Endogenous tripeptide
Glutathione
An endogenous tripeptide whose oral, topical, natural-health-product, compounded, and injectable contexts must be kept separate.
Why it is discussed
Antioxidant, wellness, and skin-related claims
Glutathione is discussed as an endogenous antioxidant and in oral, topical, inhaled, and injectable contexts. Small randomized trials have examined particular oral and topical preparations for skin-pigmentation outcomes; those findings do not transfer to injectable products. Regulatory status also varies by route, formulation, product, and claim. The existence of glutathione in the body—or in an authorized natural health product—does not establish that an injectable preparation is authorized, sterile, safe, or effective.
What it is
An antioxidant tripeptide made by the body.
Glutathione is formed from glutamate, cysteine, and glycine. Cells make it as part of their normal defense and metabolic systems. The reduced form is commonly abbreviated GSH; the oxidized form, in which two glutathione molecules are linked, is GSSG. These are related but chemically distinct forms.
How it works
A recyclable part of cellular redox chemistry.
Redox reactions transfer electrons between molecules. Glutathione participates in antioxidant reactions and the processing of certain reactive compounds. Its protective role depends on enzymes, recycling, and the cellular setting—not simply on having more glutathione everywhere.
Glutathione reductase uses reducing power from NADPH to convert GSSG back to GSH. Structural studies show how this recycling enzyme works. That is established biochemical function, not proof that a supplement or infusion reproduces a beneficial change in every tissue.
An endogenous antioxidant role does not establish claims of whole-body detoxification, skin lightening, disease prevention, or safe injection. Different routes and formulations require their own evidence and quality controls.
Scientific / evidence sources
Evidence at a glance
What is established—and what is not.
Route-, formulation-, product-, and claim-specific human evidence
Glutathione is an endogenous tripeptide, and small randomized trials have examined specific oral reduced-glutathione and topical oxidized-glutathione preparations for skin-pigmentation outcomes.
Endogenous biology and route-specific studies do not establish broad wellness or skin claims, injectable-product authorization, sterility, endotoxin control, or equivalence among oral, topical, compounded, and injectable preparations.
Regulatory status
Canada and the United States are checked separately.
No authorized injectable glutathione drug was identified in the current Drug Product Database review. Health Canada has reported unauthorized glutathione injections associated with excessive endotoxin; separately licensed natural health products do not authorize injection.
No FDA-approved injectable glutathione product was identified. FDA has reported adverse events and excessive endotoxin associated with dietary-grade glutathione used to compound sterile injectables.
Regulatory status describes product authorization and relevant regulatory context. It is not a complete legal opinion about possession, importation, prescribing, sale, or professional practice.
If you are reviewing a product report
The molecule profile and the testing report answer different questions.
This page summarizes evidence and regulatory context. A laboratory report may address identity, purity, or quantity for one submitted sample; it does not transfer clinical evidence or product authorization.