Stability of ondansetron hydrochloride in injectable solutions at -20, 5, and 25 degrees C

The stability of ondansetron hydrochloride in 5% dextrose injection and in 0.9% sodium chloride injection when stored frozen, refrigerated, and at room temperature was studied. Solutions of ondansetron 0.03 and 0.3 mg/mL (as the hydrochloride salt) were prepared by adding 1.5 or 15 mg of the drug to 50-mL minibags containing 5% dextrose injection or 0.9% sodium chloride injection. All solutions were prepared in triplicate, and each container was tested in duplicate. Testing at the time of preparation and at each subsequent test interval included visual inspection of color and clarity, determination of pH, and a stability-indicating high-performance liquid chromatographic assay to measure the ondansetron concentration. Conditions assessed included storage at -20 degrees C for two weeks to three months, 5 degrees C for 7-14 days, approximately 25 degrees C for up to 48 hours, and various combinations of these conditions. The concentration of ondansetron in each solution remained above 90% of the original concentration at each observation time under all storage conditions. No changes in color or clarity were observed, and there were only minor changes in pH. Ondansetron 0.03 and 0.3 mg/mL in 5% dextrose injection or 0.9% sodium chloride injection was stable when stored (1) for up to three months at -20 degrees C, followed by up to 14 days at 5 degrees C and by 48 hours at 25 degrees C and (2) for up to 14 days at 5 degrees C, followed by up to 48 hours at 25 degrees C.