Pharmacokinetics of some cephalosporins in normal and nephrectomized rabbits

We made a pharmacokinetic study of the cephalosporins cephazolin, cephaloridine, cefoperazone, and cefuroxime in the rabbit. We computed the pharmacokinetic parameters of a two-compartment open model from the plasma concentration time curves obtained at different increasing doses. Cephazolin, cephaloridine and cefoperazone demonstrated a dose dependent kinetics since the constants of apparent rate of elimination and apparent volume of distribution varied with the doses. In order to evaluate the extra-renal of elimination, we performed pharmacokinetic analysis on the same animals after nephrectomy. While cephazolin, cephaloridine and cefuroxime were eliminated primarily through the kidneys, cefoperazone was largely eliminated by extrarenal pathways.