Maximum Dose of Glutathione
The maximum recommended dose of glutathione is 1500-2500 mg per day for intravenous administration, while oral glutathione supplementation has been studied at doses ranging from 250-1000 mg per day with demonstrated safety. 1
Dosage Guidelines by Administration Route
Intravenous Administration
- Standard dosing range: 1500-2500 mg per IV administration 1
- Specific protocols used in clinical studies:
Oral Administration
- Studied effective doses: 250-1000 mg/day 3
- Low dose: 250 mg/day
- High dose: 1000 mg/day
- Both doses showed significant increases in blood glutathione levels after 6 months
- NAFLD treatment: 300 mg/day has been studied with positive results 4
- Skin lightening combination: 250 mg glutathione combined with 500 mg L-cystine daily 5
Subcutaneous Administration
- Typical range: 600-1500 mg per administration 1
- Note: There are no standardized guidelines specifically for subcutaneous glutathione use
Safety Considerations
- Glutathione is generally well-tolerated but may cause skin rash, headache, and gastrointestinal discomfort 1
- Testing for G6PD deficiency should be considered before administration, as glutathione may potentially cause similar concerns as other reducing agents 2, 1
- In a 6-month randomized controlled trial, doses up to 1000 mg/day oral glutathione were well-tolerated with no significant adverse effects 3
- Long-term safety data for regular subcutaneous administration is lacking 1
Clinical Evidence for Efficacy
- A randomized controlled trial showed that oral glutathione at 250-1000 mg/day increased glutathione levels in blood by 30-35% in erythrocytes, plasma, and lymphocytes after 6 months of supplementation 3
- In chemotherapy settings, higher doses (1500-2500 mg) have been studied for prevention of chemotherapy-induced neuropathy 2
- For NAFLD, a dose of 300 mg/day for 4 months showed significant decreases in ALT levels and other markers of liver function 4
Special Populations
- In older adults with high oxidative stress, supplementation with glycine and N-acetylcysteine (precursors to glutathione) at doses of 4.8-7.2 g/day may increase glutathione levels 6
- Caution is advised for IV glutathione use for cosmetic purposes (skin lightening) due to limited safety data for chronic use 7
While glutathione has been studied at various doses for different conditions, the evidence suggests that intravenous doses should generally not exceed 2500 mg per administration, and oral supplementation is typically safe at doses up to 1000 mg daily. Always consider the specific clinical context and administration route when determining appropriate dosing.