Three different therapeutic schedules for paracoccidioidomycosis were studied. Twenty three thoroughly investigated patients were submitted to long terrn treatment courses using either sulfadoxine, or sulfamethoxazol + thrimethoprim (SMZ + TMP) or Anfotericin B. Clinicai, roentgenographic, mycological and serologic evaluations were extensively performed. Particular attention to possible hematopoietic abnormalities due to long term, low-losage SMZ + TMP therapy was given. Data presented suggest that there seems to be no advantage in using SMZ + TMP in previously untreated patients, as compared to sulphadoxine alone. Otherwise sulpha-resistant patients may be successfully treated with the association SMZ + TMP. No side effects of clinicai significance were observed. Emphasis in given to good tolerance observed in patients submitted to as much as two years low-dosage therapeutic courses with the association SMZ + TMP.