Both types of cannabinoid receptors have been found throughout the structure of human skin. The role of the endocannabinoid system in skin is thought to regulate cell growth, wound healing and the differentiation of keratinocytes, the cells that make up the different skin layers. Since the endocannabinoid system plays a large part in the immune response, cannabis medicine as treatment for inflammatory skin conditions has been the focus of recent research.1
There is evidence that allergic skin conditions, such as contact dermatitis, can be lessened by targeting the endocannabinoid system.2 Pruritis, the unpleasant sensation of itchiness that leads to excessive scratching, can be difficult to treat. A study of 2,500 patients with allergic eczema showed topical treatment with a cream containing the cannabinoid N-palmithylethanolamide (PEA) significantly decreased symptoms and was well tolerated. Resolution of pruritis occurred in 38%, with significant improvement in a further 41% of the patients.3 Three other studies using creams containing the same and additional cannabinoids found similar findings, with resolution or significant reduction of symptoms without any adverse side effects.4,5,6
Anti-tumor effects have been documented for malignant cancers of the skin.7 Melanoma cells have been found to express both cannabinoid receptors, and studies have shown the use of cannabinoids decreased the number of viable melanoma cells in the laboratory.8 Cannabinoid receptors are also expressed in benign papillomas and in malignant squamous cell carcinomas.9 Malignant tumors treated with cannabinoids showed inhibition of growth, increased apoptotic cells (dying cells) and impaired blood flow.10
Patients are using topical cannabis preparations for inflammatory skin conditions, pain, pruritis and skin tumors. Some patients use other delivery methods as well, with sublingual CBD-rich oils for inflammation and inhaled THC for quick relief of pruritis being the most common. The terpenoids β-caryophyllene and pinene are both anti-inflammatory and should be included for enhanced results.
Kupczyk, Piotr, Adam Reich, and Jacek C. Szepietowski. “Cannabinoid system in the skin–a possible target for future therapies in dermatology.” Experimental dermatology 18.8 (2009): 669-679.
Karsak, Meliha, et al. “Attenuation of allergic contact dermatitis through the endocannabinoid system.” science 316.5830 (2007): 1494-1497.
Eberlein, B., et al. “Adjuvant treatment of atopic eczema: assessment of an emollient containing N‐palmitoylethanolamine (ATOPA study).” Journal of the European Academy of Dermatology and Venereology 22.1 (2008): 73-82.
C Szepietowski, Jacek. “Efficacy and tolerance of the cream containing structured physiological lipids with endocannabinoids in the treatment of uremic pruritus: a preliminary study.” Acta Dermatovenerologica Croatica 13.2 (2005): 0-0.
Szepietowski, Jacek C., Adam Reich, and Tomasz Szepietowski. “Emollients with endocannabinoids in the treatment of uremic pruritus: discussion of the therapeutic options.” Therapeutic Apheresis and Dialysis 9.3 (2005): 277-279.
Stander, S., et al. “Topical cannabinoid agonist. An effective new possibility for treating chronic pruritis." Hautarzt (2006): 57: 801-807.
Sarfaraz, Sami, et al. “Cannabinoids for cancer treatment: progress and promise.” Cancer research 68.2 (2008): 339-342.
Blázquez, Cristina, et al. “Cannabinoid receptors as novel targets for the treatment of melanoma.” The FASEB journal 20.14 (2006): 2633-2635.
Casanova, M. Llanos, et al. “Inhibition of skin tumor growth and angiogenesis in vivo by activation of cannabinoid receptors.” Journal of Clinical Investigation 111.1 (2003): 43.
Ibid.