AUTHORED BY: GENESTER WILSON-KING, MD FACOG & SARAH RUSSO
Cannabis Topicals: More Than Skin Deep Benefits?
Cannabis topicals are becoming increasingly popular in the industry. Many people like to use the plant by applying it to aches, pains, and skin issues. More consumers are gravitating to external ways to take cannabis medicine and some find great benefit with using them as needed. Topicals can also be applied while taking cannabis internally to combat overall inflammation and treat a condition both locally and systemically.
Cannabis topicals are not a new phenomenon. The use of externally applied cannabis preparations dates back to ancient China. Archaeological evidence also indicates that the Egyptians used cannabis topically. External application allows cannabis to work on the body directly from where it is applied to soothe and protect the skin. [1,2] We will break down specifically what topicals are, the science surrounding this mode of administration, and how they work.
The role of the endocannabinoid system on the skin
The skin is the largest organ in the body, and the endocannabinoid system (ECS) influences all of its aspects. The ECS plays an important role in skin homeostasis. It impacts oil production, hair growth, skin pigment, wound healing, and how the skin protects itself. [1,3,4] CB1 and CB2 receptors and the endocannabinoids anandamide, 2-AG, and FAAH are also found in various types of skin cells. The ECS is essential for keeping the inflammatory processes of the body under control. Overall inflammation in the skin and across the body will decrease when the ECS is functioning optimally. [5,6]
The endocannabinoid system also modulates the growth, proliferation, and death of skin cells.  The most common skin conditions are acne and seborrhea. These situations stem from an overproduction of the skin’s oil by the sebaceous glands. The activation of CB2 receptors in these glands enhances the production of oil. Therefore substances that decrease their local production or antagonize CB2 receptors may successfully treat these conditions. [1,3] Certain skin diseases will improve by decreasing endocannabinoid tone. Others will improve by increasing endocannabinoid tone.
Based on current research, acne, seborrhea, and alopecia areata require decreased endocannabinoid tone. Skin tumors, psoriasis, hirsutism, dry skin, pain, and itching would be improved by increasing endocannabinoid tone. The endocannabinoid system influences pain and itching by stimulating the central nervous system. In skin diseases such as psoriasis and tumors where abnormal skin cells replicate rapidly, the skin’s ECS will inhibit cell growth and cause cell death. Skin tumors have shown an abundance of CB1 and CB2 receptors. [1,3]
The use of cannabinoids on the skin may become increasingly important. The antibacterial action of cannabinoids has been researched in-depth and is worthy of further investigation. CBD, THC, CBG, and some acidic cannabinoids have shown promise against treatment-resistant MRSA, a life-threatening skin infection that is becoming more difficult to treat with traditional methods. [1,3] However, at this time there is no indication that cannabis alone would be a viable treatment for MRSA.
The skin’s layers and absorption
The cannabis plant is complex, and the manners in which it is taken into the body is no exception. Topicals exert their effects by activating cannabinoid receptors in the skin. This then sets up the cascade of events that may lead to pain relief, enhanced healing, and decreased inflammation.
When cannabinoids are taken orally, they are processed by the liver before getting into the bloodstream. However, cannabinoids applied externally are difficult for the skin to absorb. This is because cannabinoids are hydrophobic, meaning that they are not water-soluble. Cannabinoids are fat and alcohol soluble. This makes cannabinoid transport over the water-based layer of the skin challenging. Oils only penetrate the first layer of skin (the epidermis). [8,9]
Transdermals are different from topicals. Both routes have distinct effects and advantages. Trandermals usually come as patches that are applied to the body and left there for hours. Topicals generally act on the epidermal layer of skin only.  Transdermal formulations penetrate through to the dermis and beyond to exert their effects on deeper tissues. Transdermal delivery also bypasses the liver and cannabinoids are absorbed directly into the bloodstream. [11,12]
The ability of a substance to cross cell membranes is known as “permeability”. Permeability is a crucial factor in absorption. The permeability of CBD (cannabidiol) and CBN (cannabinol) was found to be 10 times higher than delta-8-THC in a preclinical study in guinea pigs. Researchers focused on these three cannabinoids as ingredients for combination patch therapy. 
THC (delta-9) has been explored for external use as well. A preclinical study in mice demonstrated that topical THC aided skin healing from allergies. A prospective study of three patients with pyoderma gangrenosum (a rare condition that causes large, painful sores) applied THC and CBD-dominant cannabis externally to their lesions. Two of the three patients had a clinically significant improvement in pain and decreased their use of opioids. According to the authors, “This is the first published human case report of topical cannabinoid therapies achieving analgesia that was clinically significant”. 
People often are curious if someone can “get high” from using cannabis topicals. Generally speaking, externally applied cannabis treatments do not have psychoactive effects, even when THC is involved. It requires much more effort for water-phobic cannabinoids to cross the barriers of the skin to get into the bloodstream. However, feeling a psychoactive effect from topical preparations isn’t entirely impossible. It is highly doubtful. It should be noted that when using topicals with THC, it cannot be guaranteed that you would test negative for a drug test. 
Various uses for topicals
People can take cannabis both internally and topically to act on an area from the inside out. This can be especially helpful when systemic medications do not relieve a particular zone of concern. For example, many arthritic patients take cannabis orally or via inhalation for overall relief of pain and inflammation. If arthritis mostly affects the knees, they can apply a topical to relieve local pain where the systemic medication may not be as effective.
Topicals can be made from Type I (THC-dominant), Type II (a combination of CBD:THC), or Type III (CBD-dominant) cannabis products. Currently, there are many CBD-dominant or combination CBD:THC cannabis topicals on the market. Each case and person is unique. A patient may have to try a few types of cannabis products to find what works for them. This is mainly because there are many different topicals and they contain various chemovars, potency, and ingredients.
Advantages of using topicals:
- No systemic effects, therefore no impairment
- Effective local treatment
- No dose limitations
- Minimal side effects
- May enhance the effects of systemic products in the target area
- Can be applied many times per day
- Easy to try different cannabis varieties
Disadvantages of using topicals:
- Effects are only local
- May require application more than once per day
- May be expensive
- Potential need for experimentation with different options to find what works. This is typical of cannabis medicine and can be seen as an advantage or a disadvantage
How to Select from Different Types of Topicals
Cannabis topicals come in a variety of options. Cannabis is typically extracted into an alcohol or oil base and then made into the topical preparation. Alcohol extractions, sometimes known as liniments, have been used as a “folk remedy” for sore joints and other ailments.  A cannabis-infused oil is the base for many cannabis topicals on the market. There are a wide variety of options available to consumers. Here is a breakdown of some of them and how they work.
- Salves & Ointments are usually a semisolid preparation that has no water. They are thick and greasy. Salves and ointments are composed of oil, paraffin, or petrolatum. Their ability to get into the pores is beneficial for dry or inflammatory skin conditions.
- Pastes are a combination of an ointment and a powder. The powder helps give the skin more space to “breathe”. Pastes are ideal for dry skin conditions or on an abnormal area that is surrounded by normal skin. Their texture enables them to stay in the targeted zone and not spread to other areas.
- Creams are a combination of water and oil in close to equal parts. There is a difference between oil in water or water in oil. Oil in water preparations are non-greasy and spread more easily. Water in oil preparations are thicker and stay on the skin longer. Creams can be good to soothe inflammation and for oily skin types. Creams sometimes have preservatives, so be sure to look on the label.
- Lotions are oil in water preparations made up of alcohol and a moisturizing ingredient. Most lotions evaporate quickly and provide an easy application to large areas of skin. They are ideal for “wet” type skin conditions or for oily skin.
- Oils are mostly composed of oil along with the active botanical ingredients. They have the same advantages as lotion, except they are much thicker and don’t absorb into the skin as quickly. They are ideal for dry skin conditions.
- Gels are a semisolid transparent preparation generally made up of cellulose. Gels become a liquid when they are applied to the skin. They can be drying to the skin because they are an alcohol base with no oil.
- Sprays contain ingredients mixed with aerosols, which are a mixture of liquid or solid particles in a gas. Sprays take less time to administer and are easy to apply on difficult to reach areas. [17,18]
To determine what kind of topical you should use for your skin condition, consider the type of skin lesion versus the preparation. For example, if the skin condition is moist or “draining”, avoid an oily or greasy topical. If the condition is in a hairy area, a lotion or a gel would be ideal. Gels tend to be drying so are probably not optimal for skin conditions that require moisturization.
A Final Note
Hopefully now you have a foundation from which to explore cannabis topicals. Remember that some trial and error may be required to find what kind of cannabis product is ideal for your situation. When looking for cannabis topicals, be sure to follow general guidelines for finding high-quality products. Always ask to see a laboratory report (a Certificate of Analysis) from the company or product producer. If using cannabis or topicals for the first time, start off with a small amount and work your way up. And enjoy the journey.
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- Dallmeier, Lorraine. (2013).Can Cosmetics be absorbed into your Bloodstream? Herb & Hedgerow. Accessed on October 21, 2020.
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Genester Wilson-King, MD FACOG is a Board-Certified Obstetrician and gynecologist with over 25 years of clinical experience providing compassionate and research-driven care to patients. After years of working as a full-service OB/GYN, she founded Victory Rejuvenation Center (VRC), a private holistic and preventive medicine practice that provides life-transforming management modalities and customized medicines to patients. She is the Medical Advisor to Treadwell Farms.
As the Medical Director of VRC, Dr. Wilson-King provides services that help her patients age gracefully and achieve holistic well-being. She focuses on plant-based medicine, integrated health, nutrition, supplements, cannabis education, and hormone balance.
Dr. Wilson-King is Co-Vice President of the Society of Cannabis Clinicians (SCC). The SCC is an educational and scientific society of physicians and other professionals dedicated to the promotion, protection and support of cannabis for medical use. Dr. Wilson-King co-authored the Best Practices Guidelines for Cannabis Use in Pregnancy and Breastfeeding, and Cannabis Use in Women – Special Considerations (in progress). She is also on the Board of the Doctors For Cannabis Regulation (DFCR), the first and only national physicians’ association dedicated to the legalization and regulation of cannabis for adults. Advancing the DFCR’s commitment to addressing the disproportionate criminalization of cannabis use among communities of color and the nation’s poor, she regularly provides expert opinions for legal cases involving cannabis.
Dr. Wilson-King is a nationally recognized advocate, clinician, and educator for cannabis and hormone and wellness therapies. She presents on cannabis use in obstetrics and gynecology, hormone therapy for PMS, various stages of menopause, and for applications in nutrition.
Sarah Russo is a longtime plant enthusiast and globetrotter. She got her degree in environmental studies and social justice, with a focus on plant medicine from the Evergreen State College. She is a freelance writer, consultant, and project manager with over 13 years of experience in the cannabis and herbal medicine space. Her main objectives are fighting for the right to use plants, implementing social justice approaches in the cannabis industry, as well as encouraging sustainable agricultural practices. She is currently based on an island in the Mediterranean. Sarah is a content creator for Treadwell Farms.