New research is being conducted on the effects of cannabis on skin conditions such as including pruritus (severe itching), inflammatory skin disease, and skin cancer.
One small study showed that application of a cannabinoid containing cream reduced itching in 38% of chronic kidney disease patients on dialysis. Another small study demonstrated that a cream activating cannabinoid receptors in the body (see the endocannabinoid system) reduced itching by 86%.
It is further thought that cannabinoids can have a positive effect on keratinocyte proliferation, which is a thickening or multiplying of epidermal cells. Epidermal cell production is normally tightly controlled within the body, however with skin diseases such as psoriasis, production can go awry and out of control resulting in pathological epidermal hyperplasia (thickening). The processes that govern and regulate epidermal growth are critically relevant for understanding how drugs can have a relevant effect on addressing various skin diseases associated with hyperplasia.
Separately, in a 2015 study, mice with chemically induced melanoma treated with subcutaneously injected THC demonstrated significant inhibition of tumor growth. Human studies need to be conducted to take this research further. “Although cannabinoids may have anti-inflammatory and antitumor effects, further clinical research is needed before they can be used for these purposes clinically.”
The role of cannabinoids in dermatology – https://www.jaad.org/article/S0190-9622(17)30308-0/pdf