It has been known that the human endocannabinoid system (ECS) modulates cutaneous biology. Receptors from the ECS have been identified in the skin, and systemic misuse/abuse of synthetic cannabinoids has also been associated with the manifestation of dermatological disorders, indicating the effects of the ECS on skin biology. Preclinical evidence suggests topical application of CBD products may be beneficial for skin disorders such as eczema, psoriasis, pruritis, and inflammatory conditions. However, confirmed clinical efficacy and the underlying molecular mechanisms of CBD on cosmetic improvement have yet to be fully identified. Research indicates that both Cannabinoid 1 (CB1) and Cannabinoid 2 (CB2) receptors are found in epidermal keratinocytes, cutaneous nerve fibers, dermal cells, melanocytes, eccrine sweat glands, and hair follicles. Endocannabinoids are involved in various dermatological functions, such as formation and maintenance of the skin barrier, cell growth, and cell differentiation, as well as immunological and inflammatory processes.
Because the ECS plays an important regulatory function in the skin, it is reasonable to suggest that treatment with topical cannabinoids could be efficacious for certain disorders, or for skin health in general. Not surprisingly, there is lacking research investigating the therapeutic potential for topical applications of cannabinoids. Historically, there is evidence to suggest applying CBD topically may be a viable route of administration for certain skin conditions. For example, researchers previously investigated the efficacy of topically applied CBD (1–10%) in a gel format, specifically for reduction of inflammation-associated symptoms in a monoarthritic rat model, and found that it was well absorbed - the plasma concentration directly correlated with the dose applied (dose-dependent reaction). As of 2020, no clinical trials investigating the topical absorptive capability of CBD in humans have been identified. Further work is warranted to better understand the appropriate doses and delivery methods for therapeutic CBD skin applications. The authors of this study conclude that while there is absolutely potential for CBD in the treatment of acne, seborrhea, eczema/dermatitis, and skin barrier function is promising, larger and more structured studies are needed to fully validate its efficacy.
Resources:
1) Baswan SM, Klosner AE, Glynn K, et al. Therapeutic Potential of Cannabidiol (CBD) for Skin Health and Disorders. Clin Cosmet Investig Dermatol. 2020;13:927-942. Published 2020 Dec 8. doi:10.2147/CCID.S286411