Let’s talk about itch for a minute. Itch is very common. Everyone, you included, will experience itch at some point in life. Itch can be caused by so many different things—a skin problem, like a rash, an underlying medical condition, like diabetes, a medication, like percocet, a neurologic disorder, like itch after shingles, or for reasons that we simply don’t understand. This last kind of itch is called idiopathic, or primary, which literally means we don’t know why it’s happening, and it’s really challenging for a dermatologist like myself to treat because oftentimes it can be the most difficult type of itch to get controlled.
Let’s talk about a study. In 2016, there was a study that involved 50 people who suffered from chronic itch. Chronic itch simply means itch that lasts for more than 6 weeks. So, this group of 50 people with itch lasting more than 6 weeks, had idiopathic itch, but also itch related to diabetes, liver disease, and kidney disease. These are very common causes of itch. People who had itch from an underlying skin condition like eczema or psoriasis were not allowed to participate. Half of the people in this study were provided with petroleum jelly (also known as vaseline) and the other half was provided with peppermint oil. The concentration of peppermint oil was 5% and it was mixed in a petrolatum base. Both groups looked the same in terms of gender, degree of itch severity, and all other measures including underlying medical conditions. Both groups were told to put their assigned treatment on their itchy skin twice every day for 2 weeks. Measurements of itch were recorded at the start of the study before anyone started using any treatments, and at the end of the 2 weeks after they finished using their assigned treatments.
And, this is where it gets interesting. In the group of people who were using peppermint oil on their skin for 2 weeks, their itch severity scores were lower by about 50%. In contrast, the group of people who used vaseline without peppermint oil—this was the ‘control’ group—their itch scores didn’t change at all. Because the two groups of people looked identical and the only difference between treatments was 5% peppermint oil, the scientists who performed the study attributed the improvement of itch to peppermint oil intervention—and rightfully so. This is called a randomized, controlled study. It wasn’t blinded, so it’s possible that there was some bias introduced by the scientists who performed it, but overall, this is a reasonably done, high quality study. The only other issue with it is the overall size—50 people is not a huge number of people, so these results may not be generalizable (or apply) to everyone on the planet. In addition, peppermint oil was safe—there were no safety concerns that came up during the study.
So, how does peppermint oil work to relieve itch? There are other studies that show that peppermint oil can interact with nerves—specifically, A-delta fibers and kappa opioid receptors—and can turn off the sensation of itch. I’m not quite sure how to interpret this because historically, dermatologists have understood itch to be a problem with C nerve fibers, which are the same nerve fibers that transmit the sensation of pain. This is why itch and pain are both super debilitating to people who suffer from either condition. At any rate, I find this data compelling and I know that if I ever have an issue with itch that’s lasting more than 6 weeks, the first thing I’m going to try is peppermint oil.
A word on use—based on this study, I would use peppermint oil at a 5% concentration. That means, you would have to mix peppermint oil with another oil in a 1 to 19 ratio. For example, if you wanted to try this at home, let’s use some real numbers. If you were measuring in teaspoon quantities, you’d have to take 1 teaspoon of peppermint oil and combine it with 19 teaspoons of another “carrier” oil—something like avocado oil for example, which is a liquid at room temperature. You could technically use any oil that’s a liquid at room temperature, but I’d recommend avocado oil because it has limited skin penetration and there’s science that it shows that it helps restore your skin barrier. So, you’d mix 1 teaspoon of peppermint oil to 19 teaspoons of avocado oil, and that would give you a 5% peppermint oil solution. You could probably store this at room temperature in an amber glass jar or bottle for a few months and it would likely be stable. So, that’s one practical way to apply this at home.
Catch you next time.
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