Topical retinoic acid for treatment of solar damage

Twenty patients with chronic solar damage of the skin were entered in a double-blind, within-patient trial to compare the effect of 0.05% tretinoin cream with a placebo applied once daily for 12 weeks. Sixteen completed the study. Clinical assessment of the individual signs of solar damage were recorded on separate visual analogue scales. After 12 weeks, there were significant improvements in fine wrinkling around the eyes, crease lines around the mouth and cheeks, wrinkling on the dorsum of the hands and yellow discoloration. Overall, 14 of the tretinoin-treated sides were judged to have improved compared to only two of the placebo-treated sides (P = 0.011). Measurement of skin thickness by pulsed A-scan ultrasound revealed that the sides treated with tretinoin were significantly thicker than the placebo-treated sides (P = 0.019). Skin biopsies taken before and after treatment showed an increase in mean epidermal thickness with tretinoin treatment (P = 0.019). The clinical signs of improvement persisted at the follow-up assessment performed 4 weeks after cessation of therapy.