The effect of serial dilution of betamethasone-17-valerate on blanching potential and chemical stability.

Abstract

The effect of serial dilution of betamethasone-17-valerate (Betnovate ointment) in Unguentum Merck was investigated using a single application blanching assay in 10 subjects and high performance liquid chromatography. There was no statistically significant difference between any of the diluted formulations with regard to blanching potential. Chemical stability was maintained following a 1:32 dilution for 2 months and 1:4 dilution for 5 months at least, after storage at room temperature.