By LIM KELVIN
Principal Trainer, CARiNG Pharmacy
Essential oils (windy oils) or muscle rubs are widely used across Asia to alleviate various forms of discomfort. We apply these methyl salicylate-containing products to our heads for dizziness, to our joints and muscles when they’re sore, and even to our stomachs to “dispel the wind”. Many people in Asia agree that these oils or rubs have seemingly magical properties that remedy minor ailments.
However, there’s a lack of consensus on what using methyl salicylate feels like. Some say it feels HOT (like cabai), while others say it’s COLD (like ice).
Why are the responses so polarized? Who’s correct?
Interestingly, both groups are.
Methyl salicylate acts on two specific ion channels, TRPV1 and TRPM8. These channels, part of the Transient Receptor Potential (TRP) family, are like tiny gates in our cells’ walls, particularly in sensory cells. They open when they detect stimuli like heat, cold, pressure, or certain chemicals found in spicy food or minty gum.
TRPV1 is triggered by heat and capsaicin (the compound that makes chili peppers hot), whereas TRPM8 responds to cold temperatures and menthol. Hence, when our skin comes in contact with methyl salicylate, we feel BOTH hot and cold sensations.
Yet, there’s another intriguing aspect regarding these topical applications
Why does applying a product containing methyl salicylate feel so much more intense after a bath or when sweating?
The answer lies in our skin’s permeability, which increases after being soaked in water or sweat. Keratin, a protein in our skin’s outer layer, can absorb water and swell. This alters the structure of the stratum corneum, our skin’s outermost layer, making it more susceptible to penetration by topically applied substances like steroidal creams and methyl salicylate.
This increased permeability and the abundance of water allows methyl salicylate to stimulate the TRP channels more quickly and intensely, often resulting in an overwhelming sensation.
If you’ve ever applied something with methyl salicylate on the back of your neck while sweating, here’s a tip: Don’t just wipe it away with a towel. Soap can remove the lipophilic methyl salicylate more effectively. So, simply lather up and rinse. You’ll feel relief much more quickly.