What are the benefits of glutathione (glutathione) intravenous (IV) therapy?

Intravenous Glutathione Therapy: Insufficient Evidence for Clinical Benefits

There is no credible evidence supporting the use of intravenous glutathione therapy for any medical indication, and major clinical guidelines recommend against glutamine (a related compound) supplementation in most clinical contexts due to lack of proven benefit and potential harm. 1, 2

Critical Evidence Gaps

Absence of Safety Data for IV Glutathione

• No published studies exist examining the safety of chronic intravenous glutathione administration for any indication. 3
• The only available evidence consists of short-term trials (few doses to 12 weeks maximum) examining IV glutathione for chemotherapy toxicity prevention and Parkinson's disease, with no long-term safety data. 3
• A systematic review specifically addressing IV glutathione for skin lightening found inadequate safety data despite widespread commercial use. 3

Lack of Efficacy Evidence

• No controlled trials demonstrate clinical benefits of IV glutathione on mortality, morbidity, or quality of life outcomes. 3
• One single case report suggested subjective symptom improvement in Parkinson's disease, but this represents the lowest quality of evidence and cannot support clinical recommendations. 4
• While glutathione plays important cellular roles in antioxidant defense, cellular glutathione cannot be effectively increased by administering glutathione itself because it requires extracellular degradation and intracellular resynthesis. 5

Related Compound Evidence: Glutamine

Strong Recommendations Against Use in Critical Illness

• High-dose parenteral glutamine is contraindicated in critically ill patients with organ dysfunction, as it has been associated with increased mortality. 1, 2, 6
• The REDOX trial demonstrated that high-dose intravenous glutamine was harmful in critically ill patients with kidney failure. 1

Cancer Patients

• ESPEN guidelines state there is insufficient evidence to recommend glutamine supplementation in cancer patients undergoing chemotherapy, radiotherapy, or targeted therapy. 1, 2
• Concerns exist about glutamine potentially fueling cancer cell metabolism. 2
• No consistent benefit demonstrated for radiation-induced diarrhea, mucositis, or skin toxicity. 1

Limited Appropriate Use

• Parenteral glutamine (0.5 g/kg/day) may only be considered in patients requiring exclusive parenteral nutrition who cannot be fed enterally, though this is a weak recommendation. 2, 6

Specific Safety Concerns for IV Glutathione

Potential Harms

• Switching from brown to red melanin production may increase the risk of sun-induced skin cancers in previously protected individuals when used for skin lightening. 3
• Complications from IV infusions themselves present additional risks. 3
• No regulatory assessment exists for systemic glutathione administration for cosmetic or therapeutic use. 3

Clinical Bottom Line

• IV glutathione therapy lacks evidence for any clinical benefit on meaningful outcomes (mortality, morbidity, quality of life). 2, 3
• No safety data exists for chronic administration. 3
• The biological rationale (antioxidant effects) does not translate to clinical efficacy, as exogenous glutathione administration does not effectively increase intracellular levels. 5
• Related compounds like glutamine have shown potential harm in specific populations, raising concerns about similar interventions. 1

Regulatory assessment and rigorous clinical trials are urgently needed before IV glutathione can be recommended for any indication. 3