Since January 1985 more than 100 patients with deep fungal infections have been treated with itraconazole (200 to 400 mg/day) in Northern Italy. Evaluation of the drug efficacy and tolerance was possible in one patient with sporotrichosis, in 34 with aspergillosis, and in 36 with cryptococcosis (mainly patients positive for human immunodeficiency virus). Response to itraconazole alone was obtained in the case of sporotrichosis and in 24 of 34 patients with different forms of aspergillosis (of the 18 patients with invasive pulmonary aspergillosis, 15 were cured). Patients with cryptococcosis received itraconazole for active infection and/or for prevention of relapse. Active infection was treated successfully with itraconazole alone in 9 of 12 patients and with itraconazole plus flucytosine in 8 of 10 patients. Of the 31 patients who received itraconazole maintenance therapy for up to 27 months, 4 (13%) had relapses; 14 (45%) did not have relapses, and decline of serum antigen was detected in 12 of them; and 13 (42%) were completely cured (serum antigen titer dropped to zero). With the exception of hypokalemia in one patient, itraconazole was well tolerated even in patients who received the drug for several months or years.