No evidence cannabis helps anxiety, depression, or PTSD

The largest review of medicinal cannabis to date, published in The Lancet by University of Sydney researchers, found no evidence that cannabis effectively treats anxiety, depression, or PTSD despite widespread use for those conditions. Researchers warn it may worsen mental health by increasing risks of psychosis and cannabis use disorder while delaying proven treatments. Limited and low-quality evidence suggested possible benefits for insomnia, autism, and Tourette's syndrome.