Acute Acne Flare following Isotretinoin Administration: Potential Protective Role of Low Starting Dose

Acne flare-up during the first month of treatment with oral isotretinoin is a recognized phenomenon. To avoid a flare, starting treatment with a daily dose of no more than 0.5 mg/kg is recommended. The purpose of this observational study was to assess if starting daily doses lower than 0.5 mg/kg can further reduce the occurrence of flares during the first month of isotretinoin administration. One hundred thirty-two acne patients receiving an initial daily dose ≤ 0.2 mg/kg were retrospectively compared with 142 patients treated with a starting dose of 0.5 mg/kg/day. In both groups, the dosage was progressively increased until the highest tolerated dose ≤ 1 mg/kg. A significantly lower incidence (p=0.0415) of flare during the first 4 weeks of treatment was found in patients who started isotretinoin at a daily dose ≤ 0.2 mg/kg compared with patients receiving 0.5 mg/kg. Based on these findings, initial doses of less than 0.5 mg/kg/day may potentially reduce acute acne flare occurrence and its related distress.