Abstract
The antibacterial activity of ceftazidime (CAZ, SN401), a new cephem antibiotic, was examined against clinical isolates using the plate dilution method with inoculum size of 106cells/ml. The MICs of the drug were≤0.4μg/ml for E. coli and K.pneumoniae, ≤0.02μg/ml for P.mirabilis and P.morganii, ≤0.8μg/ml for S.marcescens, and≤6.3μg/ml in 91.3% of P.aeruginosa. Pharmacokinetics of CAZ in 6 healthy adults were investigated. Serum levels following intravenous administration of thedrug at a dose of 1.0gwere 173*u;g/ml at 5 min., 90μg/ml at 30 min., 63μg/ml at l hour, 10μg/ml at 4 houms and 2.4μg/ml at 8 hours, respectively, by bioassay method. The β-phase biological half life of the drug was estimated to be 1.6 hours. Cumulative urinary excretion of the drug was 90.2% within 8 hours.
Twenty one patients with infections were treated with CAZ administered by intravenous drip infusion in two divided dose of 2.0g per day for 7-17 days. Excellent response was obtained in 120f these patients, good in 6, fair in 2 and poor in 1. The efficacy rate was 85.7%. No clinical side effect occurred and in only one patient elevated transaminase was observed. CAZ is considered to be an effective and well tolerated drug for infected patients.
