Comprehensive evidence map finds medical cannabis most effective for pain, spasticity, and seizures

Of 489 descriptions of treatment effects across 71 health outcomes, 278 (57%) reported positive or potentially positive effects. When limited to high-quality systematic reviews (AMSTAR 2), 42 of 67 treatment descriptions (63%) across 20 outcomes were positive or potentially positive. Top outcomes: pain, insomnia, seizures, anxiety, muscle spasticity, MS symptoms, urinary incontinence, anorexia, and patient safety.

Systematic evidence mapping of 194 studies selected from 1,840 initial references, using two independent blinded researchers and Rayyan screening software. Quality assessed with AMSTAR 2.

This is one of the most comprehensive evidence maps of medical cannabis to date, covering 71 distinct health outcomes. It moves beyond condition-by-condition reviews to show the full landscape of where cannabis medicine has demonstrated benefit.

Policy debates about medical cannabis often rely on cherry-picked studies. This evidence map provides a structured, comprehensive view showing that while evidence is strongest for pain and neurological conditions, positive signals exist across a much wider range of health outcomes.

Evidence maps identify and categorize evidence but do not meta-analyze effect sizes. Quality varies widely across included studies. Cannabis formulations and doses vary enormously.