Dermatology-Related Uses of Medical Cannabis Promoted by Dispensaries in Canada, Europe, and the United States.

There is a growing interest in the use of medical cannabis for a variety of dermatologic conditions. Despite the lack of evidence to validate the effectiveness and safety of marijuana, it is approved to treat a variety of dermatologic conditions in the United States. Furthermore, medical cannabis dispensaries have been making unsubstantiated claims about medical cannabis. It is important for dermatologists to know about the purported use of medical cannabis to help patients navigate this new treatment option, particularly as cannabis becomes legal in Canada in October 2018. We collected and tabulated the dermatologic indications for medical cannabis from Canada, the United States, and Europe. In the United States, dermatologic-approved indications vary by state but include psoriasis, lupus, nail-patella syndrome, and severe pain. Health Canada has listed psoriasis, dermatitis, and pruritus as potential therapeutic uses for cannabis but does not endorse its use for therapeutic purposes. We also surveyed the websites of dispensaries in Canada, the United States, and Europe and found that numerous unsubstantiated claims were being made and advertised to consumers. Dermatologic uses of medical cannabis, as claimed by dispensaries, included treating acne, aging, allergic contact dermatitis, chronic pain, herpes, dermatitis, lupus, Lyme disease, nevi, psoriasis, epidermolysis bullosa, and melanoma. Psoriasis, dermatitis, and chronic pain were the most commonly cited indications for medical cannabis listed by dispensaries. Our data indicate that the suggested and advertised uses of medical cannabis are largely unsubstantiated. Further research is necessary to validate the indications, effectiveness, and safety of medical cannabis.