The efficacy of fluconazole in the treatment of systemic fungal infections was evaluated in an open non-comparative trial. A total of 48 patients with proven or suspected fungal infections were enrolled in 40 of whom efficacy was evaluable. Candida albicans accounted for 90% of the infections. Candida parapsilosis, Candida glabrata, Histoplasma capsulatum and Aspergillus fumigatus caused the infection in one case each. Fluconazole was administered at a dosage of 200-400 mg daily for a mean duration of 15 days. Fluconazole treatment was successful in 53% of the patients. In patients with proven or probable Candida albicans infections a clinical and mycological response was achieved in 62% and 65%, respectively. In 11 patients elevation of liver enzymes was considered to be possibly related to fluconazole treatment; modification of treatment was not necessary in any case. Fluconazole was found to be a well tolerated and effective agent for the treatment of systemic Candida albicans infections.