Cannabinoids is a class of chemicals found in cannabis which is derived from the plant Cannabis sativa whose dried leaves are used for marijuana. Marijuana is the most commonly used illicit drug in the United States. Approximately 1 in 10 adult cannabis users in the U.S. use it for medical purposes (Blanco C, et al. Use of marijuana for medical purposes among adults in the United States. JAMA 2017;317:2019-211).
Cannabinoids may be an effective topical treatment for skin diseases such as severe itching, contact dermatitis, atopic dermatitis, and psoriasis. With the increase in medical cannabis legalization (to date 28 states and the District of Columbia) in the United States it is important to understand the drug’s health benefits. There are over 10,000 scientific studies on cannabis and cannabis-derived products and there has been evidence that cannabis treats chronic pain, nausea, anorexia, and spasticity. The possible therapeutic use of cannabis in dermatology is quite interesting; researchers have been investigating its use for itching, melanoma, and inflammatory skin disease. Dr Robert Dellavalle and colleagues from the University of Colorado School of Medicine reviewed the existing evidence (Mounessa, et al. The role of cannabinoids in dermatology. JAAD 2017 S0190-9622(17)30308-0).
In one study 21 adults who had itching applied a cannabinoid cream twice daily for 3 weeks. There was complete elimination of itching in 38% of patients (1). Another study showed 86.4% reduction in itching (2). Anti-inflammatory properties might explain its benefits for allergic contact dermatitis and atopic dermatitis. In psoriasis inhibiting keratinocyte proliferation may be the mechanism by which cannabinoids are beneficial (3). Studies in mice showed anti-tumor effects on melanoma and keratinocyte carcinoma (4).
There is a promising role for cannabinoids for dermatology for its anti-inflammatory and antitumor effects but more clinical research is needed in the form of large-scale clinical trials. Although topical cannabinoids can be found on the internet it would be prudent to speak to a dermatologist before self-treating.
- Szepietowski JC et al. Efficacy and tolerance of the cream containing structured physiological lips with endocannabinoids in the treatment of uremic pruritus; a preliminary study. Acta Dermatolvenerolgica Croatica. 2005;13:97-103.
- Stander et al. Topical cannabinoid agonists; an effective new possibility for treating chronic pruritus. Der Hautarzt. 2006;57:801-807.
- Wilkinson JD et al. Cannabinoids inhibit human keratinocyte proliferation through a non-CB1/CB2 mechanism and have a potential therapeutic value in the treatment of psoriasis. J Dermatolog Sci. 2007;45:87-92.
- Soliman et al. Cannabinoids as therapeutics for non-melanoma and melanoma skin cancer. J Dermatol Clin Res. 2016;4:1-7.