WhatPeptide

Glutathione

Glutathione is the body's master endogenous antioxidant, a tripeptide that plays a central role in detoxification, immune function, and reduction of oxidative stress. Exogenous supplementation via injection or infusion is studied for supporting antioxidant status in contexts of chronic illness, aging, and metabolic stress.

Moderate evidence Unregulated Antioxidant

Written by WhatPeptide Editorial Team · Last updated 2026-03-17

Tripeptide antioxidant, typically classified as a supplement rather than therapeutic peptide.

Half-life

Approximately 10 minutes in plasma; intracellular half-life longer

Dosage range

200-1400 mg subcutaneously or IV 2-3 times weekly (clinical literature context)

Administration

Subcutaneous injection

Research level

Moderate

How Glutathione works

Glutathione directly neutralizes reactive oxygen species and reactive nitrogen species, and serves as the essential cofactor for glutathione peroxidases and glutathione S-transferases that conjugate toxins and peroxides for elimination. Systemic administration increases intracellular GSH levels in lymphocytes and other tissues, supporting cellular redox homeostasis. Intravenous and subcutaneous routes bypass the poor oral bioavailability caused by intestinal peptidase degradation.

Also known as: GSH, Gamma-glutamylcysteinylglycine, Reduced glutathione

Research relevance

Immune Support
Moderate relevance 55
Anti-Aging & Longevity
Some relevance 40

Side effects & safety

Injection site discomfort Potential zinc depletion with prolonged use Rare allergic reactions

Contraindications

Asthma (inhaled form)
Known hypersensitivity

Consult a healthcare provider before use if any of these apply to you.

Key studies

FAQ

What is Glutathione? +
Glutathione is the body's master endogenous antioxidant, a tripeptide that plays a central role in detoxification, immune function, and reduction of oxidative stress. Exogenous supplementation via injection or infusion is studied for supporting antioxidant status in contexts of chronic illness, aging, and metabolic stress. Its mechanism of action is supported by moderate clinical and preclinical evidence.
What is Glutathione researched for? +
Glutathione has the strongest research relevance for Immune Support, Anti-Aging & Longevity. Evidence is supported by moderate clinical and preclinical evidence.
What are the side effects of Glutathione? +
Reported side effects include Injection site discomfort, Potential zinc depletion with prolonged use, Rare allergic reactions. Key contraindications: Asthma (inhaled form); Known hypersensitivity.
Is Glutathione FDA approved? +
Glutathione is not FDA-approved. It is available as a research compound or through compounding pharmacies in some jurisdictions.
How is Glutathione administered? +
Glutathione is typically administered via subcutaneous route. Researched dosage range: 200-1400 mg subcutaneously or IV 2-3 times weekly (clinical literature context). Half-life: Approximately 10 minutes in plasma; intracellular half-life longer.

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