[Fundamental and clinical studies on tazobactam/piperacillin in the pediatric field].

Pharmacokinetics, efficacy and safety of tazobactam/piperacillin (TAZ/PIPC), a new beta-lactamase inhibitor combined with a penicillin antibiotic, were studied in pediatrics and the following results were obtained. 1) Serum concentration and urinary excretion of TAZ/PIPC after intravenous administration at a dose of 46 mg/kg to one child were investigated. Serum half-lives were 0.5 hours for TAZ and 0.6 hours for PIPC, while the urinary recovery rates in the first 6 hours after administration, were 61.6% and 56.3% respectively. 2) TAZ/PIPC was administered at a dose of 46.0-73.5 mg/kg t.i.d. for 3-13 days to 10 patients, 6 with respiratory infection, 1 with pharyngotonsillitis, 1 with pertussis and 2 with soft tissue infection of skin. Clinical response were excellent in 5 cases and good in 5 cases, and the efficacy rate was 100%. Bacteriologically, 2 strains (Staphylococcus aureus and Streptococcus pyogenes) isolated from 2 patients were eradicated after the treatment. As for adverse reaction, mild skin rash was observed in 1 case but disappeared within 2 days after withdrawal of the drug. As for abnormal laboratory test results decrease in neutrophiles and increase in eosinophiles in each 1 case were observed, which were, however, normalized after administration. From the above results, tazobactam/piperacillin was considered to be a useful antibiotic in the pediatric field.