[Cefotaxime concentrations in the blood and kidney]

Serum and renal levels of cefotaxime (CTX) were studied. Biological half-life time values in serum of rat following 100 mg/kg intraperitoneal injection were 27.58 minutes by bioassay and 25.02 minutes by high performance liquid chromatography, and that in kidney was 27.79 minutes by bioassay. CTX attained high levels in kidney of both human and rat. The concentration was higher in the cortex than that in the medulla. The activity could not be detected in the fraction of brush border, mitochondria and lysosome. This finding was thought to be a favorable characteristic in conjunction with the gradual decrease in the kidney tissue parallel to serum level.