From USA TODAY.

Cannabis is widely known as a recreational drug, illegal in some states and legal in others. But what do you know about cannabis-based therapies, often referred to as medical marijuana? For well over a century, compounds extracted from the marijuana plant, of which there are more than 500, have been used therapeutically for a range of medical applications, from treating anxiety to addressing pain. So where are all the clinical trials, and why are doctors still unable to prescribe medical cannabis? Dr. Staci Gruber, director of the Marijuana Investigations for Neuroscientific Discovery at McLean Hospital and associate professor of psychiatry at Harvard Medical School, joins USA TODAY’s The Excerpt to discuss the current state of medical cannabis and CBD research.

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