[Evaluation of the biliary excretion of penicillin G. (author's transl)].

Biliary excretion of penicillin G was studied experimentally by perfusion of isolated rabbit liver. Under these conditions, bile recovery accounted for 5% of the amount of penicillin G added to the perfusing blood (10 mg); peak biliary level averaged 135.3 micrograms/ml. In man after intravenous administration of a 599 mg dose of penicillin G (1 MU) to patients provided with T-tube drainage (n = 10), the maximum biliary concentration averaged 18.0 +/- 8.0 micrograms/ml at 2 hours; biliary recovery of penicillin G accounts for 0.12% of the administered dose. The excretion of penicillin G in the juice collected through duodenal tubing in normal subjects averaged 0.07% of the administered dose (599 mg IV). Per-operative assays showed that the concentration determined at 1 hour after intravenous administration of the drug (599 mg) in the gallbladder bile (45.7 +/- 16.7 micrograms/ml) and common duct bile (93.5 +/- 16.3 micrograms/ml) were definitely higher (4.5--9 times) than the serum levels measured simultaneously. The biliary excretion of penicillin G is compared with the biliary elimination of a certain number of beta-lactam derivatives studied under the same conditions (ampicillin, metampicillin, carbenicillin, cefalothin, cefaloridine, cefacetrile, cefalexin, cefazolin).