The short version

Plain English first. Everything below this section is the same material with the sources, the numbers and the caveats attached.

What glutathione is

A tripeptide — glutamate, cysteine, glycine — and the principal redox buffer of every cell in your body. It is one of the best-characterised molecules in biochemistry. Nothing on this page disputes that. The entire question is whether putting more of it in a syringe does anything.

The gamma bond, which explains most of what follows

In an ordinary peptide, one residue joins the next through the backbone carboxyl. In glutathione the glutamate is joined through the carboxyl on its side chain instead — a gamma linkage rather than an alpha one. Three things follow, and they are the spine of this page.

• Ordinary proteases cannot touch it. They recognise alpha linkages. The gamma bond is invisible to them. That is why a three amino acid peptide can circulate and function at millimolar concentration without being immediately dismantled.
• One enzyme can, and it sits exactly where it does the most damage. Gamma-glutamyl transpeptidase is the dedicated enzyme for that bond, and it lines the small intestine and the liver — the two tissues a swallowed dose has to cross.
• It cannot be made on a ribosome. Because the bond is not an alpha bond, the translation machinery cannot build it. Two ATP-dependent enzymes assemble it instead, and the rate-limiting input is cysteine. That is why the clinically established drug in this space is N-acetylcysteine, not glutathione.

A short way to put it: the gamma bond is why proteases leave glutathione alone, and gamma-glutamyl transpeptidase is why your gut does not.

Reduced and oxidised are not the same molecule

Glutathione's cysteine carries a free thiol. Two of them oxidise to a disulfide — GSSG. In healthy tissue more than 90% of the pool is the reduced form, and the ratio between them, not the absolute level, is the meaningful readout.

What a 600 mg vial represents, numerically

Reduced glutathione is normally supplied as the free acid rather than a salt, which spares it the counterion arithmetic that afflicts synthetic peptides. That is a genuine point in its favour. The numbers that matter here are different ones:

• 600 mg is 1.95 mmol. Reconstituted in 10 mL that is 195 mmol/L — twenty to a hundred times the concentration inside a healthy cell, and something like ten thousand times normal extracellular fluid.
• Measured baseline plasma glutathione is about 6.2 µmol/L. Across a whole plasma volume that is roughly 6 mg. A 600 mg dose is on the order of a hundred times the entire circulating plasma pool, delivered at once, and then cleared with a fourteen-minute half-life.

Ours is the arithmetic; the concentrations and the half-life are published. Stated that way, the mismatch is the most honest thing that can be said about intravenous glutathione.

How it works

The biochemistry is not controversial and the sceptical position here is emphatically not “glutathione does nothing.” It is the principal intracellular redox buffer, the electron donor for the glutathione peroxidases, and the conjugating partner in phase II detoxification. All established.

The transporter problem, which is the crux of the whole compound

This has been tested directly, and the cleanest demonstration is a 2016 paper whose title says the whole thing: the glutathione derivative GSH monoethyl ester may effectively whiten skin but GSH does not. An esterified version that can cross a membrane worked. The free tripeptide did not. The same logic runs through the older radioprotection work with glutathione esters, and through the Parkinson's literature, where the commentary is blunt: exogenous glutathione “cannot be taken up by neurons,” while N-acetylcysteine is.

So the mechanistic line is: glutathione is a molecule cells make, not a molecule cells absorb. Delivering more of it to the outside of a cell is not obviously the same intervention as having more of it inside.

The depigmentation mechanism, and the uncomfortable part of it

For skin lightening specifically the proposed mechanism is coherent — which is what makes the missing clinical evidence so striking. Four routes are described: direct inhibition of tyrosinase by chelating its copper site; interference with the transfer of tyrosinase to premelanosomes; indirect antioxidant blocking of peroxide-induced tyrosinase activity; and a switch in melanin production from eumelanin toward pheomelanin.

Pharmacokinetics

This is the best-documented part of the whole subject and it is almost never cited by anyone selling the vial. Real human data exists, for both routes.

Oral, the classic negative

Seven healthy volunteers, about 3 g by mouth, plasma sampled for 270 minutes. Glutathione, cysteine and glutamate concentrations “did not increase significantly.” The conclusion, verbatim: “the systemic availability of glutathione is negligible in man.” The stated mechanism is gamma-glutamyl transpeptidase in the gut wall and liver.

Two honest caveats about the study everybody cites and almost nobody reads. It is a single dose over four and a half hours in seven people. It shows one dose does not acutely raise plasma glutathione. It does not show that chronic dosing cannot raise tissue stores — a different question, answered differently below.

Oral, the positive one

A six-month randomised double-blind placebo-controlled trial in 54 adults at 250 and 1,000 mg a day found glutathione up 30 to 35% in red cells, plasma and lymphocytes at the high dose, up 17 to 29% at the low dose, with the oxidised-to-reduced ratio falling and natural killer cell cytotoxicity more than doubling at three months. Levels returned toward baseline within a month of stopping.

That is a good study and we are not going to pretend otherwise. Three fair observations: it measures stores, not clinical outcomes; it does not contradict the 1992 negative, because the two asked different questions; and the most likely explanation is that the constituent amino acids are what get absorbed and reassembled, not the intact tripeptide.

Intravenous, where the interesting number is

Work that through for a 600 mg dose, assuming ordinary first-order elimination:

The half-life figure comes from a 1991 paper the publisher would not let us open. We have it quoted, with a full citation, from a review published by a company selling oral glutathione — a source with no incentive to make the intravenous route look bad, which slightly raises our confidence rather than lowering it. It should still be checked against the primary.

What the evidence shows

Glutathione has been through real randomised trials in three settings. In the one it is actually sold for, there is a single controlled study and it was negative.

Skin lightening, which is what this vial is bought for

One placebo-controlled trial of the injection exists: 25 patients, 1,200 mg intravenously twice weekly for six weeks, against saline. Its conclusion was that intravenous glutathione “was not found to be an effective or long-lasting treatment for skin tone lightening.”

What the leading reviewers say about the state of that evidence is worth quoting directly:

Meanwhile the positive trials exist — for other routes.

Note what the topical work actually uses: oxidised glutathione, S-acyl glutathione, a modified membrane-permeant derivative, or an amino-acid precursor blend. It does not use plain reduced GSH. That is the transporter finding again, arriving from a different direction.

Parkinson's disease — the clearest arc in the literature

Glutathione depletion in the substantia nigra is one of the oldest observations in Parkinson's pathology, so this is a mechanistically motivated programme, not a fringe one. Watch what happens when controls arrive.

The 2017 trial is the instructive one. The high-dose group genuinely improved, by 4.6 points on the total rating scale. The placebo group improved by 3.4. That is what an open-label result looks like once you put a control group next to it.

Note the dose in the 1996 study: 600 mg — the same as this vial, twice a day, under supervision, for a serious neurodegenerative disease.

Chemotherapy neuropathy — the approved indication, and where it ran out

This matters because the only approved injectable indication we could verify anywhere is chemotherapy adjunct. Several small randomised trials in the 1990s and 2000s reported protection against platinum-induced nerve damage. Then a phase 3 arrived: 185 patients, 1.5 g/m² intravenously before each chemotherapy dose, randomised double-blind placebo-controlled.

The comparison that makes the whole case

The clinically established way to raise glutathione is an approved oral drug that costs very little and does not require a needle. The injection is the unapproved route to the same endpoint, and it is the more expensive one.

Reconstitution

This section contains the two most practically useful facts on the page, and neither of them appears on any competitor page we read.

Volume — 600 mg will not go into 2 mL

Two analytical suppliers agree exactly at 20 mg/mL; a database says 50. We have not resolved the disagreement and would work from the concordant figure.

This also tells you something about what the vial is: a product needing 12 to 30 mL is an intravenous push or drip product, not a subcutaneous one. Either that, or pharmaceutical preparations are pH-adjusted or supplied as a sodium salt, both of which raise aqueous solubility considerably. We could not obtain product documentation for any approved injectable glutathione anywhere, so we cannot tell you which.

pH — the thing nobody mentions

Glutathione has two carboxylic acids, with pK_a values of 2.12 and 3.53. It is an acid, and its solutions are acidic. The measured figure is pH 3 for a 1% solution. A 600 mg vial in 10 mL is six times more concentrated than that, so more acidic still.

We are not going to compute a pH figure for a reconstituted vial — at that concentration a naive calculation is unreliable and this page does not invent numbers. The direction is unambiguous and the measured 1% figure is enough to make the point.

Oxidation, and a trade-off worth knowing

Reduced glutathione oxidises to GSSG spontaneously in aerated water, accelerated by trace metals, by warmth, and by rising pH. That last one produces a genuine tension: the acidity that hurts on injection is the same acidity that protects the molecule from oxidising. Neutralise the solution and you make it kinder to a vein and less stable in the vial.

We searched specifically for a quantitative stability study of reconstituted glutathione — any “X% remains after Y days at Z degrees” figure — and found none. The 28-day bacteriostatic water convention our storage guide gives for peptides has no evidential basis for this compound, and given documented ready oxidation, the defensible position is to treat reconstituted glutathione as less stable than a typical peptide, not more. Minimise headspace time and repeated needle entries: each one introduces oxygen to a solution of a compound whose defining property is that it reacts with oxidants.

Reported protocols

The leading review's phrase for what circulates is exact: “arbitrary dosage schedules, despite complete lack of evidence.”

Note where a 600 mg vial sits: at the bottom of the circulating intravenous range. Someone following the commonly quoted 1,200 mg protocol is using two vials per session.

How the cosmetic doses compare with the clinical ones

There is no sense in which the cosmetic use is a low-dose or gentle application. The doses sit in the same range as those used in oncology and neurology trials, and the 1,200 mg twice-weekly protocol is above the dose given in the Parkinson's study.

One unpublished practitioner observation, recorded in the leading review, describes the actual clinical course rather than the marketed one: hypopigmented patches on sun-exposed areas after ten to twelve injections, resolving only after thirty to forty as the effect evens out. The review flags it as unpublished. We repeat it because it is a very different picture from the advertising, and because it is sourced to the best review in the field rather than to a clinic blog.

Storage

Our storage guide covers the general conventions, with two adjustments for this compound.

Suppliers disagree about the solid: one analytical supplier says −20 °C, two others say 2 to 8 °C. None recommends ambient. For a compound that oxidises readily the colder recommendation is the conservative one.

• Some glutathione material is hygroscopic — it pulls in atmospheric moisture. A lyophilisate that has taken up water has begun to hydrate, and hydrated glutathione oxidises faster than dry. Keep the vial sealed and let it reach room temperature before opening, so condensation does not form on cold powder.
• Purity grades run from 95% to 99.99% across the commercial market, which is a very wide range and maps directly onto price. A vial is not simply glutathione or not glutathione; it is glutathione at some grade, and the grade belongs on the certificate.

On light: we looked specifically at four supplier datasheets and none of them stated a light-sensitivity warning, so we are not going to assert one. What is defensible is that photochemistry accelerates thiol oxidation generally, and that amber vialling and carton storage are prudent for an oxidisable compound. Good practice, not a documented requirement.

For the reconstituted solution there is no published stability figure we could find. See the reconstitution section: do not extend the peptide convention here by analogy.

Reported effects

The most important safety document about glutathione is not about glutathione. It is about what was in the powder.

The 2019 FDA compounding alert

Note what did not go wrong. The molecule was correct. The dose was ordinary. The patients were in a professional setting. What went wrong is that food-grade powder went into a syringe — which is a precise description of what a lyophilised research-grade glutathione vial is.

What has been reported from cosmetic use

The Philippine Dermatological Society has documented 69 cases of adverse events from intravenous glutathione, including renal failure, endocrine disorders, severe allergic reactions, liver toxicity, anaphylaxis, Stevens-Johnson syndrome, blood clots and neurological symptoms. The society has held a position against cosmetic glutathione since 2008.

The published reviews consistently list: Stevens-Johnson syndrome and toxic epidermal necrolysis, kidney dysfunction, liver dysfunction, thyroid dysfunction, severe abdominal pain — and “air embolism or potentially fatal sepsis due to incorrect sterile method.”

Preserve the framing of that last item. Air embolism and sepsis are not pharmacological effects of glutathione. They are consequences of putting a needle in a vein badly, in a salon, repeatedly. Which makes them more relevant to a self-administered research vial, not less.

Two case reports worth naming precisely

• Stevens-Johnson syndrome, 2025. A peer-reviewed case of SJS/toxic epidermal necrolysis “potentially triggered by an intravenous vitamin infusion containing glutathione, vitamin C, and vitamin D administered at a wellness center.” Two things must be said. The infusion contained three substances and the authors themselves say “potentially” — glutathione is not established as the culprit. And it is a real, indexed case of a life-threatening emergency after a cosmetic drip, which is exactly the use pattern this product is sold into. We could not open the full text and have no patient details, dose or outcome.
• Toxic epidermal necrolysis from oral whitening pills, 2021. Notable for its title alone: causality was confirmed by immunospot assay and mass spectrometry — not an association, but a case where the laboratory work was done to attribute the reaction. And it was the oral route, which is a useful corrective to any assumption that swallowing it is inert because it absorbs poorly. We could not open it; we have the title and nothing more.

The honest summary

That is a more nuanced picture than “glutathione is dangerous,” and it is the accurate one. The risk here is overwhelmingly a route, sterility and supply-chain risk. Which, for an unregulated vial reconstituted at a kitchen table, is not reassuring at all.

Two figures circulate that we will not repeat as fact. A clinic page claims “37.5% saw benefit, 32% had adverse events” from the one intravenous trial, with no citation of any kind. Another attributes to “a 2025 narrative review” the claim that almost a third of patients developed liver failure — which is not credible as stated, since a one-in-three rate of liver failure from a cosmetic procedure would be a public health emergency rather than a footnote. Both are recorded here only so they can be recognised when they turn up elsewhere.

Regulatory status

Glutathione does not fit the template. Most compounds in this library are unapproved everywhere and named on watch-lists. Glutathione is approved as an injectable medicine in at least one country, sold as a food supplement in most, on no peptide watch-list we could find, and the subject of a dedicated FDA safety communication about sterile compounding. All four at once.

The Philippines — where this fight actually happened

The largest market in the world for cosmetic glutathione, and the jurisdiction with the clearest position. From the FDA advisory, verbatim:

The harms it names: toxic effects on the liver, kidneys and nervous system; Stevens-Johnson syndrome; kidney stones when combined with intravenous vitamin C; theoretical long-term skin cancer risk; and transmission of HIV and hepatitis B and C.

The position has hardened rather than softened. In February 2024 the Department of Health restated all of it and added the operational point — there are “no guidelines for appropriate dosing regimens and duration of treatment.” The Health Secretary was blunter: “It is not safe. The FDA has not registered it for skin whitening. If there's someone using it, it is illegal.”

United States

Injectable glutathione is not an FDA-approved drug. Oral glutathione is a lawful dietary ingredient. That dual status is the entire problem, and FDA said so: its 2019 finding was not that glutathione is dangerous but that the ingredient being injected had been manufactured for food.

A checked negative worth stating positively: glutathione does not appear on FDA's Category 2 list of bulk substances presenting significant safety risks — the list that does name GHRP-2, GHRP-6, kisspeptin-10 and ipamorelin acetate. We checked both that table and the “nominated but withdrawn” table. It is on neither.

A legal analysis describes glutathione as sitting under enforcement discretion for compounding in limited settings, not compoundable for general office stock. We could not verify that against FDA's own published tables and are reporting it as a law firm's summary rather than as established.

Canada

We checked both advisories individually. Health Canada's 9 April 2026 advisory names fourteen products. Glutathione is not among them. The 1 August 2025 Canada Peptide seizure advisory names forty-four. Glutathione is not among those either.

Oral glutathione is very likely regulated in Canada as a natural health product with a product number, while an injectable would be a drug requiring market authorisation — a distinction that matters enormously, because it is the difference between a lawful capsule and an unauthorised injection of the same molecule. We could not verify it; the licensed natural health products database was not reachable, and we are not going to state Canada's position on the oral form without checking it.

Sport

We could not open the current prohibited list and found no source placing glutathione on it. Our reasoning — and it is reasoning, not a citation — is that it is probably not prohibited, for an interesting reason. The catch-all class that captures most of this library covers substances with no approval by any government health authority for human therapeutic use. Glutathione has one: the Philippines approves the injection as a chemotherapy adjunct. It is also a normal constituent of food.

Treat that as our inference until checked. And note the irony — the fact that makes glutathione unusual in this catalogue is that somebody's medicines regulator actually approved it for something.

Australia

Not established. We reached no source at all. We are recording that as a plain gap rather than reasoning about it.

Sentient Biogenix supplies glutathione for laboratory research use only. It is not for human or veterinary use.

Questions we actually get

Does injected glutathione whiten skin?

The one placebo-controlled trial — 25 patients, 1,200 mg twice weekly for six weeks — concluded that it did not. The leading review says of intravenous glutathione for skin lightening that “there is not even a single clinical trial evaluating its efficacy.” The Philippines FDA says the same and has approved no injectable product for the purpose. The evidence that does exist is for oral glutathione at 500 mg a day, and for topical oxidised glutathione at 2% — a different route and, in the topical case, a different molecule.

Doesn't IV bypass the poor oral absorption?

Yes, and then it runs into the next problem. A 2 g intravenous dose has a plasma half-life of about fourteen minutes, with excretion up roughly three hundredfold within ninety. Bypassing first-pass metabolism is a real pharmacological statement that here buys you about two hours. And it does not touch the deeper issue: there is no membrane transporter to carry finished glutathione into a cell.

Why does it sting?

Because it is an acid. Two carboxyl groups, and a 1% solution measures pH 3. A 600 mg vial in 10 mL is six times more concentrated than that. Approved parenteral products manage it with pH adjustment and a matched diluent. A plain lyophilised vial reconstituted in bacteriostatic water has neither.

How much water does 600 mg actually need?

About 30 mL at the solubility figure two analytical suppliers agree on, or about 12 mL at the most generous figure we found. Not 2 mL. If you are told to put it in a peptide-sized volume and it does not fully dissolve, the instruction was wrong, not the vial.

Isn't 99% purity enough?

Not for this compound, and this is the one thing worth taking away from the page. FDA's 2019 finding was endotoxin, not chemical purity. Endotoxin is bacterial cell-wall debris, it is not what an HPLC purity assay measures, and it is heat-stable so it survives sterilisation. A chemically pure vial can carry a dangerous endotoxin load. Ask for a bacterial endotoxin test result in endotoxin units per milligram.

What's the difference between GSH and GSSG?

GSH is reduced glutathione with a free thiol; GSSG is two of them joined by a disulfide. Over 90% of the pool in healthy tissue is reduced. GSH oxidises to GSSG readily in air and in solution, so a vial labelled “reduced” becomes progressively less so once opened and dissolved. Note the irony: the best-evidenced topical whitening formulation is GSSG.

So is oral glutathione useless?

No, and the 1992 study everyone cites for that does not say so. It shows a single 3 g dose does not acutely raise plasma glutathione. A six-month randomised trial at 250 to 1,000 mg a day found tissue glutathione up 17 to 35% depending on dose and compartment. The likely explanation is that the constituent amino acids are what get absorbed and reassembled — which is also why the established drug in this space is N-acetylcysteine.

Is it banned in sport?

We could not open the current list and found no source placing it on one. Our reasoning is that it probably is not, because the catch-all class covers substances with no approval by any government health authority, and glutathione has one. Treat that as our inference until checked.

What is the real risk?

Not, on the available evidence, the molecule. Oral trials at a gram a day for six months and a 185-patient phase 3 at high intravenous doses found no meaningful toxicity signal. The documented harms are about the needle, the setting and the grade of the powder: endotoxin at five times the limit, seven patients affected and one hospitalised; air embolism and sepsis from incorrect sterile method; a regulator warning about HIV and hepatitis transmission. Those are the risks of injecting a food ingredient outside a pharmacy, and they do not go away because the molecule is one your body already makes.

References

1. US Food and Drug Administration. FDA highlights concerns with using the dietary ingredient glutathione to compound sterile injectables. 7 June 2019. fda.gov — the most important document on this page. The seven patients, the hospitalisation, the endotoxin finding and the manufacturer's statement. Read in full.
2. Philippines Food and Drug Administration. Advisory No. 2019-182: unsafe use of glutathione as skin lightening agent. fda.gov.ph — the approved indication, the absence of trials, and the harms named. Read in full.
3. Sonthalia S, Daulatabad D, Sarkar R. Glutathione as a skin whitening agent: facts, myths, evidence and controversies. Indian Journal of Dermatology, Venereology and Leprology 2016;82(3):262–272. PMID 27088927. ijdvl.com — the standard review. The depigmentation mechanisms, the “arbitrary dosage schedules” line, and the practitioner observation about hypopigmented patches.
4. Witschi A, Reddy S, Stofer B, Lauterburg BH. The systemic availability of oral glutathione. European Journal of Clinical Pharmacology 1992;43(6):667–669. DOI 10.1007/BF02284971. link.springer.com — the classic oral negative, and the gamma-glutamyl transpeptidase explanation.
5. Aebi S, Assereto R, Lauterburg BH. High-dose intravenous glutathione in man: pharmacokinetics and effects on cyst(e)ine in plasma and urine. European Journal of Clinical Investigation 1991;21(1):103–110. DOI 10.1111/j.1365-2362.1991.tb01366.x. — the source of the 14.1 ± 9.2 minute half-life. The publisher would not let us open it; the figure is quoted, with full citation, from a review published by an oral glutathione company.
6. Richie JP Jr, Nichenametla S, Neidig W, et al. Randomized controlled trial of oral glutathione supplementation on body stores of glutathione. European Journal of Nutrition 2015;54(2):251–263. DOI 10.1007/s00394-014-0706-z. PMID 24791752. link.springer.com — the six-month oral positive.
7. Leal AD, Qin R, Atherton PJ, et al. NCCTG/Alliance trial N08CA: the use of glutathione for prevention of paclitaxel/carboplatin-induced peripheral neuropathy — a phase 3 randomized, double-blind, placebo-controlled study. Cancer 2014;120(12):1890–1897. DOI 10.1002/cncr.28654. acsjournals.onlinelibrary.wiley.com — 185 patients; the null primary and the two secondary endpoints that favoured placebo.
8. Mischley LK, Lau RC, Shankland EG, Wilbur TK, Padowski JM. Phase IIb study of intranasal glutathione in Parkinson's disease. Journal of Parkinson's Disease 2017;7(2):289–299. DOI 10.3233/JPD-161040. PMID 28436395. journals.sagepub.com — 45 patients; the drug arm improved, and so did placebo.
9. Hauser RA, Lyons KE, McClain T, Carter S, Perlmutter D. Randomized, double-blind, pilot evaluation of intravenous glutathione in Parkinson's disease. Movement Disorders 2009;24(7):979–983. DOI 10.1002/mds.22401. PMID 19230029. — the 20-patient randomised negative. Publisher returned an error; design and result via two concordant secondary accounts.
10. Zubair S, Hafeez S, Mujtaba G. Efficacy of intravenous glutathione vs. placebo for skin tone lightening. Journal of the Pakistan Association of Dermatologists 2016;26(3):177–181. — the only controlled trial of the injection for skin lightening. We could not open the primary; the design and the negative conclusion are attested by two independent published reviews that agree on every particular.
11. Watanabe F, Hashizume E, Chan GP, Kamimura A. Skin-whitening and skin-condition-improving effects of topical oxidized glutathione. Clinical, Cosmetic and Investigational Dermatology 2014;7:267–274. PMID 25125999. — the 2% GSSG split-face trial. The best-evidenced formulation in the whole subject, and it is topical, and it is the oxidised molecule.
12. Oncology Nursing Society. Glutathione for peripheral neuropathy — “Effectiveness Not Established.” ons.org
13. Health Canada. Think twice before injecting peptides bought online. Public advisory, 9 April 2026. recalls-rappels.canada.ca — fourteen products; glutathione is not among them. Also the source of the research-use-only labelling statement.
14. Health Canada. Unauthorized injectable peptide drugs seized and sold by Canada Peptide. Advisory, 1 August 2025. recalls-rappels.canada.ca — forty-four products; glutathione is not among them either.
15. Intravenous glutathione and vitamin supplementation causing Stevens-Johnson syndrome: a case report. Journal of Burn Care and Research 2025;46(3):652. DOI 10.1093/jbcr/iraf027. PMID 40057759. — we could not open the full text. We have the abstract's own framing and nothing more.

Listed rather than hidden, what we could not check. The 1991 intravenous pharmacokinetic paper, the only controlled intravenous whitening trial, the 2009 Parkinson's trial and the 1990s chemotherapy trials were all behind publisher blocks; their designs and results come from concordant secondary accounts and citations we verified. We could not read either of the two case reports of severe skin reactions, and we have no patient details for them. We could not obtain the founding 2011 Philippines advisory, only the 2019 one that superseded it. We could not obtain a manufacturer's specification for any approved injectable glutathione product anywhere, which is why this page states nothing about their pH, excipients, salt form or diluent. We found no quantitative stability study of glutathione in solution — an absence of published data, not a negative finding. Health Canada's natural health product position on oral glutathione is unverified. We reached no Australian source at all. And the anti-doping reasoning is entirely ours: we did not open the current prohibited list.