Limited evidenceJoints & skin

Skin Brightening Formulas

Oral glutathione, usually with vitamin C and other antioxidants, marketed for a lighter or more even complexion. Small trials do show a measurable drop in skin melanin index, but the studies are short, of mixed quality, and the effect fades when you stop.

Evidence last reviewed: August 2026

What the science says

Reduced melanin index Limited evidence
A systematic review identified five randomized controlled trials and one open study of oral glutathione at 250 mg once or twice daily or 500 mg daily, all reporting a significant reduction in melanin index versus placebo. Roughly half the studies carried a high risk of bias, and the reviewers described the outcomes as moderately effective but unsustainable.
Combining oral and topical forms Limited evidence
A double-blind randomized trial found that topical 2% glutathione plus oral glutathione lowered melanin index more than either alone, in a small sample over a few weeks. Longer-term skin tone outcomes were not measured.
Injectable glutathione Limited evidence
The same review found only one placebo-controlled study of intravenous glutathione, with no clear efficacy, and concluded that the intravenous route is contraindicated because of its side-effect profile.

Dosage & safety

Studied doseTrial doses were 250–500 mg oral glutathione per day for 4–12 weeks, often with 500–1000 mg vitamin C. There is no established long-term dose.

SafetyOral glutathione is poorly absorbed and generally well tolerated at these doses. Injected or intravenous glutathione for skin lightening has been linked to serious adverse events and is not recommended by dermatology reviews or by several national regulators. Lightening does not protect against sun damage — daily sunscreen matters far more for pigmentation than any capsule. New or changing pigmented patches should be assessed by a doctor.

Scientific references

Glutathione as a skin-lightening agent and in melasma: a systematic review
Sarkar R, Yadav V, Yadav T, P J, Mandal I — Int J Dermatol, 2025
Combination of topical and oral glutathione as a skin-whitening agent: a double-blind randomized controlled clinical trial
Wahab S, Anwar AI, Zainuddin AN, Hutabarat EN, Anwar AA, Kurniadi I — Int J Dermatol, 2021

Where to buy

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