The treatment of two patients with severe mucosal leishmaniasis due to Leishmania braziliensis braziliensis is described. Both patients had received much prior antimonial therapy and one had relapsed after a total dose of 2.5 g of Amphotericin B. Both patients responded to prolonged continuous Pentostam therapy at a daily dose of 20 mg Sb(v)/kg/day for 62 days in one case and for 85 days in the other. Pentavalent antimonials can be curative in such protracted courses in selected patients unresponsive to standard chemotherapy.