Cannabidiol, a non-psychotropic substance found in marijuana, may actually prevent an eye condition that leads to an all-too-common complication of diabetes. The complication, of course, is diabetic retinopathy.

It's the growth of abnormal, excess blood vessels in the eye that leads to retinopathy. But Gregory Liou, Ph.D., of the Medical College of Georgia has found that cannabidiol can prevent this from happening. His study, which was published in the American Journal of Pathology and reported by United Press International, found that cannabidiol had the ability to dramatically reduce oxidative stress in rats with diabetes. Cannabidiol also decreased the levels of certain factors which are key in the development of retinopathy. And the substance prevented the blood vessels from leaking into the retina and the death of retinal cells.  

It's not the first time researchers have looked at cannabis plant extracts as an ingredient for a medication to help diabetes. In the United Kingdom, professor Mike Cawthorne is working with GW Pharma, a specialist developer of cannabis-based medications, to come up with plant-based medicines that would treat diabetes.

While marijuana contains between 60 and 70 cannabinoid extracts, just one (THC) has the psychoactive properties that are usually linked with the plant. Now the GW Metabolic Research Laboratory is examining the various cannabinoid molecules that have been discovered in the cannabis plant, with the idea of coming up with medications.

Hawthorne had led the team that developed a drug called Avandia, GlaxoSmithKline's second biggest selling drug until 2007, when a study linking it to a higher risk of heart attacks caused the sales to plummet.

"I sincerely believe it is possible to improve on it (Avandia), and plant based medicines could be one way to do that," Cawthorne told Reuters.

Cawthorne, who is recognized as a leading authority in the research of new treatments for both obesity and type 2 diabetes, told Reuters that he's doing his research with actual cannabis extract, not the synthetic equivalent. The GW Metabolic Research Laboratory is hoping to create a medication that would treat specific symptoms of diabetes, like non-alcoholic fatty liver, according to Reuters.

"There really have been relatively few developments in finding new diabetes drug treatments," Cawthorne told Reuters. "This new approach might be more productive in answering the unmet clinical need."

Needless to say, don't expect to see marijuana-based meds out there anytime soon. Amy Fischl, RD, of the Kovler Diabetes Center at University of Chicago Medical Center, says nothing is anywhere close to being ready for approval by the Federal Food and Drug Administration.

"There are some studies being done, but nothing is really in the works yet," Fischl said.


Liou, Gregory. "Cannabidiol compound may protect against diabetic retinopathy." American Journal of Pathology 168 (1): 235-244, 2006.), reprinted in Forecast, the publication of the American Diabete Association."

 "Scientist: Marijuana May Treat Diabetes." Reuters. 17 June 2009.,2933,526853,00.html?sPage=fnc/health/diabetes