The present invention is directed to a novel combination of excipients with an active ingredient, such as Benzoyl Peroxide based (BPO) which is subject to degradation. In one embodiment the invention is a topical pharmaceutical or cosmetic cleanser composition comprising benzoyl peroxide present in an amount from about 2.0 to about 20% w/w; water, at least one anionic surfactant which is a alkylpolyglucoside (AG) derivative surfactant; at least one humectant, a thickening agent, and optionally at least one dermatologically acceptable excipient.