Vaginal retention of 2% butoconazole nitrate cream: comparison of a standard and a sustained-release preparation.

The purpose of this study was to establish the length of time that butoconazole nitrate 2% standard cream and sustained-release cream could be detected in the vagina after a single administration of 5 g of cream that contained 100 mg of butoconazole. Sixteen healthy subjects received a single vaginal dose of either the standard (8 patients) or the sustained-release preparation (8 patients). Participants returned daily for vaginal examination and collection of specimens to determine the presence of the drug. The specimens were analyzed for butoconazole content using high-performance liquid chromatography. All subjects in both groups had detectable levels of butoconazole present in the vagina for the first 2 days of the study. The sustained-release cream was demonstrated to be present in the vagina in 7 subjects on the third day, 5 on the fourth day, and 1 on the seventh day, while only 1 subject who received standard cream retained it on the third day and none did so thereafter. Analysis of these data demonstrated a median vaginal retention time of 2.57 days with the standard cream and 4.20 days for the sustained-release preparation (P = 0.0024).