Isoconazole is structurally related to miconazole and econazole and was synthesized by Janssen Pharmaceutica. The compound has been marketed in several countries, but not in the United States. It has broad-spectrum activity in vitro against dermatophytes, pathogenic yeasts, pathogenic filamentous fungi, gram-positive bacteria, and trichomonads . The mode of action appears to include rapid reduction in ATP concentrations caused by damage to the fungal cell membrane. Isoconazole interacted with the cell wall and caused convolutions and wrinkles. Isoconazole also inhibited the enzyme-catalyzed release of spheroplasts from young yeast cells. A recent study has demonstrated that application of the free base of isoconazole in combination with a volatile/nonvolatile vehicle, e.g., ethanol/propylene glycol, can increase drug bioavailability in the skin. This observation may lead to newer formulations of isoconazole and broaden its use for topical (e.g., spray) treatment of yeast and dermatophytic infections. Dermatophytic Isoconazole has been developed and marketed primarily as a once-a-day, topical anti-Candida agent for the treatment of vaginal candidiasis. Studies evaluating isoconazole have demonstrated that 80 to 90% of patients with vaginal candidiasis who were treated once a day with the drug remained clinically and mycologically cured. Following insertion of two 300-mg tablets, concentrations of isoconazole in the vagina remained above minimum inhibitory and minimum fungicidal levels for at least 72 h. Isoconazole has been developed and marketed primarily as a once-a-day, topical anti-Candida agent for the treatment of vaginal candidiasis. In clinical studies, very little of the drug entered the blood after a single vaginal application of a 600-mg dose; the same dose did not adversely affect intestinal flora by inducing a proliferation of yeast like species following prolonged administration. Studies evaluating demonstrated that 80 90% of patients.

Miconazole is a synthetic imidazole derivative, a topical antifungal agent for use in the local treatment of vaginal, and skin and nail infections due to yeasts and dermatophytes. It is particularly active against Candida spp., Trichophyton spp., Epidermophyton spp., Microsporum spp. and Pityrosporon orbiculare (Malassezia furfur), but also possesses some activity against Gram-positive bacteria. It binds to the heme moiety of the fungal cytochrome P-450 dependent enzyme lanosterol 14-alpha-demethlyase. Inhibits 14-alpha-demethlyase, blocks formation of ergosterol and leads to the buildup of toxic methylated 14-a-sterols. Miconazole also affects the synthesis of triglycerides and fatty acids and inhibits oxidative and peroxidative enzymes, increasing the amount of active oxygen species within the cell.