Stability of Piperacillin Sodium for Injection in Intravenous Infusions

Piperacillin sodium for injection (1-g potency), a synthetic penicillin preparation, was investigated on its change with time in appearance, pH and residual potency after its addition to some intravenous infusions together with various kinds of injections. A total of 54 admixtures of 34 commercial injections combined frequently with synthetic penicillins were used.There was no visible recognizable change in appearance of any admixture. In one admixture, the pH passed the stable range of components within 6 hours. There were 2 admixtures in which the residual potency decreased below 90% 8 hours after mixing. Besides the 3 admixtures mentioned above, there were some others which were questionable as to their compatibility.