Clinical trial of bleaching treatment with 10% all-trans retinol gel
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Kotaro Yoshimura1, Akira Momosawa, Emiko Aiba
1Department of Plastic and Reconstructive Surgery, University of Tokyo, Graduate School of Medicine, Tokyo, Japan. yoshimura-pla@h.u-tokyo.ac.jp
Background:
Although an aggressive use of tretinoin along with hydroquinone enables an efficient treatment of hyperpigmented skin lesions, irritant dermatitis remains to be solved.
Objective:
To evaluate the efficiency and adverse effects of 10% all-trans retinol (ROL) gel for improvement of skin hyperpigmentation.
Methods:
Ten-percent ROL gel was used instead of 0.1% tretinoin gel in our two-phased bleaching protocol (bleaching and healing phases); 5% hydroquinone and 7% lactic acid ointment were used along with ROL gel in the bleaching phase (2 to 6 weeks). Five-percent hydroquinone and 7% ascorbic acid ointment were used alone during the healing phase (4 to 6 weeks). Twenty-one Japanese patients with hyperpigmented lesions on the face were enrolled in this study, and 18 patients who were followed for more than 10 weeks were analyzed.
Results:
Improvement of pigmentation was seen in 16 of 18 patients after an average treatment period of 11.3 weeks, and in 6 patients, pigmentation was almost eliminated after treatment. Erythema and scaling were seen, however, during the bleaching phase as well as the bleaching treatment with tretinoin gel.
Conclusion:
ROL can improve skin hyperpigmentation to a similar extent to tretinoin when used at high concentration, whereas it induces irritant dermatitis as well.
