Taken together, the current study not only gives a hot new twist to human hair growth control by introducing TRPV1 signaling as a potent, physiologically relevant hair growth-inhibitory force that may be clinically exploited, eg, for the treatment of unwanted hair growth (hirsutism) by the topical application of TRPV1 agonists, and of hair loss (effluvium, alopecia) by administering TRPV1 antagonists.

Following oral ingestion of equipotent dose of 26.6 mg of pure capsaicin, the half life was approximately 24.9 ± 5.0 min 4. Following topical application of 3% solution of capsaicin, the half-life of capsaicin was approximately 24 h
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