Glutathione
Also known as: GSH, L-Glutathione, Reduced Glutathione
Lower numbers = closer to natural. Higher numbers = more enhanced.
Why this rating?
Glutathione is the body's naturally produced "master antioxidant" found in every cell. Supplementing glutathione simply supports natural detoxification and antioxidant pathways. It does not enhance muscle building, athletic performance, or hormonal function. Used for liver support, general antioxidant health, and (off-label) cosmetic skin-lightening. Oral forms are available as an over-the-counter supplement; IV/injectable forms require a prescription or compounding pharmacy and are not FDA-approved for cosmetic use. Not WADA prohibited. Rated 1 as it is essentially supporting the body's natural processes with no performance-enhancing effects.
Overview
The body's "master antioxidant" used for detoxification and oxidative stress reduction. Critical for liver health and cellular protection.
Important Warnings
- •Oral glutathione is poorly absorbed. IV, liposomal or NAC precursor is more reliable
- •Heavy antioxidant dosing right around training may slightly blunt exercise adaptations (hormesis)
- •Skin-lightening use is off-label, temporary and reverses on discontinuation
- •Injectable/IV use carries infection and (rarely) allergic-reaction risk. Use sterile technique
- •Cosmetic IV glutathione is not FDA-approved; regulators (e.g. Philippines FDA Advisory No. 2019-182) have linked unregulated/high-dose injections to Stevens-Johnson syndrome and kidney/liver/nervous-system toxicity. Use only licensed providers with pharmaceutical-grade product
Purpose & Use Cases
Liver Detoxification
Supports liver detoxification pathways, especially during cycles.
Antioxidant Protection
Neutralizes free radicals and reduces oxidative stress.
Skin Lightening
Can lighten skin tone (popular cosmetic use).
Benefits
- Powerful antioxidant protection
- Liver detoxification support
- Immune system support
- Skin health benefits
- Cellular protection
Good to Know
The master antioxidant: and that cuts both ways
Glutathione (a glutamate-cysteine-glycine tripeptide) is the body's main endogenous antioxidant and the workhorse of Phase II liver detox. But blanket high-dose antioxidant supplementation timed around training can slightly blunt the adaptive (hormetic) response to exercise: the reactive oxygen species a hard workout produces are part of the growth and mitochondrial-adaptation signal. Same nuance as megadosing vitamin C/E: mopping up all the oxidative stress can dull the very adaptation you trained for. Keep heavy antioxidant dosing away from the immediate post-workout window if maximising adaptation matters.
Oral glutathione is poorly absorbed
Swallowed GSH is largely broken down in the gut, so oral capsules raise blood levels unreliably. IV, injectable and liposomal forms work better, and precursors like NAC (plus glycine) are often a more cost-effective way to raise the body's own glutathione. This is why clinics give it IV.
Skin-lightening is real but temporary and off-label
High-dose (usually IV) glutathione shifts melanin production toward the lighter pheomelanin and inhibits tyrosinase, producing a lightening effect. It is cosmetic, not a licensed use, and reverses once you stop.
Not hormonal, not banned
Glutathione does not touch testosterone, IGF-1 or any performance pathway, and it is not on the WADA Prohibited List. It is purely a health/antioxidant support compound.
Dosage Guidelines
| Route | Typical Dose | Frequency | Cycle |
|---|---|---|---|
| IV infusion | 1200 – 2400 mg/week | 1-3x weekly IV/IM sessions (600-1200mg per session; 2x/week is the most common clinic protocol). Oral or liposomal forms are usually dosed daily instead (roughly 250-500mg/day), not on this weekly IV schedule. | 5 – 15 wk |
| Intramuscular (IM) injection | 1200 – 2400 mg/week | Typically 2-3x/week (sometimes daily short courses) at 200-600mg per shot, since IM injection volume per site is limited (~2-5mL) compared to a slow IV drip - clinics offer it as a needle-based alternative to IV using roughly the same weekly mass but split. | 4 – 12 wk |
| Oral (capsule/tablet) | 250 – 500 mg/day | Once or twice daily, ideally on an empty stomach; some cosmetic combination products go higher (e.g. 2400mg/day paired with 300mg L-cystine) but that is a specific proprietary formula, not the general standard | 4 – 12 wk |
| Liposomal oral | 500 – 1000 mg/day | Once daily, typically with or without food per product label | 4 – 12 wk |
| Topical (cream/lotion/soap) | 0.1-2% cream/lotion/soap | Applied 1-2x daily to face/body | 8 – 12 wk |
Dosing depends on how it's administered. Pick your route in the calculator to score the one you use.
IV/IM protocols (600-1200mg per session, 1-3x/week, often run as a 10-15 session course) are aesthetic/med-spa convention rather than a single RCT-defined clinical standard, treat as community/practice-derived dosing, not clinical guidance. The one placebo-controlled RCT on oral use (Arjinpathana & Asawanonda, 2012) dosed 500mg/day (250mg twice daily) for 4 weeks and found modest, reversible skin lightening. Oral glutathione has poor absorption, so IV, injectable, or liposomal forms are preferred when raising blood levels is the goal; NAC (a glutathione precursor) is a cheaper alternative. Cosmetic IV glutathione is not FDA-approved in the US.
IM is used both as a cosmetic med-spa alternative to IV (smaller per-shot volume so dosed more often for a similar weekly total) and in distinct clinical contexts with actual published protocols: 600mg/day IM on days 2-5 of chemotherapy as an antioxidant adjunct, and 600mg IM every other day for two months in male-infertility trials (semen-quality endpoints, not cosmetic).
The only placebo-controlled oral RCT (Arjinpathana & Asawanonda 2012) used 500mg/day (250mg twice daily) for 4 weeks and found modest, reversible skin-lightening in sun-exposed skin; RxList lists a general oral dose range of 50-600mg/day with 250mg once daily as a common label figure. Oral glutathione has poor systemic bioavailability - it's substantially broken down by gut peptidases and lacks a dedicated cellular uptake carrier - so blood-level increases are unreliable versus IV/IM; NAC (a precursor) or liposomal formulations are often preferred when raising glutathione status is the real goal.
Liposomal encapsulation (and newer proliposome/ester forms like glutathione monoethyl ester) is marketed to improve oral absorption versus plain capsules by protecting the tripeptide from gut-peptidase breakdown, and lab/PK work supports enhanced stability and cell penetration for these delivery forms. However, no head-to-head clinical trial was found establishing a validated liposomal mg/day dose for skin-lightening or antioxidant endpoints - the 500-1000mg/day range reflects common commercial product labeling and community practice (roughly 1-2x the standard oral dose, on the logic that even improved.
0.1-2% glutathione (or oxidized glutathione/GSSG) cream, lotion, or soap, applied 1-2x/day. Concentration-based, not a systemic mass dose, so it isn't scorable on a mg/day or mg/week basis. Study concentrations range from 0.1% up to 2% GSSG lotion (Watanabe et al., applied twice daily for 10 weeks) and a systematic review also cites 2.0% oxidized glutathione producing measurable skin-brightening in sun-exposed areas over similar timeframes; a comparison of 0.5% vs 0.1% found the higher concentration more effective over 8 weeks.
Biphasic after IV dosing: a fast ~14-15 minute initial distribution phase precedes the slower ~2.5-4 hour elimination phase.
Side Effects
Injection Site Reaction
rareMinor irritation, redness, or bruising at the IM/subcutaneous injection site.
Rotate injection sites.
Infusion Reactions (Nausea, Dizziness, Flushing)
uncommonMild nausea, lightheadedness, or flushing can occur during or shortly after IV administration, especially with rapid infusion.
Infuse slowly under supervision; stay hydrated.
Serious Skin Reactions (Stevens-Johnson Syndrome / TEN)
rareThe Philippines FDA (Advisory No. 2019-182) has linked unregulated, high-dose IV glutathione "whitening" injections to rare but life-threatening skin reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis.
Only use pharmaceutical-grade product from a licensed medical provider; avoid unregulated/black-market whitening injections.
Kidney, Liver, or Nervous System Toxicity (Unregulated High-Dose Use)
rareRegulators (e.g. Philippines FDA) have reported toxic effects on the kidneys, liver, and nervous system associated with unregulated, high-dose cosmetic IV glutathione use. Separately, high-dose IV vitamin C, sometimes co-administered for 'synergy', carries its own risks: kidney stones in the general population, and hemolytic anemia specifically in those with G6PD deficiency.
Use only licensed, regulated providers; avoid megadosing; disclose G6PD status before combining with high-dose vitamin C (hemolysis risk).
General Mitigation Strategies
Fundamentally a very safe compound at legitimate, regulated doses. The endogenous antioxidant itself is not toxic. Most reported harms trace back to unregulated, high-dose, or black-market cosmetic IV "whitening" injections rather than the compound itself: use pharmaceutical-grade product from a licensed provider, rotate injection sites, infuse slowly, and avoid stacking with high-dose vitamin C if G6PD-deficient (hemolysis risk).
Post Cycle Therapy (PCT)
Not hormonal. No PCT required.
How It Works
Glutathione is the body's most powerful antioxidant, neutralizing free radicals and supporting Phase II liver detoxification. It recycles other antioxidants (Vitamin C, E) and is essential for cellular health.
Fundamentals
Reference on the practices relevant to Glutathione: how they are done and where they go wrong. Not a recommendation to use it.
Legal Status
Oral glutathione is an OTC dietary supplement (USA); the IV/injectable form is prescription/compounded and not FDA-approved for cosmetic use.
Legal status varies by country and changes over time. This is a general summary, not legal advice.
WADA Status
Glutathione is not listed on the WADA Prohibited List. It is the body's natural antioxidant and is available as a supplement.