Glutathione and Glutamine in Clinical Practice

Parenteral Glutamine Recommendations

The American Society for Parenteral and Enteral Nutrition recommends parenteral glutamine at approximately 0.6 g/kg/day for Hematopoietic Stem Cell Transplantation (HSCT) patients 1
ESPEN guidelines state there are insufficient consistent clinical data to recommend glutamine to improve clinical outcomes in high-dose chemotherapy and HSCT 2, 3
One RCT showed more severe oral mucositis and increased relapses with glutamine supplementation in HSCT 4
Parenteral glutamine (0.35-0.5 g/kg/day) may be considered only for surgical patients who cannot be fed enterally and require exclusive PN, but this is a weak recommendation due to mixed evidence 5, 6, 1
The Society of Critical Care Medicine reports increased mortality with high-dose glutamine in critically ill patients with multi-organ failure 1
The National Kidney Foundation recommends against high-dose parenteral glutamine in acute kidney injury or chronic kidney disease with kidney failure 1

ESPEN states there is insufficient evidence to recommend glutamine supplementation during conventional cytotoxic therapy, targeted therapy, or radiotherapy 2, 8, 4
The Cystic Fibrosis Foundation states there are no data supporting glutathione therapy for cystic fibrosis patients 1

Do not use glutamine/glutathione in critically ill patients with organ dysfunction, as it is associated with increased mortality 1
Recognize that most "glutathione supplementation" claims are not supported by clinical guidelines, and the evidence is limited to glutamine as a precursor in highly specific clinical scenarios 2, 8