Anti–inflammatory properties may be the key.
Cannabinoids contain anti–inflammatory properties that could make them useful in the treatment of a wide–range of skin diseases, according to researchers at the University of Colorado Anschutz Medical Campus.

The new study, published online recently in the Journal of the American Academy of Dermatology, summarizes the current literature on the subject and concludes that pharmaceuticals containing cannabinoids may be effective against eczema, psoriasis, atopic and contact dermatitis.

Currently, 28 states allow comprehensive medical cannabis programs with close to 1 in 10 adult cannabis users in the U.S. utilizing the drug for medical reasons. As researchers examine the drug for use in treating nausea, chronic pain and anorexia, more and more dermatologists are looking into its ability to fight a range of skin disease.

“Perhaps the most promising role for cannabinoids is in the treatment of itch,” said the study’s senior author Dr. Robert Dellavalle, MD, associate professor of dermatology at the University of Colorado School of Medicine.

He noted that in one study, eight of 21 patients who applied a cannabinoid cream twice a day for three weeks completely eliminated severe itching or pruritus. The drug may have reduced the dry skin that gave rise to the itch. Dellavalle believes the primary driver in these cannabinoid treatments could be their anti–inflammatory properties. In the studies he and his fellow researchers reviewed, they found that THC (tetrahydrocannabinol) the active ingredient in marijuana, reduced swelling and inflammation in mice.

At the same time, mice with melanoma saw significant inhibition of tumor growth when injected with THC.

“These are topical cannabinoid drugs with little or no psychotropic effect that can be used for skin disease,” Dellavalle said.

Still, he cautioned that most of these studies are based on laboratory models and large–scale clinical trials have not been performed. That may change as more and more states legalize cannabis.

Dellavalle said for those who have used other medications for itch and skin disease without success, trying a cannabinoid is a viable option especially if it has no psychotropic effect. He did not recommend such medications for cancer based on current evidence.

“These diseases cause a lot of problems for people and have a direct impact on their quality of life,” he said. “The treatments are currently being bought over the internet and we need to educate dermatologists and patients about the potential uses of them.”