Glutathione is often a tripeptide that can be synthesized in all cells of the human body from its constituent amino acids L-cysteine, L-glutamic acid, and glycine. It's present in reduce concentrations in plasma and extracellular fluid, except in bile where concentrations are higher. Lower levels are found in the brain; https://glutathione-injection65543.bloggazza.com/37925894/a-simple-key-for-glutathione-injection-unveiled