A regimen is described for providing early onset of action in the therapeutic treatment of rosacea including topically applying a pharmaceutical composition to the skin of a subject in need of said treatment. The pharmaceutical composition includes about 1% to about 10% benzoyl peroxide as the only active ingredient, and a pharmaceutically acceptable carrier or excipient. The pharmaceutical composition is applied once daily for a period of at least about 2, 4, 8 or 12 weeks. Based on early onset of action, a primary measure of success is at least about 9%, primary measure of success being defined as a 2-grade improvement in IGA of clear or almost clear； and a secondary measure of success is at least about 40%, secondary measure of success being defined as mean inflammatory lesion count percent reduction from baseline, after at least about 2 weeks of treatment.
