At least 40 patients with AIDS and an initial episode of disseminated histoplasmosis are selected for the study. Patients receive fluconazole for a total of 12 weeks. Patients who are unable to take the drug orally may receive it intravenously until oral administration is possible. Patients are evaluated at weeks 0, 1, 2, 4, 8, and 12. Patients who are doing well without evidence of clinical failure or dose-limiting toxicity are permitted to continue maintenance therapy to prevent relapse at a reduced dose for an additional 12 months; those who relapse on the reduced dose are permitted to receive re-induction with a higher dose.