Menthol
Cooling counter-irritant that activates TRPM8. Triggers flushing in active rosacea and stings on compromised barriers.
What it does
Menthol activates the TRPM8 cold-sensing receptor, producing the cool sensation marketers describe as "tingling" or "refreshing." In rosacea-active skin, the neurogenic loop that menthol opens overlaps with the same flush pathway capsaicin activates from the warm side — both are TRP-channel triggers and both are documented to provoke or worsen episodes. On a compromised barrier, the cool sensation is often accompanied by stinging or sharp burning. Stick with fragrance-free formulas while flaring.
The evidence, graded
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
l-menthol, levomenthol