Benzoyl peroxide reactions in an acne study group

Benzoyl peroxide patch testing was performed on 60 young adults who had participated in a double-blind acne study. 25% of those who had used a benzoyl peroxide product showed reactivity of +1 or greater (on a 0--3 scale). None of these individuals demonstrated symptoms suggestive of irritancy or allergy greater than those who did not have positive patch tests and who were on the same treatment program. The positive patch tests did not correlate with acne treatment responses. 2 of 44 individuals in the acne study group developed clinical allergy and had dramatically positive patch tests, while the majority of individuals with positive patch tests could use products containing benzoyl peroxide daily without significant adverse effects.