Summary
Glutathione is a tripeptide made in every cell that neutralizes reactive oxygen species and detoxifies drugs and metabolites. A 6 month randomized trial of 54 adults found oral glutathione at 250 or 1,000 mg per day raised blood and cell glutathione stores by up to about 30%, while a 4 week trial found no change in oxidative stress markers, and no trial shows a clinical benefit for skin lightening, detoxification, or aging. Intravenous glutathione is compounded and given in clinics; the substance was nominated for the FDA 503A bulks list and has no final determination, and FDA has warned about compounded glutathione products with excessive endotoxin.
What is Glutathione?
Glutathione is a naturally occurring tripeptide (glutamate, cysteine, glycine), the main intracellular antioxidant; sold as oral supplements and compounded injections. It is also known as GSH, L-glutathione reduced, Gamma-glutamyl-cysteinyl-glycine, IV glutathione, Liposomal glutathione.
How does it work?
Glutathione donates electrons to neutralize peroxides through glutathione peroxidases, regenerates vitamins C and E, and conjugates with electrophilic toxins through glutathione S-transferases for excretion. Cysteine availability limits its synthesis, which is why N-acetylcysteine and glycine are used as precursors. Oral glutathione was long thought to be fully digested, but the 2015 trial showed body stores rise with sustained dosing. Proposed skin lightening works by shifting melanin synthesis toward lighter pheomelanin, a mechanism shown in cells with weak human support.
| Cluster | Longevity and mitochondrial |
|---|---|
| Routes | Oral capsule, liposomal, or sublingual (dietary supplement); Intravenous infusion or push (compounded, clinics); Intramuscular or subcutaneous injection (compounded); Inhaled (nebulized, studied in cystic fibrosis) |
| Conditions studied | Skin aging and cosmetic repair; Longevity and healthy aging |
| Record | v3, draft, verified Sep 22, 2026 |
What does the evidence say about Glutathione?
Two randomized trials address the basic question of whether oral glutathione raises levels. Richie et al. 2015 (54 healthy adults, 250 or 1,000 mg per day for 6 months) found dose dependent increases in glutathione in blood, red cells, lymphocytes, and buccal cells (up to about 30% to 35% at the high dose) and increased natural killer cell activity, with levels returning to baseline after a 1 month washout. Allen and Bradley 2011 (40 healthy adults, 500 mg twice daily for 4 weeks) found no change in oxidative stress biomarkers. No randomized trial demonstrates a clinical outcome for intravenous glutathione, and skin lightening claims rest on small, short trials with inconsistent results.
| Evidence type | Indexed studies | Participants (human) |
|---|---|---|
| Human randomized trials | 2 | 94 |
| Human observational studies | 0 | n/a |
| Animal studies | 0 | n/a |
| All indexed studies | 2 | 94 |
Human evidence
Richie 2015: 54 healthy non-smoking adults randomized to placebo, 250 mg, or 1,000 mg oral glutathione daily for 6 months; body stores rose in a dose and time dependent manner, with whole blood glutathione up about 30% and lymphocyte glutathione up about 35% at 1,000 mg, and natural killer cytotoxicity doubled at 3 months in the high dose group. Allen 2011: 40 healthy adults randomized to 500 mg twice daily or placebo for 4 weeks; no significant change in glutathione levels or oxidative stress markers. No published randomized trial of intravenous glutathione for any common clinic indication was identified.
Animal evidence
Rodent studies show glutathione depletion sensitizes tissues to oxidative and drug induced injury (the basis for N-acetylcysteine in acetaminophen overdose) and that glutathione or precursor supplementation protects liver, kidney, and lung in toxicity models. Animal data do not address the aging or cosmetic uses marketed to consumers.
Key studies
| Study | Design and population | Outcome | Grade |
|---|---|---|---|
| Randomized controlled trial of oral glutathione supplementation on body stores of glutathione2015 PMID 24791752 | Randomized, double blind, placebo controlled trial, 6 months plus 1 month washoutn = 54 Healthy non-smoking adults | Dose dependent increases in glutathione in whole blood, red cells, lymphocytes, and buccal cells (up to about 30% to 35% at 1,000 mg per day); natural killer cell activity doubled at 3 months in the high dose group | Evidence: Human RCT evidence |
| Effects of oral glutathione supplementation on systemic oxidative stress biomarkers in human volunteers2011 PMID 21875351 | Randomized, double blind, placebo controlled trial, 4 weeksn = 40 Healthy adults | No significant change in glutathione levels or oxidative stress biomarkers with 500 mg twice daily | Evidence: Human RCT evidence |
Conditions studied
| Condition | Grade | Note |
|---|---|---|
| Skin aging and cosmetic repair | Not graded | GHK-Cu (copper peptide) is the best studied peptide for skin, with cell and small human cosmetic studies showing increased collagen synthesis and improved skin appearance when applied topically. Injectable use has no clinical trial support. |
| Longevity and healthy aging | Not graded | No peptide has been shown to extend human lifespan. MOTS-c, humanin, and SS-31 (elamipretide) are mitochondrial peptides with rodent data and, for elamipretide, human trials in mitochondrial myopathy and Barth syndrome. Epitalon and FOXO4-DRI rest on animal or in vitro data. GLP-1 agonists have the strongest human outcome data for mortality relevant endpoints, through cardiovascular risk reduction. |
Is Glutathione legal in the United States?
FDA and compounding status
Glutathione is not an FDA approved drug. Oral glutathione is sold lawfully as a dietary supplement. Injectable glutathione is compounded from a bulk substance that was nominated for the FDA 503A bulks list and appears on the nominated substances lists pending a final determination; compounding continues under FDA's interim enforcement policy where state boards permit. FDA has issued warnings about compounded glutathione products containing high levels of endotoxin and about glutathione injections marketed for skin lightening, which is not an approved use.
WADA status
Not WADA prohibited. Not named on the current prohibited list. Athletes should still confirm against the list in force for their season.
Regulatory timeline
No regulatory events recorded.
What published studies of Glutathione used
Ranges below are reported from published studies and labeling only. PeptideAgent does not recommend doses or protocols.
Randomized trials used oral glutathione 250 mg or 1,000 mg per day for 6 months (Richie 2015) and 500 mg twice daily for 4 weeks (Allen 2011). No randomized trial establishes an intravenous or injectable dose for any clinic indication; IV doses used in clinics vary widely and are not evidence based.
Routes reported
| # | Route |
|---|---|
| 1 | Oral capsule, liposomal, or sublingual (dietary supplement) |
| 2 | Intravenous infusion or push (compounded, clinics) |
| 3 | Intramuscular or subcutaneous injection (compounded) |
| 4 | Inhaled (nebulized, studied in cystic fibrosis) |
What are the side effects and interactions of Glutathione?
Side effects
| # | Reported side effect |
|---|---|
| 1 | Oral: generally well tolerated; mild bloating or cramps reported occasionally |
| 2 | IV: flushing, nausea, and rare allergic reactions; asthma exacerbation reported with inhaled glutathione |
| 3 | Compounded injectable products have been recalled or warned about for excessive endotoxin, causing fever and chills after infusion |
| 4 | Long term safety of high dose supplementation and of skin lightening use is not established |
Interactions
| # | Interaction |
|---|---|
| 1 | No clinically significant interactions documented for oral use |
| 2 | Theoretical reduction in efficacy of some chemotherapy agents that act through oxidative stress; oncology patients should not use it without their oncologist's input |
| 3 | May interact with the metabolism of drugs that rely on glutathione conjugation (theoretical) |
Contraindications
| # | Contraindication |
|---|---|
| 1 | Active cancer treatment without oncologist approval (theoretical interference with therapy) |
| 2 | Asthma for inhaled forms |
| 3 | Pregnancy and breastfeeding for injectable forms (no data) |
| 4 | Known hypersensitivity to glutathione or product excipients |
How do people access Glutathione legally?
Typical cost: Compounded injectable glutathione through licensed telehealth programs runs about 75 to 100 USD per month; a glutathione injection or IV add-on at an IV clinic is about 35 to 50 USD. Oral supplements are sold over the counter. Prices checked 2026-09-22 on published provider and pharmacy price pages.
Verified access options
Step 1
Over the counter dietary supplement, no prescription needed.
Step 2
Prescription from a licensed provider filled by a 503A compounding pharmacy for injectable glutathione, where the state board permits it.
Step 3
Clinic or telehealth programs offering IV or injectable glutathione.
Access paths are verified against public regulatory records and prescriber licensing. We never list unlicensed vendors.
Compare Glutathione
What's actually offered, and what that means for you
Licensed compounding pharmacies, clinics, and telehealth prescribers openly offer many unapproved peptides, and prescribers write prescriptions for them. Glutathione is not FDA approved. It is a nominated bulk substance FDA has not finished evaluating, and pharmacies compound it under FDA's interim policy where state boards permit, without any FDA finding on its safety or quality. [3] [9]
Enforcement is uneven. FDA mostly acts through warning letters to compounders and online sellers, Category 2 safety listings, and import alerts that let it detain shipments, rather than stopping every pharmacy. State pharmacy boards oversee pharmacies day to day, and their rules differ. [4] [10] [11] [12] [13]
What changes for you
- No FDA review of the product: FDA does not check a compounded drug's safety, effectiveness, or quality before it is sold. [4]
- Identity, purity, sterility, and dose accuracy can vary from batch to batch. [12]
- Insurance rarely covers it, so you usually pay cash.
What to check
Before you accept a compounded product, check for:
- A 503A pharmacy licensed in your state (your state board of pharmacy publishes license lookups). [4]
- A real evaluation by a licensed prescriber, not just an online form.
- A certificate of analysis for the specific batch.
Frequently asked questions
Is glutathione legal, and is it FDA approved?
Oral glutathione is a lawful dietary supplement. Injectable glutathione is not FDA approved; it is compounded from a bulk substance that has been nominated for the FDA 503A bulks list without a final rule, so clinics offer it under interim enforcement discretion. FDA has warned about compounded products with high endotoxin and about marketing injections for skin lightening. [3] [4]
Does oral glutathione actually get absorbed?
Yes, with sustained dosing. In a 6 month randomized trial of 54 adults, 1,000 mg per day raised whole blood glutathione by about 30% and lymphocyte glutathione by about 35%, and levels fell back after stopping. A shorter 4 week trial at 1,000 mg per day found no change, so time and dose matter. [1] [2]
Does glutathione work for skin whitening?
The evidence is weak. The mechanism is shown in cells, and a few small short trials of oral or topical glutathione reported slight lightening that was inconsistent and not durable. No randomized trial supports intravenous glutathione for skin lightening, FDA has warned against marketing injections for that purpose, and the practice is unregulated in many clinics. [1] [4]
What are the side effects of glutathione?
Oral glutathione was well tolerated over 6 months in the largest trial, with occasional mild stomach complaints. IV glutathione can cause flushing, nausea, and rarely allergic reactions, and compounded products contaminated with endotoxin have caused fever and chills after infusion. Inhaled glutathione can trigger bronchospasm in people with asthma. [1] [4]
How is glutathione taken?
Trials used oral doses of 250 to 1,000 mg per day, taken daily for months. Clinics give it intravenously or by injection at doses that vary widely and have not been tested in randomized trials. Precursors such as N-acetylcysteine and glycine are another way to raise glutathione that has its own evidence base. [1] [2]
How much does glutathione cost?
Compounded injectable glutathione through licensed telehealth programs is about 75 to 100 USD per month, and a glutathione injection or IV add-on at an IV clinic is about 35 to 50 USD. Oral supplements are sold over the counter. Prices were checked on 2026-09-22 and change often. [3] [6] [7] [8]
Is glutathione banned by WADA?
No. Glutathione is a naturally occurring antioxidant and is not listed in any section of the WADA Prohibited List as of 2026. Athletes should note that IV infusions above 100 mL in a 12 hour period are prohibited under section M2 regardless of the substance, unless given in a hospital setting or with an exemption. [5]
Glutathione vs NAC: which raises glutathione better?
Both work. N-acetylcysteine supplies cysteine, the rate limiting building block, and has decades of clinical use. Oral glutathione itself raised body stores by about 30% over 6 months in a randomized trial. Head to head comparisons are lacking, and neither has been shown to improve aging or skin outcomes in a rigorous trial. [1] [2]
Decisions about starting, stopping, or combining any treatment belong with a licensed clinician who knows your history.
Sources
Numbered citations above point to these primary sources. PubMed entries link to the indexed abstract.
- [1]Richie JP Jr et al. Randomized controlled trial of oral glutathione supplementation on body stores of glutathione. Eur J Nutr 2015PubMed 24791752, 2015
- [2]Allen J, Bradley RD. Effects of oral glutathione supplementation on systemic oxidative stress biomarkers in human volunteers. J Altern Complement Med 2011PubMed 21875351, 2011
- [3]FDA: Bulk drug substances used in compounding under section 503A of the FD&C Act (links to the Category 1, 2, and 3 lists and the bulks list)FDA, 2026
- [4]FDA: Compounding and the FDA, questions and answers (including risks of compounded drugs and enforcement policy for nominated bulk substances)FDA, 2026
- [5]WADA Prohibited List (including section M2 on intravenous infusions)WADA, 2026
- [6]Licensed telehealth provider price page for compounded glutathione injections, accessed 2026-09-22
- [7]Second licensed telehealth provider price page for compounded glutathione injections, accessed 2026-09-22
- [8]Registered nurse staffed IV clinic published price menu (NAD+ and glutathione), accessed 2026-09-22
- [9]FDA guidance: Interim policy on compounding using bulk drug substances under section 503AFDA
- [10]FDA: Compounding inspections, recalls, and other actions (warning letters to compounders)FDA
Cite this page
Free to cite and quote with a link. Data is licensed CC BY 4.0 with attribution to PeptideAgent.
- APA style
PeptideAgent. (2026, September 22). Glutathione: evidence, legality, and access. https://peptideagent.ai/peptides/glutathione- HTML link
<a href="https://peptideagent.ai/peptides/glutathione">Glutathione: evidence, legality, and access</a>, PeptideAgent, updated September 22, 2026.