High-concentration L-menthol exhibits counter-irritancy to neurogenic inflammation, thermal and mechanical hyperalgesia caused by TRPA1-agonist trans-cinnamaldehyde

The TRPM8-agonist L-menthol has been used traditionally for its topical counter-irritant properties. While the use of topical L-menthol for pain is casuistically established, evidence regarding its efficacy is negligible. This study aimed to characterize the effect of L-menthol as a counter-irritant on cutaneous pain and hyperalgesia provoked by topical application of the TRPA1-agonist trans-cinnamaldehyde (CA). In a randomized, double-blinded study CA was applied to a 3x3cm area of the volar forearm evoking neurogenic inflammation, pain, mechanical and thermal hyperalgesia in 14 healthy volunteers.

from The Journal of Pain http://ift.tt/1ZbsjIO
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