Abstract: OBJECTIVE To analyze the compatible stability of pazufloxacin mesylate sodium chloride injection with proton pump inhibitors. METHODS Appearances and pH changes of the solution containing pazufloxacin mesylate sodium chloride injection and omeprazole, pantoprazole and lansoprazole were observed at room temperature(25℃) for different period. HPLC was adopted to determine the content. Spectrophotometric method was used to determine hemolytic rate. RESULTS The color of pazufolxacin sodium chloride injection changed immediately when mixing with proton pump inhibitors, and gradually formed precipitation. When two drugs were mixed, the pH values of mixtures were changed obviously, and the contents of pazufloxacin mesylate were decreased by 83%, 76% and 83%, respectively. The hemolytic rates of the mixtures were increased with the time increasing. CONCLUSION It is unstable of the solution containing pazufloxacin mesylate sodium with omeprazole sodium, pantoprazole sodium or lansoprazole. Pazufloxacin mesylate sodium chloride injection should not be used with any proton pump inhibitors in the same infusion container, and the infusion tube should be washed before and after using above drugs.