Cannabinoids and Autism Spectrum Disorder: a systematic review

Abstract

Introduction: Autism Spectrum Disorder (ASD) is a neurodevelopment disorder characterized by social communication/interaction deficits, and restrictive, repetitive behaviour patterns, interests, or activities. This disorder is also associated with numerous comorbidities that impact patients' daily life, and the current treatment for these patients based on symptom management remains unsatisfactory. Methods: We performed our systematic review on the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE/PubMed, Web of Science, Scopus, SciELO, clinicaltrials.gov, clinicaltrialsregister.eu and anzctr.org.au. We included randomized-controlled trials, observational studies, case-reports, and ongoing trials reporting patients with ASD as main diagnostic treated with any documented cannabinoid drug, and there was no outcome restriction. Results: Out of eight-hundred and forty-five (n = 845) initial returned articles, we included eighteen studies (n = 18) and thirteen (n = 13) ongoing trials. The included studies suggested that cannabinoids can reduce the intensity and/or number of different symptoms (behavior and sleep problems, hyperactivity, seizures, and others), and may allow reduction of concomitant use of other psychiatric medications, with mostly mild/mild-moderate adverse effects. Conclusion: Cannabinoids are emerging with promising benefits to ASD patients, and this systematic review suggested positive effects in primary and secondary symptoms (mainly behavioral and sleep problems, epilepsy, and hyperactivity), with low incidence of severe adverse events. Future placebo-controlled RCTs are needed to reinforce these benefits and to address the limitations found, so the use of cannabinoids can be expanded to ASD as already on other clinical conditions.