In vitro studies of amphotericin B in combination with the imidazole antifungal compounds clotrimazole and miconazole.

The clinically important polyene antibiotic amphotericin B, in combination with two antifungal imidazole compounds, clotrimazole and miconazole, was studied in vitro. With use of results of cytoplasmic leakage, metabolic heat output, and minimal inhibitory concentration studies, a definite antagonistic response was demonstrated. It is suggested that, if combined antifungal drug therapy is clinically indicated, the drug combination be tested against the isolate by the simple technique of measuring cytoplasmic leakage or by the more elaborate method of flow microcalorimetry.