Switching Levothyroxine Generics Doesn't Affect TSH Levels, Study Finds MedPage Today Glutathione: Antioxidant Properties Dedicated to Nanotechnologies These highlights do not include all the information needed to use LEVOTHYROXINE SODIUM TABLETS safely and effectively. See full prescribing information for LEVOTHYROXINE SODIUM TABLETS. LEVOTHYROXINE SODIUM tablets, for oral use Initial Glutathione is the body's primary internal antioxidant, made using the amino acid cysteine, and it helps protect cells from oxidative stress. Beyond detoxification, research shows glutathione is involved in thyroid hormone metabolism,