Last week, the Public Health Service announced that they would approve a University of Arizona study on the use of marijuana for Post-Traumatic Stress Disorder.

With this announcement, it seems that the marijuana plant is heading into unknown territory – federally-supported research examining its possible benefits.

But, is this really new territory? Yes and no.

It is true that the inhabitants (chemicals called cannabinoids) of the marijuana plant have been utilized in federally-funded research for decades. Synthesized from the plant itself, or developed as synthetic versions of the real thing, cannabinoids have been studied in labs across the world, and developed into medications such as Marinol (synthetic THC).

Indeed, we have research to support the role of cannabinoids in aiding sleep, decreasing pain, reducing spasticity, acting as a neuro-protectant, an antioxidant, and implicated as a possible treatment for cancer, MS, epilepsy, arthritis, Alzheimer’s and Parkinson’s. In fact, the government holds patents on several cannabinoids for a variety of symptoms and ailments.

So, if the government has invested in the notion that marijuana has medicinal qualities, then why is the approval of this study such big news? Unlike research using isolated and synthetic cannabinoids, this is the first time that the whole plant has been invited to the party.

Opponents of medical marijuana claim that the road of isolated and synthetic cannabinoids is the proper channel for bringing marijuana to market as a medicine. However, numerous research studies, as well as Dr. Sanjay Gupta in his recent CNN special speak to the importance of the entourage effect, which means that having multiple cannabinoids working in tandem, no matter how little of each is in the plant, is more effective than isolating individual cannabinoids.

Indeed, Sativex, the sublingual spray developed to treat cancer and MS, is formulated from the entire plant, not just individual cannabinoids. A version of Sativex, high in CBD, is undergoing clinical trials in the US for childhood epilepsy.

For the first time, the federal government is opening the door for research on the benefits of using the whole cannabis plant. This newly approved study in Arizona will use the whole plant to study the impact of its use on Post-Traumatic Stress Disorder. This particular study has been waiting for this approval for over 20 years. The Schedule I status of marijuana creates almost insurmountable barriers to getting federal approval for research.

And, complicating the issue is that, among other Schedule I drugs, marijuana is the only one that holds the requirement that the marijuana used for research must come from the federal government and cannot be contracted out to a private source. Therefore, although the Arizona study had approval from the University and the FDA, the feds refused to hand over the marijuana - until now.

Hopefully the research from Dr. Sue Sisley and her team at Arizona will pave the way for a new era of whole plant research.

Amanda Reiman is a policy manager for the Drug Policy Alliance.

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