**5. Conclusion**

The HPLC/MS method has been developed for the determination of the antioxidant couple consisting of glutathione and ascorbic acid in pharmaceutical products. The use of a tandem of DAD and MSD detectors is substantiated. The method has been validated for accuracy, stability, and precision. The method has a low detection limit. The presence of foreign components in samples including sodium hydroxide, disodium EDTA, and benzyl alcohol does not impair the accuracy of the analysis. The method provides a fast, sensitive, accurate, and reproducible means of determining the antioxidant couple in pharmaceuticals. Preliminary special preparation of samples is not required.
