Cannabis has long been used as a treatment for a variety of illness for centuries. From arthritis to post-traumatic stress disorder (PTSD), medical marijuana offers relief to millions of patients across the world. As more states and countries legalize cannabis for recreational or medical purposes, research on the plant has also increased. A recent study found that medical marijuana may be a great treatment for people suffering from a variety of mental health issues.

The study, published in the journal Clinical Psychology Review, found evidence that cannabis can likely benefit people dealing with depression, social anxiety and PTSD. There have been arguments both for and against medical marijuana for people with mental health issues, but the research done by the Canadian and American team is a definite win for proponents of legalization.

“This is a substance that has potential use for mental health,” says Zach Walsh, an associate professor of psychology at the University of British Columbia. “We should be looking at it in the same way [as other drugs] and be holding it up to the same standard.”

Authors of the study hope that the findings will lead to further consideration of medical marijuana as a viable treatment for mental health issues. Currently, another promising study is underway on the efficacy of cannabis for veterans with combat-related PTSD. Because marijuana is still considered illegal on the federal level, millions of veterans suffering from the illness cannot access the plant due to Veterans Affairs policy.

Research also suggested that cannabis may have a place in dealing with addiction. “We are really excited about the potential substitution effect,” says Professor Walsh. “If people use cannabis as a replacement for opioid medications, or to get off of opioids or cut back, we could see some pretty dramatic public health benefits. The level of opioid overdoses is so high right now.”

Despite marijuana’s shown efficacy in alleviating certain mental health disorders, bipolar is not one of them. Researchers found that patients who had been diagnosed as bipolar showed more negative effects than positive ones. This is an important distinction as it may help doctors and scientists down the road develop more insight as to how cannabinoids react with the brain’s chemistry. Walsh added that just like any other drug, more research must be conducted before making further treatment recommendations.