Antifungal agents used in systemic mycoses. Activity and therapeutic use

The development of the polyene antibiotic, amphotericin B, provided for the first time a drug which was clinically effective in many serious mycotic diseases. Unfortunately, it requires parenteral administration and is often toxic, factors which limit the total cumulative dose which can be given. Efforts to utilise combinations of amphotericin B with other agents were best realised with amphotericin B/flucytosine in cryptococcal meningitis, and to a lesser degree in systemic candidiasis. More recently, the introduction of new imidazoles has extended the range of applications of these drugs to fungal diseases. Two members of this group, miconazole and ketoconazole, are promising agents. Miconazole is a parenterally administered agent for patients acutely ill with candidiasis and other mycotic infections. It may be the drug of choice for Petriellidium boydii infections and it is an attractive alternative to amphotericin B for intrathecal administration to patients with fungal meningitis. Ketoconazole offers much less toxicity, the advantage of oral administration, and the possibility of indefinitely prolonged therapy. However, it does not attain high concentrations in either the urine or cerebrospinal fluid. With the imidazoles, we have entered a new era of antifungal therapy which may produce even better antifungal agents than those currently available.