Cannabis and Mental Health Treatment: What Does the Research Show?
Researchers conducted a review of the scientific literature to determine if using cannabis helped treat mental health problems. They identified 15 articles, divided by the type of mental health condition and form of cannabis used as a treatment.
Overall, they found:
No clear benefits: Evidence is too limited and uncertain to support cannabis as a treatment for conditions like post‑traumatic stress disorder, anxiety, depression, or ADHD.
Some possible small benefit: A few studies suggest cannabidiol (CBD) alone might reduce anxiety in people with anxiety disorders, but the evidence is still weak.
Risks are real: THC‑dominant cannabis can worsen mania in bipolar disorder and increase psychotic symptoms in people with psychosis.
Addiction risk: About 3 in 10 people who use cannabis in the past year develop cannabis use disorder, and half of these have moderate or severe problems with negative impact on social, employment, and other adverse outcomes.
High‑THC products in young people: Regular use is linked to a 2-11 times higher risk of psychosis, higher addiction risk, and self‑harm in mood disorders.
Conclusion:
The review concludes there is not enough evidence to recommend cannabis in the treatment of mental health conditions, and there are potential harms. These harms include worsening mental illness and addiction. High-risk groups are cautioned to avoid using cannabis, including adolescents, young adults, people with bipolar or psychotic disorders, pregnant women, and those at risk of substance use disorders. Before using cannabis, people should speak with a knowledgeable healthcare provider.
The Article
Kansagara, D., Terry, G. E., Ayers, C. K., & D'Souza, D. C. (2026). Cannabis and Mental Health: A Review. JAMA internal medicine, 186(5), 618–628. https://doi.org/10.1001/jamainternmed.2025.8215
