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L-Glutamine Side Effects & Safety

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

Safety Profile

Overall safety rating: Generally Safe

Potential Side Effects

  • Very well tolerated at standard doses
  • Mild GI discomfort at very high doses (>20 g)
  • Theoretical concern about glutamate conversion in neurological conditions

Drug & Supplement Interactions

  • Lactulose — glutamine may reduce lactulose efficacy for hepatic encephalopathy
  • Anti-seizure medications — theoretical concern about glutamate excitotoxicity
  • Chemotherapy — consult oncologist before use

Maximum Dose

Do not exceed: 40 g/day has been used in clinical settings; 20 g/day is a typical upper dose for supplements

Full L-Glutamine Guide

References

  1. (). Glutamine supplementation in serious illness: a systematic review of the evidence. Critical Care Medicine. DOI
  2. (). Glutamine and the preservation of gut integrity. The Lancet. DOI