Biliary excretion of a new semisynthetic cephalosporin, cephacetrile.

The biliary excretion of a new derivative of cephalosporin, cephacetrile (CIBA 36 278 Ba), was studied (i) in the isolated perfused rabbit liver, (ii) in humans with a duodenal tube, and (iii) in patients after cholecystectomy with a Kehr's drain in the common bile duct. The biliary excretion of the antibiotic was very low in the perfused liver, and no antibiotic activity was found in liver tissue at the end of the experiment. This observation, together with the finding of a rapid decline of the antibiotic concentration in the circulating blood serum, favors the assumption that a metabolic transformation of CIBA 36 278 Ba in liver tissue takes place. In humans, the antibiotic concentration was found to be low both in the duodenal juice and in the bile obtained by external drainage. The biliary concentrations found in these subjects seem to be inferior to those required for the inhibition of the common bacteria of biliary infections. In renal failure, however, the biliary excretion of CIBA 36 278 Ba increased considerably.