Tetrahydrocannabinol (THC) is the cannabinoid most often associated with the psychoactive effects of cannabis. It has this property because when the compound enters the bloodstream via digestion or the lungs, it binds to the CB1 receptors within the central nervous system. In other words, when you smoke flower or eat an edible, THC activates the CB1 receptors in your brain to give those... "classic" cannabis effects.

But how do cannabis topicals work?

The truth is that your skin is quite absorbent. It protects our body against dust and larger particles, but smaller compounds can still go through the outermost layer. There are many ways that THC and other compounds can enter the skin, which can include hair follicles, pores, or through diffusion (when molecules move from an area of high concentration of molecules to an area of lower concentration). 

So, let's say you put some THC balm on your arm. Once the THC has "breached" the outermost layer of skin, it will bind onto the CB1 receptors located beneath, which, in turn, deliver localized effects. 

THC topicals offer targeted relief without psychoactive effects. Generally, people will apply them to areas on the body that may feel sore from workouts or other reasons. Some of the ways enthusiasts have described the effects include: 

Anecdotal evidence suggests that it takes several minutes for the effects to take in, with results lasting between 1-2 hours. You should keep in that these types of products affect everyone a bit differently, so these results may vary. 

THC topicals generally come in cream or roll-on form. To use a topical THC product, apply it to the area where relief is needed, wait for the effects to set in, and reapply as you see fit. It's that simple. 

Many people choose THC over CBD or vice-versa because one is psychoactive and the other is not. However, in either case, you will not likely experience such effects with a cannabis-infused topical. As stated earlier, the effects of a topical are targeted and will likely not impact mood (unless the soothing sensation makes you happy). 

Whether one is more effective depends on your body's endocannabinoid system. However, you should consider the different binding affinities between THC and CBD. 

As mentioned earlier, the endocannabinoid system has two main types of receptors, CB1 and CB2. Although CB1 receptors exist primarily within the brain, there are CB1 receptors in the skin, along with CB2. 

CBD has very little binding affinity to cannabinoid receptors, while THC's affinity is much stronger. If you are looking for greater activation of these receptors (and thus, potentially, more accurate effects), you should go with THC topicals. 

FDA Disclaimer: The statements made regarding these products have not been evaluated by the Food and Drug Administration. The efficacy of these products has not been confirmed by FDA-approved research. These products are not intended to diagnose, treat, cure, or prevent any disease. All information presented here is not meant as a substitute for or alternative to information from health care practitioners. Please consult your healthcare professional about potential interactions or other possible complications before using any product. The Federal Food, Drug, and Cosmetic Act requires this notice.