IN-VITRO ANTIMICROBIAL ACTIVITY OF TIOCONAZOLE AND ITS CONCENTRATIONSIN VAGINAL FLUIDS FOLLOWING TOPICAL (VAGISTAT-1 6.5-PERCENT) APPLICATION

In vitro assays demonstrated that clinical yeasts were significantly m ore inhibited by tioconaZole (MIC50, less-than-or-equal-to 0.5 mug/ml) than by fluconazole (MIC50, 8 mug/ml). Tioconazole also exhibited hig h potency against most molds (Alterneria spp. and Acremonium spp.). Al l Candida tropicalis isolates had MICs of 8 mug/ml, four-fold greater than any other Candida spp. Generally Gram-negative bacteria were less susceptible to tioconazole. Moraxella catarrhalis (MIC90, 2 mug/ml) w as the most susceptible Gram-negative species. Staphylococci and enter ococci were the most susceptible to tioconazole Gram-positive species (MIC50s, 1-8 mug/ml). Bacterial species associated with vaginosis. [Ga rdnerella vaginalis (MIC90, 16 mug/ml), Mobiluncus spp. (MIC90, 16 mug /ml) and Prevotella biviadisiens (MIC90, 64 mug/ml)] were inhibited by tioconazole. Isolates of Lactobacillus spp. were most resistant (MIC9 0, greater-than-or-equal-to 256 mug/ml) to tioconazole. Vaginal fluid levels of tioconazole (mean, 91.4 mug/ml) persisted above the MIC90 le vels (1-64 mug/ml) for most fungal and bacterial pathogens for 72 h in 19 evaluable female human subjects receiving 300 mg tioconazole in an intravaginal ointment.