Stability of an extemporaneous formulation of injectable cholecalciferol

THe stability of an extemporaneous formulation of injectable cholecalciferol 40,000 IU/ml was assessed. A preparation of cholecalciferol 40,000 IU/ml in a solution of propylene glycol with ethanol 10% was prepared. The solution was stored at 4 degrees C in 2-ml sterile glass vials protected from light. Cholecalciferol content was measured initially and periodically for 199 days using a high-pressure liquid chromatography technique. A 7.3% loss of cholecalciferol potency from baseline was observed over the 199-day period. In contrast to currently available preparations, this extemporaneous formulation of injectable cholecalciferol potentially offers a versatile dosage form for therapeutic or prophylactic therapy of vitamin D deficiency. It was easily prepared and retained more than 90% potency of cholecalciferol for at least six months. The addition of this formulation to large-volume parenteral or parenteral nutrition solutions is not recommended, however, because compatibility data are not available. In addition, the biological activity of the preparation has not been assessed.