Histoplasmosis is a serious opportunistic infection in patients with AIDS. Although the clinical response to amphotericin B treatment in the AIDS patients is generally good, administration difficulties and toxicity detract from its usefulness. Oral treatment with ketoconazole overcomes these limitations of amphotericin B, but does not appear to be effective for primary treatment in patients with AIDS. Itraconazole is a triazole compound in which preclinical studies have demonstrated activity against Histoplasmosis capsulatum. Preclinical studies have also shown that itraconazole appears effective in the treatment of histoplasmosis. The frequency of adverse reactions to itraconazole has been low in several studies. Central nervous system (CNS) involvement occurs in up to 20 percent of patients with histoplasmosis, and appears to have a poor response to amphotericin B treatment. Itraconazole has been used successfully in a small number of patients with cryptococcal meningitis, supporting a study of its use in CNS histoplasmosis.