Cannabidiol (CBD) is the second most prevalent of the active ingredients of cannabis. While CBD is an essential component of medical marijuana, it is not derived from the marijuana plant. In fact, it is derived from the hemp plant and by itself, does not cause a ‘high’.
CBD is a chemical with high solubility in oils and alcohols. In the human body, water-soluble chemicals are easily transported into the bloodstream, whereas oil and fat-soluble chemicals are not. This is mainly because blood itself is a ‘watery’ solution. So, when someone places drops of CBD oil into their mouths, the oil droplets do not mix with the saliva. Only a small proportion of the dose taken gets absorbed by the mucous membrane into the blood. It is estimated that only 5-10% of the total dose taken orally actually gets absorbed. Moreover, any CBD oil that is swallowed and then absorbed from the intestines directly passes to the liver and gets broken down before entering the general blood circulation. Due to this, the effectiveness of CBD oil is also significantly reduced. To make it easily absorbable when taken by mouth, one might have to prepare the CBD in such a way that it is in water-soluble form.
How does CBD interact with the skin?
The outer layer of the skin is primarily made up of lipids. Just like CBD, lipids are insoluble in water but dissolve in solvents such as alcohols. Lipids mainly include oils, waxes, and fats naturally produced by the body. This also includes compounds such as fatty acids and cholesterol. Due to their harmony with lipids, oily compounds are more easily absorbed by the skin than water. This is why products like baby oil, olive oil, or coconut oil help keep skin healthy. Even though CBD is soluble in oils, the compound is poorly absorbed by the skin. Although, it can pass through the skin pores and can enter the body that way. The CBD that passes through skin pores acts locally on cannabinoid receptors in the skin layer, with no detectable amounts being entered into the bloodstream. Therefore, rubbing oil into the skin could help in localized areas.
However, applying high doses or large quantities of CBD oil to the skin can actually result in CBD entering the blood. Although the most convenient method is to take a water-soluble formulation by mouth, studies show that a systemic effect can potentially be achieved by applying the compound to the skin. The most reliable way to achieve this could be by using across-the-skin patches, rather than applying oils, ointments, or gels. These patches contain a concentrated ‘reservoir’ of CBD that ensures the compound is directed into the skin at a steady rate when it is applied to the surface of the body. It then passes into the blood vessels that run through the skin, transporting it throughout the body. When applied to the skin, the rate and extent of absorption are affected by the thickness of the skin as well as blood flow to the area, which is usually dependent on temperature.
Another study showed that transdermal products deliver CBD in a manner that penetrates through the epidermis (the upper layers of the skin) and into the bloodstream. CBD administered as transdermal gel makes its way into the bloodstream and increases the plasma level of cannabinoids. However, it takes several adjuvants to make a hydroalcoholic gel that is capable of penetrating through the skin. So, transdermal CBD isn’t just a matter of rubbing the cannabinoid into the skin. Although the studies on transdermal cannabinoids are still in their initial stages, this method could serve as a way to bypass the digestive system and deliver CBD directly into the bloodstream. Several patents exist for transdermal applications and companies offer products featuring varying ratios of CBD, CBN, THC, and THCA.
Rubbing CBD oil over a particular area of concern in the body can be effective for that particular problem. For a whole-body effect, it is recommended to take water-soluble products that can be taken by mouth. We hope this article has been helpful to you. Thank you for reading and all the best!