Topical and transdermal cannabinoid products are used with increasing frequency to address certain dermatological conditions, inflammation in deeper tissues, and issues occurring throughout the body. Topical and transdermal formulations are both applied to the skin, though their mechanisms of action are different. Topical cannabinoid products provide local relief and are limited in activity to the upper layers of the skin, whereas transdermal products are formulated to overcome the dermis and achieve a greater systemic effect . This article focuses on topical applications of hemp-sourced cannabinoids, primarily cannabidiol (CBD), for use in the treatment of dermatological conditions.
The Role of the ECS in Skin Health
There are two types of receptors in our body’s Endogenous Cannabinoid System (ECS): CB1 and CB2. These two receptor types are located throughout the body in varying concentrations. Since the discovery of the endocannabinoid system, it has been indicated that, based on receptor abundance, CB1 receptors are primarily located and active within the central nervous system, whereas CB2 receptors are primarily located and active within the peripheral nervous system, immune system, and digestive system. Research has also indicated that the ECS also plays an important role in the integumentary system (comprising your skin, hair, nails, and glands). CB1 and CB2 receptors, endocannabinoids, and complementary enzymes have been identified in the cells and tissues of the skin and are thought to help facilitate skin barrier formation and maintain homeostasis .
There are numerous endocannabinoids present in the skin, but the most studied are anandamide (AEA) and 2-arachidonoyl glycerol (2-AG). In addition to interacting with cannabinoid receptors, these endocannabinoids have been shown to interact with non-cannabinoid receptors, such as peroxisome proliferator-activated receptors (PPAR) and Transient Receptor Potential receptors (TRP), to assist with a wide variety of functions in the skin2. These functions include skin barrier maintenance and formation, cell growth and differentiation, inflammation and immune response, and pain signaling.
Given the presence and function of endocannabinoids and ECS activity within the skin, it is plausible that cannabinoid therapy applied via the skin will be an efficacious approach applicable to a variety of skin conditions. Clinical research into all methods of cannabinoid therapy are lacking due to historical regulatory barriers, but this is especially the case for topical and transdermal formulations, despite significant benefits such as bypassing of first-pass metabolism and lack of psychotropic effect.
CBD and Common Skin Disorders
Abnormal skin conditions and disorders are common and range from acute to chronic, painful to inconspicuous, and circumstantial to genetic. Almost everyone will experience some sort of abnormal skin reaction at some point in their lives. Topical and systemic steroids, enzyme inhibitors, antibiotics, and antihistamines are frequently prescribed for common dermatological conditions such as acne, eczema, and skin infection. These drug types can cause unwanted side effects, pose added health risks, or partially treat the condition . Dermatological conditions are usually non-fatal but can significantly impair quality of life for many people. Patients with these conditions would benefit from a treatment option that not only mitigates symptoms, but also restores a healthy balance of skin functioning. Cannabinoids can sometimes be the catalyst to restore that balance.
In a small retrospective study conducted in 2019, researchers examined topical CBD-ointment as a treatment option for inflammatory skin diseases and cutaneous resultant scars . The sample group included 20 individuals suffering from psoriasis, atopic dermatitis, or scarring as a result of either of these conditions. Participants self-administered CBD ointment containing no THC twice daily for a continued duration of three months. Measurements in the form of skin evaluations, clinical questionnaires, and photographic comparisons were used to determine the efficacy of treatment and the associated impact on quality of life. Investigators concluded that CBD was effective at treating symptoms and improving skin elasticity and hydration without causing irritation or adverse effects. 
A recent review conducted by researchers at the University of Miami School of Medicine examined available and relevant clinical data pertaining to the treatment of acne with CBD. They concluded that CBD reduced acne symptoms and further prevented excessive inflammation signaling . The researchers strongly recommended further clinical efforts to validate their findings.
Safety of Cannabinoid-Containing Hemp Products
While the outcomes have been positive with few negative effects, the early regulation status of consumer and therapeutic hemp products warrant sufficient caution when recommending and consuming these products. The FDA recommends that hemp producers follow accepted drug development principles, such as routine residual, microbial, and purity testing for all of their products as well as pharmaceutical grade packaging . However, official standardization practices are not currently enacted outside of maximum allowed THC content.
Patients and consumers alike should be fully aware of the source, cannabinoid profile, and purity of the contents to ensure they are receiving a quality product. Lab results from an ISO-certified lab are the only way to verify the accuracy of a product label and ensure the absence of unapproved additives or dangerous contaminants. Topical products rich in cannabinoids are not created equal. The markets are still young, and state by state regulations vary. Some states have no regulations for manufacturing cannabis-extract products. If you want to try such products, the consumer must be ready to do their own research. The most important task is to ensure your cannabinoid products have been tested for toxins by a ISO-17025 certified lab. Most product contamination is accidental and often arises in the cannabis growing or manufacturing processes. A reputable lab will prepare Certificates of Analysis (COA) showing if the product Passed or Failed various heavy metal, mold, bacteria, and solvent tests.
For topical and transdermal products that are intended to be applied directly to the skin, local irritation may be a concern for some individuals. Patients should be instructed to avoid products containing known allergens and discontinue use if irritation occurs.
There are thousands of cannabinoid product manufacturers in the U.S., so it is also recommended to choose brands that grow and extract their own cannabis, or have some quality controls in place ensuring the product you buy (and like!) today will be available in subsequent batches.
Trying different products from various manufacturers is worthwhile. Each person has a unique body type and will respond differently to each cannabinoid profile and delivery method.
 Casiraghi A, Musazzi UM, Centin G, Franzè S, Minghetti P. Topical administration of cannabidiol: Influence of vehicle-related aspects on skin permeation process. Pharmaceuticals (Basel). 2020;13(11):337. Published 2020 Oct 23. doi:10.3390/ph13110337
 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
 Peyravian N, Deo S, Daunert S, Jimenez JJ. The anti-inflammatory effects of cannabidiol (CBD) on acne. J Inflamm Res. 2022;15:2795-2801. Published 2022 May 3. doi:10.2147/JIR.S355489
 Palmieri B, Laurino C, Vadalà M. A therapeutic effect of cbd-enriched ointment in inflammatory skin diseases and cutaneous scars. Clin Ter. 2019;170(2):e93-e99. doi:10.7417/CT.2019.2116
 Patel PM, Lio PA. Safety and Sourcing of Topical Cannabinoids: Many Questions, Few Answers. J Clin Aesthet Dermatol. 2021;14(8):49-51.