[Piperacillin: pharmacokinetic studies on the biliary and renal excretion (author's transl)].

9 patients (6 female, 3 male) with either cholelithiasis or choledocholithiasis submitted to cholecystectomy were studied during the postoperative period. Sodium 6-[D-(--)-alpha-(4-ethyl-2,3-dioxo-1-piperazinylcarbonylamino)-alpha-phenyl-ace tamido]penicillinate (piperacillin) was administered in single i.v. doses of 2 and 4 g on the 4th and 6th postoperative days. Serum samples were taken at intervals of 20 min over a period of 3 h post injection and bile was collected via T-tube drainage in 20-min periods also for 180 min. The total urine outputs were collected for the periods 0--6 h, 6--12 h and 12--24 h after administration of the drug. The maximum concentration of piperacillin in the bile was observed 60--120 min post administration. The values in the bile were found to exceed the corresponding serum concentrations 30--40fold. Within 3 h 9.6 (+/- 6.5)% and 13.4 (+/- 5.0)% were eliminated in the bile after 2 and 4 g injections, respectively. The percentage of the administered drug excreted in the urine within 24 h was 56.3% (2 g i.v.) and 66.0% (4 g i.v.).