The science on cannabis topicals for headachesColleen Fisher TullyOctober 31, 2019
If peppermint oil rubbed onto the forehead, neck or temples can provide headache relief, couldn’t a cannabis topical go the extra mile and dissolve the pain altogether?
For now, the health community says no, mainly because we’re missing human clinical trials to say whether cannabis applied to the skin is effective at all for headaches and migraines. But that’s not to say anecdotal data has been a dead end—in fact, just the opposite. A 2017 report amassed a large body of preliminary studies, concluding that we have enough evidence to start clinical trials on cannabis headache treatments. The report even made it a point to say that “cannabis is commonly used to self-medicate for headache disorders”.
Dr. Stefan Kuprowsky, a Vancouver-based naturopathic doctor specializing in ethnomedicine and ethnopharmacology, agrees the theory of topical cannabis relief for headaches is sound, especially given cannabis’s known anti-inflammatory benefits.
“Right now, topicals are most useful for joint-type pain, muscle pain and skin rashes such as eczema, acne and psoriasis,” he says. By extension, a cannabis product could also be helpful for headaches, which are often inflammatory in nature.
Headaches are more than skin-deep
Not all headaches are created equal.
But before slapping CBD oil onto your forehead, know that there’s a catch: cannabinoids are not so easily absorbed into the bloodstream through skin, and most headaches are caused by blood vessels in the brain running amok. While there are promising pre-clinical trials for transdermal patches which breach the bloodstream, it’s not known whether they can treat headache pain.
As for topical creams or ointments, Kuprowsky offers a note of caution: “It’s not the same mechanism, like for osteoarthritis, where a topical would be useful right in the areas where it hurts. Headaches are a little bit more complicated, so just putting it on where it hurts doesn’t necessarily get at the underlying problem.”
However, not all headaches are created equal. For example, tension headaches often start at the base of the skull where neck muscles tighten, sending up an inflammatory response. Kuprowsky says a cannabis topical could theoretically be helpful for the muscle tissue, which could in turn reduce headache pain.
Kuprowsky adds that a range of migraine symptoms—including pain, nausea, and sensitivity to light and sound—could be mitigated by CBD, which he says may potentially act like triptans, a commonly prescribed migraine drug. Pre-clinical studies are promising, but we need clinical trials to confirm.
Nothing works in isolation
Cannabis has a well-documented entourage effect, meaning the cannabinoids in the plant work synergistically with each other, and with the plant’s terpenes, flavonoids, and other botanical components. Cannabis can boost active compounds in other ingredients, too, as when mixed into an ointment or cream.
Kuprowsky suggests that a cannabis ingredient might enhance other medicinal ingredients present, so you wouldn’t feel the cannabinoids per se, but could theoretically benefit from their ability to strengthen everything else. “If you combine CBD [with other ingredients], then you may have a synergistic effect. And if the CBD isn’t helping on its own, it’s complementing the other herbs.”
But he does warn against placebo effect, which he says people in pain are very susceptible to. “Placebo effect is actually a very effective treatment for pain,” he explains. So when it comes to CBD, he cautions that the hype may be responsible for some of the enthusiastic feedback regarding its ability to mitigate pain.
For now, we wait for science to confirm whether topicals are useful for aching heads, or better served as salves for muscles and joints.