PHARMACEUTICAL COMPOSITIONS FOR LOCAL USE CONTAINING A LOW CONCENTRATION OF BENZOYL PEROXIDE IN SUSPENSION IN WATER AND MIXED WITH WATER ORGANIC SOLVENT

摘要

1. A water-based composition for topical application to the skin, comprising: water, a water-miscible organic solvent and benzoyl peroxide,! in which the concentration of the organic solvent is sufficient to provide a stable suspension of benzoyl peroxide in the specified composition on a water basis without inclusion in the composition of the surfactant,! moreover, the ratio of the concentrations of water and organic solvent in the composition is sufficient to maintain benzoyl peroxide in the state of maximum solubility in the composition after application to the skin, and! the concentration of benzoyl peroxide is less than 5.0 wt.%, but at least 1.0 wt.%. ! 2. The water-based composition according to claim 1, characterized in that the concentration of benzoyl peroxide is from 2.0 to 3.5 wt.%. ! 3. The water-based composition according to claim 2, characterized in that the concentration of benzoyl peroxide is about 2.5 wt.%. ! 4. The water-based composition according to claim 1, characterized in that said organic solvent is a polyol, preferably propylene glycol. ! 5. The water-based composition according to claim 1, characterized in that the concentration of the organic solvent is lower than the concentration at which the entire benzoyl peroxide in the composition dissolves after all water is removed from the composition. ! 6. The water-based composition according to claim 1, characterized in that the concentration of the organic solvent is 1-4 times higher than the concentration of benzoyl peroxide in the composition. ! 7. The water-based composition according to claim 1, characterized in that the mass ratio of water to organic solvent in the composition is at least 7: 1, preferably at least 10: 1, most preferred