Are incremental doses of amphotericin B required for the treatment of visceral leishmaniasis?

One-hundred-and-twenty visceral leishmaniasis patients, all with demonstrable splenic amastigotes after treatment with sodium stibogluconate and pentamidine, were treated with amphotericin B. The patients were allocated into two equal groups matched by age and sex. Patients in one group received amphotericin B in the traditional incremental dose regimen, i.e. 0.05, 0.10, 0.25, 0.50 and 1.0 mg/kg body weight on days 1, 2, 3, 4, and > 4, respectively. Patients in the other group received amphotericin B at a constant 1 mg/kg bodyweight per day from day 1. Each of the 120 patients received a total dose of 20 mg/kg bodyweight. By the end of treatment the incidence of infusion-related toxicities, such as rigor and fever, and of renal toxicities, such as elevated serum creatinine and low serum potassium, was the same in both groups (P > 0.05). The two treatment regimens were also equally effective; every patient was cured and none relapsed within 6 months' follow-up. It is therefore recommended that amphotericin B be given as the full optimal dose (1 mg/kg) from day 1. There seems no advantage in the incremental regimen; not only does it 'waste' 4 days before the optimal dose is reached but it is more expensive and may encourage the development of drug resistance.