STABILITY STUDIES OF EXTEMPORANEOUS ZINC SULFATE INJECTIONS FOR HOSPITAL USE

Abstract

Zinc is an important trace mineral that people need to stay healthy. Zinc sulfate injection is used as a supplement to intravenous solutions for patients who cannot take zinc orally. In Thailand, zinc sulfate injection is not commercially available, instead being aseptically prepared in extemporaneous preparation in individual hospitals. However, the stability of zinc sulfate injection was not studied. The objective of this study was to evaluate the stability of zinc sulfate injections prepared from different vehicles (sterile water and pH 2-3 sterile water adjusted with sulfuric acid) and sterilization methods (moisture sterilization and sterile by filtration). It was found that zinc sulfate injection had the greatest solubility in acidic condition and zinc sulfate injection 1 mg/mL was not precipitate at pH 2-9. The stability of zinc sulfate 6 formulas that have been stored at 40±2ºC, 75%±5%RH for 3 months by the standard analytical method described in USP 38, the results show that content of zinc did not change and still be in the standard level of 90.0-110.0% labeled amount. The stability study of zinc sulfate injection in various IV admixtures indicated that the percentage of zinc content did not decrease after mixing for 24 hours. In conclusion, the different vehicles and sterilization methods have no effect on content of zinc when storage in 3 months. Sterile water was recommended as vehicle and moisture sterilization as the sterilization method, because it is convenient and cost saving.