Glutathione
Also known as GSH, L-Glutathione reduced, Gamma-glutamylcysteinylglycine, Tationil
Glutathione is a tripeptide of glutamate, cysteine and glycine that every cell makes as its main antioxidant. People use it by injection, IV, oral, liposomal or nebulized routes for oxidative stress, liver support, immune health and skin lightening.
Reviewed by the amino101 editorial team. , first published .
Quick start
What people commonly do. Not a prescription.- Typical dose
- 200 to 600 mg (injectable); 250 to 1000 mg daily (oral)
- How often
- 2 to 3 times weekly (injectable); daily (oral)
- Where
- Subcutaneous or intramuscular, belly or thigh; IV in clinics; oral liposomal or sublingual for daily use
- Timing
- injections after workouts or before sleep; oral liposomal away from protein meals
- Effects timeline
- energy and recovery 1 to 2 weeks, skin tone changes 4 to 12 weeks, measured blood glutathione rise 1 to 6 months on oral
- Storage
- fridge 2 to 8 C once mixed, use within 1 to 2 weeks; it oxidizes quickly in solution, discard if it discolors or smells of sulfur
- Cycle length
- ongoing, or 8 to 12 week courses
- Break between
- none required; many people pause for a few weeks between courses to see whether they notice a difference
Overview
Glutathione is technically a peptide, though an unusual one: the glutamate is joined through its side chain rather than the normal backbone bond, which protects it from most peptidases. It is present at high concentration in virtually every cell, where it neutralizes reactive oxygen species, recycles vitamins C and E, and helps the liver bind and excrete toxins and drug metabolites. Levels fall with age, illness, poor diet and heavy alcohol use, and low glutathione is associated with a long list of chronic conditions.
The problem with taking glutathione is getting it into cells. Standard oral glutathione is largely broken down in the gut, although a few controlled studies have shown modest increases in blood and tissue levels with sustained daily dosing. Liposomal and sublingual forms improve absorption. Intravenous glutathione delivers high plasma levels but the peptide is cleared quickly and cells still have to take up the components. N-acetylcysteine, which supplies the limiting amino acid cysteine, is a well studied way to raise glutathione from the inside.
Human evidence exists for several uses. IV glutathione is used as an approved adjunct to cisplatin chemotherapy in some countries to reduce nerve toxicity. Trials for Parkinson's disease, cystic fibrosis (nebulized) and fatty liver have shown small or inconsistent benefits. Skin lightening via IV glutathione is popular in parts of Asia but poorly supported and carries real risks from unregulated infusions. Injectable use for general wellness is common in the peptide community, usually 200 to 600 mg several times a week.
How it works
Glutathione works as a reducing agent. The thiol group on its cysteine donates electrons to neutralize free radicals and peroxides, and the enzyme glutathione peroxidase uses it to break down hydrogen peroxide and lipid peroxides. Once oxidized, two glutathione molecules join as GSSG and are recycled back by glutathione reductase using NADPH. In the liver, glutathione S-transferases attach it to toxins and drug metabolites so they can be excreted. It also keeps protein thiols in their correct state, supports mitochondrial function, and regulates the redox-sensitive signaling that controls inflammation and cell survival. Its effect on skin pigmentation comes from inhibiting tyrosinase and shifting melanin production toward the lighter pheomelanin form.
Where the research stands
Chemotherapy nerve protectionStrong evidence
- Cisplatin and oxaliplatin neurotoxicity. Multiple randomized trials of IV glutathione reduced nerve damage without reducing tumor response, which is the basis for its approval in some countries.
Raising body glutathione storesModerate evidence
- Oral supplementation. A six month randomized trial of 250 to 1000 mg daily raised blood and cell glutathione and improved natural killer cell function in healthy adults.
- IV and injectable for general wellness. Raises plasma levels reliably, but there is no controlled evidence that this improves any health outcome in healthy people.
Skin lighteningEmerging
- Oral or topical for pigmentation. Small trials in Asian populations show measurable lightening over 4 to 12 weeks that reverses on stopping; IV lightening has caused serious harm from unregulated clinics.
Neurological and lung conditionsWeak or mixed
- Parkinson disease. Controlled trials of IV and intranasal glutathione showed marginal or no clinical benefit.
- Cystic fibrosis (nebulized). Randomized trials are split, some showing improved lung function measures and some showing none.
- Fatty liver. Small open label oral studies reported lower liver enzymes; no controlled confirmation.
- human RCTSix months of oral glutathione at 250 to 1000 mg daily increased blood and tissue glutathione levels and improved natural killer cell function in healthy adults.
- human RCTIV glutathione reduced cisplatin-induced neurotoxicity in cancer patients without reducing chemotherapy efficacy.
- human pilotOral glutathione produced measurable skin lightening in small trials in Asian populations over 4 to 12 weeks.
- human RCTIntranasal or IV glutathione in Parkinson's disease showed only marginal or no clinical benefit in controlled trials.
- human RCTNebulized glutathione improved lung function measures in some cystic fibrosis trials but not others.
Rodent and in vitro mean no human data for that finding. Human pilot means small, often uncontrolled. Human RCT means randomized and controlled. Clinical means an approved drug with regulatory data.
Levels over time
Modeled from the half-life. Illustrative, not measured.A half-life of 12 min against dosing every 24 h means each dose has cleared before the next. Nothing stacks; you start from zero every time, and the tissue effect is what carries over.
The blood spike is short, so the point of any dose is what the cells take up and rebuild internally, which is why regular dosing over weeks matters more than the size of any single injection.
Glutathione dosage and protocols
Injectable use is usually 2 to 3 times weekly, either ongoing or in 8 to 12 week courses. Oral is taken daily and needs months to change blood levels. There is no loading or tapering, and no evidence that cycling matters, so people mostly stop when they are not sure it is doing anything.
| Goal | Dose | Frequency | Route |
|---|---|---|---|
| General antioxidant support, injectable | 200 to 600 mg | 2 to 3 times weekly | Subcutaneous or intramuscular |
| IV clinic infusion | 600 mg to 2 g | weekly or as scheduled | Intravenous, slow push or drip |
| Daily oral | 250 to 1000 mg | once daily | Oral, liposomal or sublingual preferred |
| Skin tone | 500 to 1000 mg | once daily | Oral |
| Supporting natural production | 600 to 1200 mg NAC plus glycine | daily | Oral |
Oral liposomal glutathione absorbs better away from protein meals. Injections are often timed after training or before bed, though there is no data that timing changes the result. High dose antioxidants right around workouts may blunt some training adaptations, so some people keep injections on rest days.
Injectable community protocols commonly report 200 to 600 mg two to three times weekly. IV clinics use 600 mg to 2 g. Oral doses are typically 250 to 1000 mg daily.
Dose calculator
U-100 insulin syringeUnits are a volume on the syringe, not an amount of peptide. Concentration changes every time you change the water volume. The standalone calculator explains the math.
| Vial | Suggested water | Concentration | Low dose draw |
|---|---|---|---|
| 600 mg | 3 mL | 200 mg/mL | 100 units |
| 1500 mg | 5 mL | 300 mg/mL | 66.7 units |
How to reconstitute Glutathione
- 1
Wash your hands and wipe the work surface. Swab both vial stoppers with alcohol and let them dry.
- 2
Pick the water volume with the calculator above and write it on the vial. The concentration means nothing without it.
- 3
Draw the bacteriostatic water into a mixing syringe.
- 4
Insert at an angle and let the water run down the inside wall. Never squirt it straight onto the powder.
- 5
Swirl gently or leave it to dissolve. Do not shake.
- 6
Label with the date and water volume. Store in the fridge at 2 to 8 C and use within about 4 weeks.
- 7
Unmixed vials keep for months in the fridge and longer in the freezer, sealed and out of light.
- Full walkthrough with syringe reading and site rotation: reconstitution guide.
- ✓White, fluffy cake
Lyophilized powder should look like a small white puck or fluffy cake at the bottom of the vial. That is a proper freeze-dry.
- ✓Clear after mixing
Once dissolved the solution should be water-clear with nothing floating in it.
- !Slight clumping
Small clumps that dissolve with gentle swirling are fine. Shipping compacts powder.
- ✕Collapsed or melted
Powder stuck to the sides, glassy, or shrunken means it got hot in transit. Contact the vendor.
- ✕Cloudy or particles
Persistent cloudiness or visible particles after mixing means degraded or contaminated product. Do not use it.
- Week 1 to 2
Some people report more energy, better sleep or faster recovery; others feel nothing, and a sulfur smell or taste after injection is common.
- Week 4 to 8
Skin tone changes, if any, start to show; injectable users usually decide by now whether they notice a difference.
- Month 3 to 6
Measurable rises in blood glutathione from oral dosing appear on this timeline in the controlled trial, with the largest change at 6 months.
Interactions and stacking
NAD+synergistic
NADPH is what recycles oxidized glutathione back to its active form, so the two are paired in mitochondrial protocols.
SS-31compatible
SS-31 protects the mitochondrial membrane while glutathione handles free radicals in the rest of the cell; no interaction, just different targets.
MOTS-ccompatible
Used together in longevity and metabolic stacks; no known interaction.
Vitamin Csynergistic
The two antioxidants recycle each other; oral vitamin C has been shown to raise glutathione levels on its own.
N-acetylcysteinesynergistic
NAC supplies the cysteine that limits glutathione synthesis and is a cheaper, well studied way to raise levels from the inside.
Chemotherapycaution
Used deliberately alongside cisplatin in trials, but for other chemotherapy agents an antioxidant could in theory interfere; this needs the oncologist's input, not a self-directed decision.
Sulfite-containing products and asthmacaution
Injectable glutathione has triggered bronchospasm in rare cases, and people with sulfite sensitivity or asthma should be careful with injectable and nebulized forms.
Alcoholcompatible
Heavy drinking depletes glutathione and people use it around drinking for that reason; it does not prevent alcohol harm.
NAD+ supports the enzyme that recycles oxidized glutathione, so the two are commonly paired in mitochondrial protocols.
SS-31 protects mitochondrial membranes from oxidative damage while glutathione handles free radicals in the rest of the cell.
Used together in longevity and metabolic protocols targeting mitochondrial health.
Safety
- ▲Sulfur smell or taste after injection
- ▲Nausea or stomach cramps, more with oral doses
- ▲Injection site pain or bruising
- ▲Skin rash or flushing
- ▲Bronchospasm in rare cases, mostly in people with asthma or sulfite sensitivity
- ▲Kidney and liver problems reported from unregulated high dose IV lightening treatments
- ▲Plain oral glutathione has poor absorption; look for liposomal or sublingual forms, or use NAC to support natural production.
- ▲IV glutathione for skin lightening is associated with reports of kidney and liver problems, skin rashes and serious reactions from unregulated clinics.
- ▲It oxidizes fast once reconstituted, so old solution may be inactive.
- ▲High dose antioxidants can blunt some of the beneficial adaptations to exercise.
- ▲People with sulfite sensitivity or asthma should be cautious with injectable forms, which can trigger bronchospasm in rare cases.
- ■Wheezing, chest tightness or trouble breathing after a dose
- ■Hives, swelling or other signs of an allergic reaction
- ■Unexplained abdominal pain, dark urine or jaundice
- ■You are starting chemotherapy and have not cleared it with the oncologist
- ■The reconstituted solution has discolored or smells strongly of sulfur, which means it has oxidized
Community poll
Self-reported by visitors. Not clinical evidence.Glutathione: frequently asked
Is glutathione really a peptide?
Yes, it is a tripeptide, though with an unusual bond that makes it resistant to normal peptide digestion. It is included in peptide databases because it is dosed and sold alongside other injectable peptides, but it is also widely available as a regular supplement.
Does oral glutathione work?
Older studies said no, but a six month randomized trial found daily oral glutathione did raise blood and cell levels. The effect is modest and slow. Liposomal formulations absorb better. If your goal is simply to raise glutathione, N-acetylcysteine plus glycine is a cheaper and well supported alternative.
Will it lighten my skin?
Oral and IV glutathione have shown lightening effects in small studies, mainly in people with darker skin tones, by shifting melanin production. The effect reverses when you stop. IV lightening treatments from unregulated providers have caused serious harm and are not recommended.
Injectable versus IV, what is the difference?
IV delivers the full dose to the blood immediately, which is why clinics use it. Subcutaneous or intramuscular injection is slower and used at home. Both give a short plasma spike. Neither route has strong evidence for general wellness use in healthy people.
References
- Randomized controlled trial of oral glutathione supplementation on body stores of glutathione. European Journal of Nutrition, 2015
- Glutathione in the prevention of cisplatin-induced neurotoxicity (review of clinical trials). Annals of Oncology, 1997
- Glutathione as a skin whitening agent: facts, myths, evidence and controversies (review). Indian Journal of Dermatology, Venereology and Leprology, 2016
- Glutathione: overview of its protective roles, measurement, and biosynthesis (review). Molecular Aspects of Medicine, 2009