Stable cephalosporin powder injection

The stable cephalosporin powder for injection is mixture of bacteria-free cefpiramide and cosolvent in the weight ratio of 1 to 0.1-0.5. The cosolvent is sodium carbonate, arginine or sodium hydroxide. Compared with available cefpiramide injection, the cephalosporin powder for injection has the features of ever high stability, less impurity content and longer preservation period.