[The biliary excretion of azlocillin]

The excretion of azlocillin into the human biliary tract was investigated in 8 patients with a T-tube in the common bile duct after intravenous injection of 2 g. Samples of serum and common duct bile were assayed from 15 min to 12 hours after injection. Biliary tract levels generally run parallel to serum levels but were about 15 times higher than those. Peak levels in T-tube bile averaged 1137 mg/l 60 to 90 min after administration. 12 hours after administration there were still mean concentrations of 13 mg/l to be found. It is concluded that azlocillin concentrations in bile exceed for a long time the minimum inhibitory concentrations for gram-negative and gram-positive causative organisms (above all E. coli, enterococci, Klebsiella spp., Proteus spp., staphylococci) of biliary tract-infections.