CBD Topical Drugs: What Do the Studies Say? – MEDCAN24

Take this as a sign of how flexible and ubiquitous the endocannabinoid systems is. We can ingest medicinal cannabinoids in food or drinks, or we can directly absorb them through our skin.

The latter is more complicated and broader than we give it credit. In the mouth it can be absorbed buccal (between cheek and gum, such as a lozenge), or sublingually (under your tongue, like with a liquid tincture).

It also works in two other ways, including topically via TRP (trip) channels and secondary targets such as PPARs, serotonin and PPAR receptors, which are widely expressed in the cells of the skin and in superficial tissues, and transdermally by entering bloodstream.

The advantages and disadvantages of each type

Traditional topicals – including water-based lotions and creams and oil-based balms and salves – offer a quick onset time, no psychoactivity, and the potential to treat not only aches, pains, and inflammation, but also skin conditions like psoriasis and eczema. They are short-acting and have a low bioavailability.

Transdermal formulations or those “crossing the skin” are also systemic. These products act throughout the body, which may result in mild psychoactivity (if THC was involved). They also take longer to work and have a slower effect. Excipients like ethanol and propylene glycol can help the cannabinoids pass the skin barrier to enter the bloodstream. These products also use special delivery methods like hydrogels, nano-emulsions, adhesive patches and other systems. 

What matters to both patients and doctors is whether transdermal and topical cannabinoids work. Much of the research to date has focused on testing cannabidiol or CBD’s ability to treat various forms of pain through a variety of molecular mechanisms – either locally, as with arthritis, muscle soreness, or inflammatory skin conditions; or systemically, for chronic ailments requiring a more controlled and sustained release.

What are the results of these studies?

Benefits of Clinical Treatment

An article from the May 2024 edition of The International Journal of Molecular Sciences This report evaluates current efforts to use CBD transdermally for the treatment of inflammatory pain. This review examines about a half dozen of such studies and another 10 that look at the use of transdermal delivery systems to treat other conditions including epilepsy, drug addiction, neurodegeneration or skin cancer.

Although the authors from Canada concluded that transdermal CBD delivery “shows promise” as a “potential novel treatment for chronic pain,” they acknowledged that there is no certainty that this method will be able to reach the crucial benchmark of providing “tangible benefits”.

The authors write, “There is still a lot to do.”

Around nine months before, a review written by a group of Thai researchers was published in the Journal. Cannabis and Cannabinoid research . This case focused on transdermal and topical formulations. They identified only eight studies which met their criteria. In the end they found that available data about pain and outcomes were unreliable with high risks of bias. They repeat the familiar refrain: “New clinical studies are urgently required.”

Review of Literature 

MEDCAN24, in its own literature review identified four recent studies not mentioned by the previous reviews. Three of the studies are focused on topical/local formulas, and one is a transdermal. Findings are mixed.

The July 2024 Article Cannabis and Cannabinoid research This study evaluates the ability of a CBD-containing cream to reduce muscle pain after exercising. The University of Kentucky researchers randomly assigned 28 women and men (n=15 each) between the ages of early 20s and late 30s to either perform lower-body exercises and then apply CBD cream to the quadriceps, or apply placebo cream.