Topical vitamin A acid in the treatment of acne vulgaris (a controlled multicenter trial).

A controlled non-blind multicenter trial was conducted in 211 acne patients to test the activity of topical retinoic acid against sulfur-resorcinol--salicylic acid and placebo. Uniform evaluation criteria were used. After 8 weeks' treatment in comparable groups of patients, retinoic acid proved to be superior to the standard and to the placebo. The difference was statistically significant. Side effects were present in a number of patients treated with the active substances and with the placebo (mainly erythema), but rarely was the treatment discontinued.