Stability of ondansetron in large-volume parenteral solutions

OBJECTIVE: To determine the stability of ondansetron hydrochloride in large-volume parenteral solutions under four storage and time-period conditions. DESIGN/METHOD: Ondansetron was added to each of the following commercially available solutions to make final concentrations of approximately 24 and 96 micrograms/mL: NaCl 0.9%, D5W, and lactated Ringer's solution. SETTING: University analytical laboratory. MAIN OUTCOME MEASURES: Each solution was studied at both concentrations under the following conditions: (1) 1 day refrigerated, 2 days room temperature; (2) 7 days refrigerated, 2 days room temperature; (3) 14 days refrigerated, 2 days room temperature; and (4) 14 days room temperature. All solutions were exposed to fluorescent light when under room temperature conditions and were studied in triplicate. Ondansetron concentrations of samples were obtained periodically throughout each storage/time condition via a specific, stability-indicating HPLC method. RESULTS: A clinically significant loss of concentration was defined as greater than 10 percent decrease from the initial concentration. In all solutions and at both concentrations studied, the mean ondansetron concentration was greater than or equal to 90 percent under all storage and time conditions. CONCLUSIONS: Ondansetron can be stored and administered in these solutions without loss of potency.