Stability of morphine sulfate in Cormed III (Kalex) intravenous bags

The stability of various concentrations of morphine sulfate solution stored in Cormed III (Kalex) i.v. bags at two temperatures was investigated. Solutions of morphine sulfate 0.5, 15, 30, and 60 mg/mL were prepared under a horizontal-laminar-airflow hood with 0.9% sodium chloride solution and placed into 100-mL Kalex bags. Two bags were prepared for each concentration; one was stored at 5 degrees C and the other at 37 degrees C. Samples were analyzed in triplicate by high-performance liquid chromatography on days 0, 2, 5, 9, and 14. All morphine sulfate solutions were stable for 14 days at 37 degrees C, and the 0.5-, 15-, and 30-mg/mL solutions were stable for 14 days at 5 degrees C. However, the 60-mg/mL solution stored at 5 degrees C was found to contain 57% of the actual initial concentration on day 9 and 51% on day 14; the decrease coincided with the appearance of a white precipitate. Beginning on day 5, all the solutions displayed a light brown color that darkened as the study proceeded. This qualitative change was not associated with any change in morphine concentration. Solutions of morphine sulfate 0.5 to 60 mg/mL stored at 5 or 37 degrees C were stable for 14 days in Kalex bags, except for 60-mg/mL solutions stored at 5 degrees C for nine days or longer.