1986 Volume 12 Issue 4 Pages 299-302
Stabilities of injectable solutions of five cephem antibiotics (cefmenoxime, latamoxef, cefoperazone, cefotiam, and cefotaxime) at 5 and 25.0°C after dissolution were investigated. The amounts of tetrazoles produced by the degradation of these drugs were also determined.
These drugs were found to be stable, and the amounts of tetrazoles liberated were only slight at 5°C. On the other hand, differences in the stability among the drugs were apparent at 25.0°C. The residual concentrations of drugs after 24 hours ranged from 98.3%(cefoperazone) to 85.2%(cefotaxime) of the initial concentrations at 25.0°C. Furthermore, more tetrazoles were produced with the decrease in the amounts of unhydrolyzed drugs. Nineteen mg of methylthiotetrazole was found in latamoxef solution (1g/vial) and 56mg of dimethylaminoethylthiotetrazole was found in cefotiam solution (1g/vial) after 24 hours.
