Path of Science: International Electronic Scientific Journal

Mental disorders such as posttraumatic stress disorder (PTSD), psychosis, anxiety, and attention-deficit/hyperactivity disorder (ADHD) are significant global health burdens. While conventional pharmacotherapies and psychotherapies offer symptom relief, up to one-third of patients exhibit inadequate response or intolerable side effects, prompting the exploration of alternative or adjunctive treatments.

The researchers conducted a comprehensive literature search in January 2024 across PubMed, Scopus, and EBSCOhost. They screened peer-reviewed studies published in English between 2014 and 2023, using predefined eligibility criteria. The team extracted data using Cochrane-based templates and performed quality assessments with the RoB 2 tool for randomised trials and the Newcastle-Ottawa Scale for observational studies. Finally, they conducted a narrative synthesis based on diagnostic categories.

The researchers included ten studies—nine randomised controlled trials and one observational study—that examined cannabinoid interventions in PTSD, psychosis-spectrum disorders, ADHD, and social anxiety. Cannabidiol (CBD) was the most commonly studied compound. Neurobiological improvements were consistently observed in psychosis and PTSD, while clinical symptom reduction was more evident in social anxiety and ADHD. Although findings were heterogeneous, CBD demonstrated favourable safety across all studies, with mild or no adverse effects reported.

CBD appears to be safe and shows therapeutic promise in certain psychiatric conditions, particularly for neurobiological modulation in psychosis and PTSD, symptom reduction in social anxiety, and behavioural improvements in adult ADHD. However, evidence remains preliminary. Standardised, large-scale trials are needed to confirm efficacy, refine dosing, and guide clinical use.

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