Clinical efficacy and pharmacokinetics of antimony in cutaneous leishmaniasis patients treated with sodium stibogluconate.

The efficacy and pharmacokinetics of antimony were explored in 12 young male patients with cutaneous leishmaniasis following intramuscular administration of sodium stibogluconate equivalent to 600 mg of antimony (Sb). Patients' cure rate was evaluated up to 6 weeks after treatment. Blood samples were collected at different time periods on the first and last days of a 3-week treatment. Twenty-four-hour urine samples were also collected on both occasions for the estimation of renal clearance (CL(r)). The blood concentrations of the Sb time profile were best described by a 2-compartment model with a first-order absorption rate. The mean absorption half-life was 0.21 ± 0.023 and 0.36 ± 0.18 hours for the first and last doses, respectively. A rapid distribution phase was followed by a slower elimination phase of a half-life of 9.4 ± 1.9 and 9.69 ± 2.3 hours for both days, respectively. An accumulation index of 2.33 was calculated. The fraction of dose excreted in urine was 0.386 ± 0.11 and 0.326 ± 0.05 on both occasions, respectively. The mean CL(r) was 4.88 ± 1.13 and 4.58 ± 1.05 L/h. In the current study, all of the patients were completely healed by week 6 after the end of treatment, as judged by the treating physician. In conclusion, the blood profile of antimony seems to be multicompartmental in nature.