OBJECTIVE:To study the stability of omeprazole sodium solution for injection under the influence of metal ion calcium and magnesium.METHODS:HPLC was adopted to determine the variation of the content of omeprazole sodium solution acted by metal ion calcium and magnesium of different concentrations in different time.The change in colour and luster was also observed.RESULTS:Omeprazole sodium solution tended to disintegrate rapidly along with the prolonging of time,and increase with the increasing of concentration;when Mg2+ was added,change in color was seen,with no degradation substance produced;when Ca2+was added,change in color was also seen,with white deposit produced.CONCLUSION:Ca2+ and Mg2+ show significant influence on the stability of omeprazole sodium solution.