Glutathione[GSH; gamma-glutamyl-cysteinyl-glycine]
Compound snapshot
Class
Endogenous tripeptide antioxidant
FDA approved
No approved injectable indication for general wellness use
Clinical development
Phase 2
Last reviewed
September 2026
Research areas
Immune signalling / Inflammation / Longevity research
Regulatory status
Natural antioxidant; injectable wellness use is not FDA-approved
Internet attention
High
Registry query
Glutathione
A naturally produced three-amino-acid antioxidant found in nearly every cell. It is a true tripeptide, although it is primarily a core part of normal biochemistry rather than a peptide-hormone drug.
Reality check — what we actually know
Supported by human evidence
- This compound has completed human trials in at least one approved indication — see the regulatory section for what was actually approved.
Animal research only
- Essential endogenous defence against oxidative stress and maintenance of cellular redox balance
- Supports normal detoxification and recycling of other antioxidant systems
- Oral supplementation can raise body glutathione in some studies, while results vary by formulation and population
Mechanistically plausible
- Its cysteine thiol donates electrons to neutralise reactive oxygen species. Glutathione cycles between reduced GSH and oxidised GSSG, supports glutathione-peroxidase reactions and helps the liver conjugate selected compounds for elimination.
Common internet claims
- Online discussion frequently presents Glutathione as a proven treatment rather than a research compound.
Not established
- Human efficacy for the outcomes commonly claimed
- Optimal route, quantity and duration in humans
- Long-term human safety
Evidence distribution
Each band is a live PubMed search for Glutathione, filtered to that kind of study. Top is the strongest evidence; the base is reasoning, not proof. A band with no records means that kind of study has not been published for this compound yet.
Mechanism and reported findings
Its cysteine thiol donates electrons to neutralise reactive oxygen species. Glutathione cycles between reduced GSH and oxidised GSSG, supports glutathione-peroxidase reactions and helps the liver conjugate selected compounds for elimination.
- Essential endogenous defence against oxidative stress and maintenance of cellular redox balance
- Supports normal detoxification and recycling of other antioxidant systems
- Oral supplementation can raise body glutathione in some studies, while results vary by formulation and population
- Cosmetic skin-lightening claims, especially for injections, are not supported by an FDA-approved indication
Strength of the evidence: Its physiological role is firmly established. Evidence that supplementation improves broad wellness outcomes is mixed, and evidence for intravenous cosmetic use is limited. Benefits in a person with normal status should not be assumed from basic antioxidant biology.
Safety and known cautions
Compounded injections can cause severe reactions if sterility or raw materials are inadequate; injectable glutathione is not approved for skin lightening or general wellness. Oral products can cause gastrointestinal symptoms, and long-term use for specific conditions should be discussed with a clinician.
Evidence at a glance
No single score, on purpose. The line beside each bar shows how much reported outcomes vary between studies.
Development stage
- Discovery
- Preclinical
- Phase 1
- Phase 2Current
- Phase 3
- Regulatory review
- Approved