Pharmacokinetics of dactimicin in rats

Dactimicin is a new pseudo-disaccharidic aminoglycosidic antibiotic produced by Dactylosporangium matsuzakiense. The aim of the present research was to evaluate the pharmacokinetics of dactimicin intramuscularly administered, at the dosage of 20 mg/kg, in male Sprague-Dawley rats with an average b.w. of 200-220 g. Dactimicin levels were assessed by using a microbiological method (agar diffusion) employing Bacillus subtilis ATCC 6633 as test organism. Samples were collected immediately before and 0.25, 0.50, 1, 1.15 and 2 h after drug administration. The mean peak serum level, reached after 15 min, was 33.6 micrograms/ml (range 30.3-40 micrograms/ml); T1/2 beta was 0.42 h; extrapolated AUC was 26.8 mg h/l.