What is Glutathione?

Glutathione: Endogenous tripeptide (glutamate-cysteine-glycine) and the body's main intracellular antioxidant. The sources cited here most often discuss it for: Raises body glutathione; Skin lightening, mixed trials; Fatty liver, small pilot. Evidence label: Trial-backed.

Type
Peptide
Family
Longevity & Mitochondria
Evidence label
Trial-backed (4 of 5)
Regulatory status
Glutathione is in FDA's 503A Category 1, bulk substances under evaluation for compounding, as of the May 14, 2026 list.
Goals discussed
Longevity & Cellular Aging, Skin & Glow, Heart, Liver & Kidney
Also called
GSH, Tathion, Master antioxidant, IV Glutathione drip, L Glutathione
Last reviewed
2026-10-11
  • Endogenous tripeptide (glutamate-cysteine-glycine) and the body's main intracellular antioxidant; sold as an oral supplement and used as compounded IV/IM injections; not FDA-approved as a drug for skin lightening or other uses, and FDA has warned about contaminated compounded injectable glutathione.12

Regulatory status Glutathione is in FDA's 503A Category 1, bulk substances under evaluation for compounding, as of the May 14, 2026 list. 3

FDA is aware of reports of at least 30 patients who experienced adverse events following the administration of intravenous (IV) glutathione alone or in combination with other ingredients.

US Food and Drug AdministrationRegulator, FDA reminds compounders not to use dietary supplement grade glutathione for injectables2

August 2026 FDA notice about IV glutathione compounded from a supplement-grade ingredient with elevated endotoxin.

What is Glutathione researched for?

The three outcomes most discussed for Glutathione in the sources below, as those sources report them. humanpeptides.fyi makes no claims of its own: a listed benefit can be unproven or can have failed in trials, and the label on each line says which.

  1. Raises body glutathione

    • Raises body glutathione stores: 6-month RCT (n=54) of 1,000 mg/day oral GSH raised levels ~30-35% in blood cells/plasma and 260% in buccal cells; returned toward baseline after washouthuman RCT14

    Longevity & Cellular Aging

  2. Skin lightening, mixed trials

    • Skin lightening: 4-week RCT (n=60) of 500 mg/day oral GSH reduced melanin index at some sites vs placebo; a later 12-week Indonesian RCT of a GSH combination found no significant overall improvementhuman RCTs, mixed567

    Skin & Glow

  3. Fatty liver, small pilot

    • Fatty liver: open-label pilot (n=34) of 300 mg/day oral GSH for 4 months lowered ALT (~13%), triglycerides, free fatty acids and ferritin in NAFLDhuman, uncontrolled89

    Heart, Liver & Kidney

What do researchers and users say about Glutathione?

The current clinical evidence of intravenous glutathione for skin lightening is limited to a single study with a dubious study design and apparently flawed analysis of results, casting doubt on the drug’s efficacy and reported adverse effects.

Sonthalia S, Jha AK, Lallas A, Jain G, Jakhar D Researchers 10

Dermatology review abstract on injectable glutathione used for skin lightening.

And yes, the glowy skin will fade once you stop using it. Not immediately obviously but after a few weeks, the skin will fade back to its original color

Anonymous user, r/30PlusSkinCare User report 11

One user's self-report about IV glutathione for skin lightening; anecdotal.

What side effects of Glutathione are reported?

  • Compounded IV glutathione linked to fever, chills, shock-like symptoms and hospitalizations from endotoxin contamination; recalls issued212
  • IV use for skin lightening lacks safety data; reports of liver/kidney injury, severe skin reactions1314
  • Intravenous glutathione has been linked to anaphylaxis and liver toxicity, made worse by the lack of standardized protocols.review15
  • Japanese prescribing information for oral glutathione lists rash, loss of appetite, nausea or vomiting and stomach pain as the most common adverse reactions.drug label (Japan)16
  • In 2026, at least 30 patients had adverse events after IV glutathione compounded from a supplement-grade ingredient; endotoxin exposure can also cause muscle pain, headache, low blood pressure and death.FDA alert2
  • Some users of skin-lightening glutathione report more sun sensitivity, heat intolerance or a rise in uric acid.anecdotal17

What do peptide guides say about Glutathione?

  • Dr. Axe Dr. Axe describes glutathione, or GSH, as a three-amino-acid peptide the body makes itself, calls it the master antioxidant, and says sulfur-rich foods like garlic, onions and broccoli help cells make more. 18
  • NCBI PMC A 2018 dermatology review calls widespread injectable glutathione for skin lightening unjustified, noting some regulators have issued bans or advisories and that parenteral glutathione is approved only for severe liver disorders and chemotherapy nerve toxicity. 10
  • NCBI PMC A 2025 narrative review found oral glutathione lowered melanin significantly but variably with few side effects, while topical forms improved melanin and skin texture with less consistent staying power. 15
  • NCBI PubMed A 6-month randomized trial of daily oral glutathione found natural killer cell activity more than doubled versus placebo at 3 months in the higher-intake group, alongside rises in body glutathione stores. 19
  • Kusuri-no-Shiori (RAD-AR Japan) Japanese drug information lists oral glutathione (brand Tathion) as an approved prescription medicine for drug or metal poisoning, cyclic vomiting, severe pregnancy vomiting and pregnancy-induced hypertension. 16

What does the research say, system by system?

Body & tissues2
  • Liver (ALT/triglyceride reduction in NAFLD pilot)9
  • Skin (melanin index)5
Hormones & physiology1
  • Boosting glutathione via precursors (GlyNAC) in older adults reduced oxidative stress, inflammation and insulin resistancehuman pilot + RCT; precursor, not GSH itself2021
Cells & mitochondria1
  • Glutathione deficiency linked to mitochondrial dysfunction in aging; GlyNAC (precursors) RCT in 24 older adults raised muscle/RBC GSH and improved mitochondrial fatty-acid oxidation and aging hallmarkshuman RCT, precursor21
Brain, mood & sleep2
  • Parkinson's disease: intranasal GSH safe in phase I/IIa (n=30), but phase IIb (n=45) found no benefit over placebohuman RCTs2223
  • GlyNAC pilot reported improved cognition (precursor)20
Weight & metabolism2
  • Lowered triglycerides and NEFA in NAFLD pilot9
  • GlyNAC improved insulin resistance in older adults (precursor)20
Muscle1
  • GlyNAC (precursor) improved muscle strength and physical function in older adultshuman RCT21
Also notable1
  • Philippine FDA advisory calls IV glutathione for skin lightening unsafe14

How strong is the evidence for Glutathione?

Trial-backed

Human RCTs for oral supplementation (modest, mixed outcomes); IV use poorly supported and has safety warnings

Larger randomized human trials exist, positive or negative, but no US approval for the uses discussed. How tiers work

Questions about Glutathione

What is Glutathione?

Endogenous tripeptide (glutamate-cysteine-glycine) and the body's main intracellular antioxidant.

Is Glutathione FDA-approved?

Glutathione is in FDA's 503A Category 1, bulk substances under evaluation for compounding, as of the May 14, 2026 list.

What is Glutathione researched for?

The sources cited on this page most often discuss three outcomes: Raises body glutathione; Skin lightening, mixed trials; Fatty liver, small pilot. Each line above shows what the source reports and how strong that evidence is.

What side effects of Glutathione are reported?

Reported in the cited sources: Compounded IV glutathione linked to fever, chills, shock-like symptoms and hospitalizations from endotoxin contamination; recalls issued; IV use for skin lightening lacks safety data; reports of liver/kidney injury, severe skin reactions; Intravenous glutathione has been linked to anaphylaxis and liver toxicity, made worse by the lack of standardized protocols. The list is not complete, and few listed risks does not mean a compound is safe.

How strong is the evidence for Glutathione?

Evidence label: Trial-backed. Human RCTs for oral supplementation (modest, mixed outcomes); IV use poorly supported and has safety warnings.

What else is Glutathione called?

Names used for it include GSH, Tathion, Master antioxidant, IV Glutathione drip, L Glutathione.

Does humanpeptides.fyi recommend Glutathione?

No. humanpeptides.fyi makes no claims and no recommendations of its own. It summarizes and links to what others have published and posted. Nothing here is medical advice; talk to a licensed clinician.

Before you go in

humanpeptides.fyi is an educational index for adults. It summarizes and links to what others have published and reported about peptides and related compounds studied or used in humans. It is not medical advice and gives no dosing guidance. Many listed compounds are not approved for human use, and listing one is not a recommendation. Anecdotes are unverified. Images are AI-generated. By continuing, you agree to the Disclaimer and Terms of Use and the Privacy Notice.

Leave

Your answer is saved only in this browser.