Marijuana for Mental Health: Rising Use Despite Weak Evidence and Growing Risks

Marijuana use for mental health treatment is on the rise, despite limited evidence of its effectiveness. A recent review found no strong proof that cannabis helps with anxiety, depression, or PTSD. Meanwhile, concerns grow over its risks, particularly for young users and those with mood disorders.

Nearly one in four people aged 16 to 65 in the US and Canada have used marijuana for medical reasons. Half of these users turn to it for mental health issues, even though research does not support its benefits for conditions like anorexia, bipolar disorder, or schizophrenia.

Regular cannabis use—especially during pregnancy, adolescence, or young adulthood—can disrupt brain development. It also raises the risk of self-harm in individuals with mood disorders. The rise of high-potency products, containing up to 35% THC, and concentrates with up to 80% THC, has further increased addiction rates. Currently, about 30% of US marijuana users show signs of cannabis use disorder. As of March 2026, 40 US states have legalised medical cannabis. However, it remains unclear how many explicitly permit its use for mental health treatment or what criteria apply. Established treatments, such as SSRIs and cognitive behavioural therapy, continue to be the recommended options for these conditions.

While marijuana remains widely used for mental health, scientific backing for its benefits is lacking. The risks, particularly for vulnerable groups, are well-documented. Proven therapies like SSRIs and CBT remain the standard for managing mental health disorders.