pain, chemotherapy-induced vomiting, multiple sclerosis-associated spasms, and cachexia, there is preliminary evidence for several further cannabinoid effects, which will have to be confirmed by clinical studies.