What is glutathione used for?

What Glutathione Is Used For

Glutathione is primarily used clinically as a precursor for antioxidant defense systems, with established indications including parenteral glutamine (glutathione precursor) supplementation in hematopoietic stem cell transplant patients and burn victims, prevention of chemotherapy-induced neurotoxicity from platinum agents, and as a component in certain topical skin formulations—though its widespread use for cosmetic skin lightening lacks adequate safety data and regulatory approval. 1, 2, 3

Established Clinical Applications

Critical Care and Nutritional Support

• Glutamine supplementation (which serves as a glutathione precursor) is recommended at 0.3-0.5 g/kg/day for burn patients with >20% body surface area involvement for 10-15 days 1, 3
• For critically ill trauma patients with complicated wound healing, glutamine 0.2-0.3 g/kg/day can be administered 1, 3
• The American Society for Parenteral and Enteral Nutrition recommends parenteral glutamine at approximately 0.6 g/kg/day for hematopoietic stem cell transplant patients to minimize intestinal mucosal atrophy and potentially reduce infection risk 2

Chemotherapy-Related Neuropathy Prevention

• Six small randomized trials evaluated glutathione against platinum-based neurotoxicity, with five showing statistically significant reductions in neuropathy incidence and severity, improvements in nerve conduction, and quality of life 3
• N-acetylcysteine (which increases serum glutathione) at 1,200 mg orally reduced grade 2-4 sensory neuropathy in oxaliplatin-treated colon cancer patients (20% vs 89% in placebo, P<0.05) 3
• Important caveat: A larger placebo-controlled trial found glutathione ineffective for preventing taxane-induced neuropathy in 185 patients receiving paclitaxel/carboplatin, suggesting it may not work for all chemotherapy types 3

Physiological Roles

Antioxidant and Metabolic Functions

• Glutathione serves as "the master antioxidant," participating in cellular redox reactions and protecting against reactive oxygen, nitrogen, and sulfur species 4, 5
• Glutathione peroxidase 4 (GPX4) plays a major role in inhibiting lipid peroxidation and preventing ferroptosis (regulated cell death) 1
• It participates in detoxifying xenobiotics, protecting protein thiols, regulating the cell cycle, and storing cysteine 5

Cosmetic Applications (Controversial)

Skin Lightening Claims

• Glutathione is heavily marketed for skin lightening in Asia and internationally, but this use lacks adequate safety data and regulatory approval 6, 7
• Limited evidence exists: oral glutathione 500 mg/day and topical 2% oxidized glutathione showed some brightening in sun-exposed areas measured by melanin index, but results were inconsistent 8
• Critical safety concern: The switch from brown to red melanin production may increase risk of sun-induced skin cancers in previously protected individuals 6
• The FDA-approved topical formulation contains only 1% glutathione combined with other ingredients (ascorbic acid, niacinamide, kojic acid) 9

Important Contraindications and Warnings

When NOT to Use

• High-dose parenteral glutamine should NOT be administered to patients with acute kidney injury, chronic kidney disease with kidney failure, or unstable ICU patients with liver and renal failure 2, 3
• The Society of Critical Care Medicine reports that high-dose glutamine supplementation is associated with increased mortality in critically ill patients with multi-organ failure 2
• Glutamine supplementation is NOT recommended for general ICU patients except those with burns or trauma 3, 1
• The Cystic Fibrosis Foundation states there are no data supporting glutathione therapy for cystic fibrosis patients 2

Clinical Measurement

• Whole blood selenium measurement provides insight into glutathione peroxidase activity, as selenium is an essential component of these enzymes 1
• Glutathione imbalance is observed in tuberculosis, HIV, diabetes, cancer, and aging, making it a potential biomarker for disease states 4

Common Pitfalls to Avoid

• Avoid intravenous glutathione for cosmetic skin lightening: No long-term safety studies exist for chronic IV use, and regulatory assessment is urgently needed 6, 7
• Do not use in multi-organ failure: Despite glutathione's theoretical benefits, high-dose supplementation increases mortality in this population 2
• Recognize limited oral bioavailability: Clinical efficacy of oral glutathione is questionable due to limited absorption, with effects being reversible 8, 7