Studies on metabolism of tazobactam/piperacillin in some animals

Abstract

The metabolism of tazobactam/piperacillin (TAZ/PIPC) in some animals was studied using in vitro and in vitro examinations. The following results were obtained. 1. After intravenous administration of 14C-TAZ/PIPC or TAZ/14C-PIPC to rats, metabolites were investigated in plasma, urine and bile. M-1 was identified as a metabolite of TAZ having a structure of the β-lactam ring-opening product. In the urine, about 70% of unchanged TAZ, about 17% of M-1, and about 25% of unchanged PIPC were excreted for 24h, and in the bile about 60% of unchanged PIPC was excreted for 24h. 2. Plasma and urinary bioactive metabolites in rats, dogs and monkeys were examined by TLC-bioautography. No bioactive metabolites were detected in any specimens. 3. In vitro, stability of TAZ in mice plasma and tissue homogenate was examined. The metabolite M-1 was produced in plasma, kidney and small intestine homogenates. © 1994, Japanese Society of Chemotherapy. All rights reserved.