Endogenous tripeptide antioxidant (supplement and research use)
Reduced glutathione
A major endogenous antioxidant tripeptide; systemic and intranasal supplementation effects remain inconsistently demonstrated.
- Evidence:
- Limited human evidence
- Status:
- Not FDA-approved
- Reviewed:
- 2026-08-03
Also known as: GSH, Reduced glutathione
What is Reduced glutathione?
A major endogenous antioxidant tripeptide; systemic and intranasal supplementation effects remain inconsistently demonstrated.
This profile is educational. It organizes publicly discussed research context for Reduced glutathione and related naming aliases — it is not a treatment guide.
Proposed mechanism
Primary cellular antioxidant and detoxification cofactor via glutathione peroxidase and reductase systems.
Mechanism language on PepGuide describes how researchers discuss pathways. Proposed mechanisms can change as evidence evolves.
Current research notes
Human evidence grade: Limited human evidence
Preclinical evidence grade: Moderate human evidence
Glutathione supplementation is studied for skin lightening, oxidative stress, and liver health. Oral bioavailability is debated (liposomal forms studied). Intranasal delivery is discussed but results are inconsistent and not robustly proven. Human evidence varies by indication and route.
Key uncertainties
- Effective systemic elevation via non-IV routes
- Skin lightening durability
Research areas being studied
- Oxidative stress
- Skin pigmentation research
- Liver health
Being studied for a topic is not the same as proven benefit in that topic. Prefer primary literature for study design, endpoints, and limitations.
Safety & side-effect notes
Reported or discussed adverse effects
- Generally well tolerated
- GI upset with oral forms
Additional risks & considerations
- Supplement quality variability
- Limited bioavailability orally
- Bronchospasm with nebulized forms in asthmatics
Regulatory status
Not FDA-approved
Marketed as supplement; IV form used clinically in some regions for acetaminophen toxicity (different context).
Regulatory framing here is educational and can lag policy changes. Check official sources for current status.
Frequently asked questions
What is Reduced glutathione?
A major endogenous antioxidant tripeptide; systemic and intranasal supplementation effects remain inconsistently demonstrated.
How does Reduced glutathione work (proposed mechanism)?
Primary cellular antioxidant and detoxification cofactor via glutathione peroxidase and reductase systems.
What is Reduced glutathione being researched for?
Reduced glutathione has been discussed in research contexts including: Oxidative stress, Skin pigmentation research, Liver health.
What does current evidence say about Reduced glutathione?
Limited human evidence. Glutathione supplementation is studied for skin lightening, oxidative stress, and liver health. Oral bioavailability is debated (liposomal forms studied). Intranasal delivery is discussed but results are inconsistent and not robustly proven. Human evidence varies by indication and route.
What safety considerations are noted for Reduced glutathione?
Reported or discussed considerations include: Generally well tolerated; GI upset with oral forms; Supplement quality variability; Limited bioavailability orally; Bronchospasm with nebulized forms in asthmatics. This is educational information, not medical advice.
Is Reduced glutathione FDA approved?
Not FDA-approved. Marketed as supplement; IV form used clinically in some regions for acetaminophen toxicity (different context).
References & sources
- Arjinpathana N et al. (2012). Glutathione supplementation and skin melanin index — J Clin Aesthet Dermatol. Evidence type: human.
Prefer interactive tools? Open the PepGuide library entry for Reduced glutathione or ask PepGuide AI.
Educational and research information only. PepGuide does not sell or prescribe peptides, diagnose conditions, or provide personalized medical advice. Evidence summaries may include early-stage, animal, or limited human research — none of that is a substitute for primary literature or clinician guidance.