Biliary excretion of moxalactam

The biliary excretion of moxalactam was studied in 11 postsurgery patients who had indwelling T-tubes inserted in their common bile ducts. Peak levels of moxalactam in the bile reached mean levels of 33.7 ± 11.1 and 173.7 ± 67.0 μg/ml 2 h after intravenous administration of a single 500- or 2,000-mg dose, respectively. In 5 of the 10 patients given the 2,000-mg dose, peak moxalactam concentrations in the bile were 2 to 12 times higher than simultaneous serum levels, but considerable variation in the biliary excretion of maxalactam was observed among the individual patients.