Review Finds No Evidence Cannabis Treats Anxiety, Depression, PTSD

A new systematic review has found no evidence that medicinal cannabis effectively treats anxiety, depression or post-traumatic stress disorder, despite its widespread prescription for these conditions in Australia and the United States. Researchers from the University of Sydney analyzed 54 randomized controlled trials spanning 1980 to 2025 and published their results in Lancet Psychiatry on Tuesday.

The study examined oral formulations of cannabis products, including those containing cannabidiol (CBD) and tetrahydrocannabinol (THC). Lead author Dr. Jack Wilson, a postdoctoral research fellow at the university's Matilda Centre for Research in Mental Health and Substance Use, stated that the review revealed no benefits for these core mental health issues, nor for anorexia nervosa, bipolar disorder, obsessive-compulsive disorder or psychotic disorders like schizophrenia. "A lot of people find their cannabis to be effective for their condition, and that is great," Wilson said. "But when we look at the evidence as a whole, it's just really not there yet to justify the routine use of these medicines for mental health disorders."

In Australia, where medicinal cannabis was legalized in...