The differential effects of medicinal cannabis on mental health: A systematic review

Nora de Bode; Emese Kroon; Sharon R Sznitman; Janna Cousijn

doi:10.1016/j.cpr.2025.102581

The differential effects of medicinal cannabis on mental health: A systematic review

Clin Psychol Rev. 2025 Mar 29:118:102581. doi: 10.1016/j.cpr.2025.102581. Online ahead of print.

Authors

Nora de Bode¹, Emese Kroon², Sharon R Sznitman³, Janna Cousijn²

Affiliations

¹ Neuroscience of Addiction Lab, Center for Substance Use and Addiction Research, Department of Psychology, Education & Child Studies, Erasmus School of Social and Behavioral Sciences, Erasmus University Rotterdam, the Netherlands. Electronic address: debode@essb.eur.nl.
² Neuroscience of Addiction Lab, Center for Substance Use and Addiction Research, Department of Psychology, Education & Child Studies, Erasmus School of Social and Behavioral Sciences, Erasmus University Rotterdam, the Netherlands.
³ School of Public Health, University of Haifa, Israel; Institute of Primary Health Care (BIHAM), University of Bern, Switzerland.

PMID: 40186931
DOI: 10.1016/j.cpr.2025.102581

Abstract

The use of medicinal cannabis to improve mental health is increasing globally, both in clinical settings and through self-medication. This involves a variety of products containing ∆9-tetrahydrocannabinol (THC), cannabidiol (CBD), THC + CBD combinations, or derivatives. This review provides an up-to-date overview of the positive and negative effects of medicinal cannabis on mental health diagnoses and related symptoms of the Diagnostic and Statistical Manual of Mental Disorders 5th Edition. Searches in PubMed, PsycInfo, Embase, and the Cochrane Library (October 2023 and July 2024) identified 18,341 studies, of which 49 controlled studies from 15 different countries were included. All studies focused on treatment-seeking participants using medicinal cannabis for (symptoms of) their mental health diagnosis. Included diagnoses were anxiety disorders, tic disorders, autism spectrum disorder, attention-deficit hyperactivity disorder, obsessive-compulsive disorders, anorexia nervosa, schizophrenia, psychosis, substance use disorders, insomnia, and bipolar disorders. Varying product compositions showed different effects. Most consistently, high doses of CBD were followed by some acute relief in anxiety, while CBD + THC combinations alleviated withdrawal in cannabis use disorder and improved sleep. In clinical trials, THC was associated most with dose-dependent adverse events and, in some cases, deterioration of primary study outcomes, e.g., in psychosis. In naturalistic studies, participants who used THC reported symptom improvement following usage. Risks of bias across studies were prevalent, and no study found long-lasting medicinal effects or improvement. Overall, medicinal cannabis may provide short-term relief for certain symptoms but is not a cure or without mental health risks.

Keywords: Cannabinoids; Controlled studies; DSM-5; Medicinal cannabis; Mental health.

Publication types

Review