Ruby laser-assisted hair removal: a preliminary report of the correlation between efficacy of treatment and melanin content of hair and the growth phases of hair at a specific site.

An unpredictable response, even in patients with dark hair, often undermines successful ruby laser hair removal. A prospective clinical study was carried out to evaluate the roles of melanin content and growth phases of hair in treatment efficacy. Thirty-six volunteers with white skin and dark hair were recruited for the study, and were all treated using the Chromos 694 Depilation Ruby Laser. The overall efficacy of treatment was assessed at the end of 3 months. The efficacy of laser treatment is not due solely to the proportion of hair in the growing or static phase of the hair cycle. There is a lack of correlation between the melanin content and the overall efficacy of laser hair removal in those treated once, but patients with darker hair responded better after repeated treatments. The proportion of hair in the growth phase and the melanin content of hair do not contribute solely to the efficacy of ruby laser hair removal.