Medical cannabis for the treatment of insomnia

Insomnia is highly prevalent and associated with substantial individual and societal burden, while existing pharmacological treatments are limited by adverse effects and concerns about long-term use. The role of medical cannabis in the treatment of insomnia remains unclear because of limited and heterogeneous evidence. Despite increasing clinical use, current guidelines do not provide clear recommendations due to uncertainty regarding its efficacy and safety. A clear synthesis of available evidence is needed to inform patients, clinicians, and policymakers about the potential benefits and harms of medical cannabis for insomnia.

To assess the benefits and harms of medical cannabis in adults with insomnia.

We used CENTRAL, MEDLINE, Embase, Global Index Medicus, and two trial registers, together with reference checking, citation searching, and contacting study authors, to identify studies for inclusion in the review. The latest search date was 5 April 2025.

We included parallel randomized controlled trials (RCTs), cross-over RCTs, and cluster RCTs in adult participants with any type of insomnia comparing medical cannabis with placebo, benzodiazepine receptor agonists, benzodiazepines, melatonin receptor agonists, antidepressants, and antipsychotics. We excluded studies that were quasi-RCTs and studies using experimental and unregistered drugs, cannabis receptor antagonists and negative allosteric modulators like rimonabant, as well as modulators that enhance endocannabinoid system activity, such as fatty acid amide hydrolase inhibitors, and synthetic cannabis, like levonantradol.