Can THC Be Absorbed through the Skin?

Tetrahydrocannabinol, or THC, is the primary psychoactive compound found in the cannabis plant. The characteristic high often associated with the cannabis plant is courtesy of this compound. The standard methods of cannabis consumption include smoking or ingestion, which implies THC is often smoked or ingested. However, in recent years, the interest in topical use of cannabis has reached an all-time high. In this brief, we are going to try and answer the question that is being asked by many in the cannabis community: Can THC be absorbed through the skin?

How Well Do You Know Your Skin?

Before we get all technical about cannabis' interaction with skin, let us try to understand the structure and barrier function of human skin, which has three primary layers: epidermis, dermis, and hypodermis. When we say skin is the protective barrier of the human body, it is the epidermis we mainly discuss. 

• The epidermis, the outermost layer, comprises multiple layers of cells—which can prevent most substances from penetrating the human skin. 
• The dermis contains blood vessels and nerves. 
• The hypodermis, the deepest layer, is mainly composed of fatty tissue. 

Having comprehended the basic structure and barrier function of skin, we are now in a better position to understand the answer to the question of THC absorption through the skin.  

So, Can THC be absorbed through the Skin?

The short answer to this question is yes. 

However, based on researchers' findings, there’s also a long answer. Research has found that THC can permeate the skin at a transdermal level. However, the permeability of the skin results in fairly low absorption. There are two reasons for this low transdermal absorption: the large size of THC molecules and the lipophilic nature of the molecules.

It may be disappointing to discover that THC’s absorption doesn’t live up to its fullest potential. However, researchers have some good news. It is possible to increase the human skin's permeability by influencing factors such as the concentration of THC in the topical product, your formulation (the type of cream or gel), and the application area. Researchers have found that these factors must be considered when opting for topical application of THC. Only then can the compound reach systemic circulation levels significant enough to induce intoxication. 

Similarly, another study found that if permeation enhancers were cared for, THC absorption through the skin could improve significantly. Permeation enhancers can temporarily disrupt the human skin's barrier function, allowing for better THC penetration. However, certain concerns regarding the safety of these permeation enhancers have been expressed, and understandably so. Tinkering with the human skin's natural function for too long is not advisable, and using these enhancers requires further investigation. 

Applications of Topical THC

While the transdermal permeability of THC is certainly not at the efficient levels one would hope for, the topical applications of THC have shown certain promise in specific conditions. Cannabis creams and ointments have great potential when a localized effect is needed. 

When combined with other cannabinoids and terpenes, the local effect of THC is bolstered to a great extent. Full spectrum cannabis products, particularly, have a significant value when applied topically. THC molecules can interact with the cannabinoid receptors in the human skin's endocannabinoid system. Hence, they can prove effective for local applications.

Precautions

Can you absorb THC through your skin? As mentioned earlier, one must be extremely careful when using THC topical products, primarily because of safety considerations. The psychoactive effects of THC are quite minimal in the cases of topical application, as compared to other routes. However, one can still experience some local reactions, including redness, irritation and allergic responses. Hence, opting for a patch test in a small area of skin before you apply THC-based topicals directly is a great idea. Also, please pay special attention to the source and quality of your THC products. It is best to get your THC-infused topicals from reputable and licensed dispensaries to guarantee accurate labelling and product quality. Also, please don't use THC topicals and ointments on open wounds or damaged skin. This can increase the risk of adverse reactions tremendously.  

Final Thoughts

Here is a summary of what we have learned in this brief!

• Can THC be absorbed through skin? Yes!
• Can THC absorb through skin? Yes, but the compound’s transdermal permeability is relatively low.
• The skin's protective barrier limits THC's systemic absorption, rendering topical application less likely to cause intoxication.
• Topical THC products have shown promise due to their interactions with the endocannabinoid system in the skin.
• Before using THC topicals, it is crucial to consider safety precautions, potential side effects, and product quality.