We have treated 10 patients suffering from kala-azar in Brazil with Amphocil (amphotericin B cholesterol dispersion) at a dose of 2 mg/kg/d for 5 d, following an earlier study in which this dosage for 7 d was found to cure all of 9 patients, with no relapse during 12 months. In the present study, all patients demonstrated initial resolution of disease. Parasites were absent upon bone marrow re-aspiration 2 weeks after therapy; no spleen extended beyond the costal margin 2 months after therapy; white blood cell counts, platelet counts, and serum levels of albumin rapidly returned to normal. Although one patient relapsed at 5 months, 8 of the other 9 patients had spleens of normal size (undetectable on deep palpation) at 12 months after therapy. Fever, sometimes accompanied by increased respiratory rate, occurred on the first day of drug infusion in 8 of 10 patients and was more severe in patients < 6 years old. Pre-medication with a non-steroidal anti-inflammatory agent (diclofenac potassium) before the next 4 infusions protected against this side effect in 5 of 6 patients. The results of this and our previous study suggest that the most appropriate regimen of Amphocil for kala-azar is 2 mg/kg/d for 7 d, with pre-medication each day, in patients aged > 5 years.