L-Glutamine and Reduced Oral Mucositis Severity

Research synthesisModerate evidenceSmall effect5 studies · 3 beneficial · 2 neutral · 0 harmful

Across 5 studies, 3 reported beneficial effects (one moderate, two small) and 2 found neutral effects on reducing oral mucositis severity. Most evidence comes from clinical populations with cancer, particularly head and neck cancer patients undergoing radiotherapy or chemoradiotherapy. The median study duration was 49 days, and the most-studied dose was 5 g of L-glutamine (in one RCT), though dose information was limited across the included papers.

Effective dose range: 5 g daily (single trial)
Studied populations: patients with head and neck cancer undergoing radiotherapy, pediatric cancer patients receiving chemo-/radiotherapy, general cancer patients

Caveats: Available evidence is overwhelmingly positive (3 of 5 studies beneficial) — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). Evidence base is small (only 5 studies) — conclusions should be considered preliminary. Two neutral studies did not reach statistical significance, and one used NCI scale which showed no difference.

Generated May 13, 2026

Doses used in studies

g/day: 5 (median 5, IQR 5–5) — 1 study

Time to effect

Median: 7 weeks · IQR 7 weeks–7 weeks · Range 7 weeks–7 weeks — Reported in 1 of 5 studies

Safety in these studies

Overall tolerabilityReported
Ten interventions were found to have some benefit with regard to preventing or reducing the severity of mucositis associated with cancer treatment.
from: Interventions for preventing oral mucositis for patients with cancer receiving treatment.

5 of 5 papers

Interventions for preventing oral mucositis for patients with cancer receiving treatment.
- 2011-04-13
- Meta-Analysis · n = 131
- The Cochrane database of systematic reviews 2021(3)
- - Helen V Worthington
  - Jan E Clarkson
  - Gemma Bryan
  - Susan Furness
  - Anne-Marie Glenny
  - Anne Littlewood
  - Martin G McCabe
  - Stefan Meyer
  - Tasneem Khalid
- PubMed: 21491378
- DOI: 10.1002/14651858.cd000978.pub5
1 Insight on
- Reduced Oral Mucositis Severity
- High evidence
- Highly Cited
- Clinical
Ten interventions, where there was more than one trial in the meta-analysis, showed some statistically significant evidence of a benefit (albeit sometimes weak) for either preventing or reducing the severity of mucositis, compared to either a placebo or no treatment. These ten interventions were: aloe vera, amifostine, cryotherapy, granulocyte-colony stimulating factor (G-CSF), intravenous glutamine, honey, keratinocyte growth factor, laser, polymixin/tobramycin/amphotericin (PTA) antibiotic pastille/paste and sucralfate.
Effect
Beneficial
Effect size
Small
Significant
Yes
L-arginine vs. L-glutamine oral suspensions for radiation-induced oral mucositis: a triple-blind randomized trial.
- 2025-07-03
- RCT · n = 23
- Journal of cancer research and clinical oncology 151(7)
- - Fatma E A Hassanein
  - Christine Mikhail
  - Sarah Elkot
  - Asmaa Abou-Bakr
- PubMed: 40603739
- DOI: 10.1007/s00432-025-06213-x
6 Insights on
- Reduced Oral Mucositis Severity
- High evidence
- Clinical
By week 5, WHO scale scores differed significantly among groups (p < 0.001), with arginine and glutamine groups exhibiting lower mucositis severity than the maltodextrin group.
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Dose
5 g + maltodextrin 5 g
Nutritional and Supplemental Interventions for Prevention and Treatment of Oral Mucositis in Pediatric Oncology.
- 2025-11-11
- Systematic Review
- Nutrients 17(22)
- - Razvan Mihai Horhat
  - Alexandru Alexandru
  - Cristiana-Smaranda Ivan
  - Norberth-Istvan Varga
  - Madalina-Ianca Suba
  - Elena Ciurariu
  - Monica Susan
  - Razvan Susan
  - Adrian Cote
- PubMed: 41305573
- DOI: 10.3390/nu17223521
4 Insights on
- Reduced Oral Mucositis Severity
- High evidence
- Rigorous Journal
- Clinical
Interventions tested included systemic supplements (e.g., glutamine, zinc, and bovine colostrum), topically applied agents (e.g., honey, vitamin E, Aloe vera, and olive oil), and nutrient-containing rinses (e.g., chamomile, Caphosol, and Traumeel S). Honey-based interventions showed promising outcomes.
Effect
Neutral
Effect size
Small
Significant
No
Update on the treatment of chemotherapy and radiotherapy-induced buccal mucositis: a systematic review.
- 2023-04-29
- Systematic Review
- Acta odontologica latinoamericana : AOL 36(1)
- - Schilin Wen
  - Leonardo Brito
  - Javiera Santander
  - Gonzalo Conteras
- PubMed: 37314054
- DOI: 10.54589/aol.36/1/3
1 Insight on
- Reduced Oral Mucositis Severity
- High evidence
- Clinical
Dentoxol mouthwashes, Plantago major extract, thyme honey extract, zinc oxide paste, vitamin B complex combined with GeneTime, and the consumption of L-glutamine are effective in diminishing the severity of OM.
Effect
Beneficial
Effect size
Moderate
Significant
Yes
Effects of L-glutamine and hyaluronic acid associated with photobiomodulation on oral mucositis: a randomized clinical trial.
- 2025-04-28
- RCT · n = 24
- Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer 33(5)
- - Rodrigo Wilmes Dos Santos
  - Allisson Filipe Lopes Martins
  - Sebastião Silvério Sousa-Neto
  - Marília Oliveira Morais
  - Victor Hugo Lopes de Oliveira Moreira
  - Diego Antonio Costa Arantes
  - Angélica Ferreira Oton-Leite
  - Nilceana Maya Aires Freitas
  - Cláudio Rodrigues Leles
  - Elismauro Francisco Mendonça
- PubMed: 40295318
- DOI: 10.1007/s00520-025-09480-z
3 Insights on
- Reduced Oral Mucositis Severity
- High evidence
- Clinical
There were no differences when using the NCI scale.
Effect
Neutral
Effect size
Small
Significant
No

L-Glutamine and Reduced Oral Mucositis Severity

Interventions for preventing oral mucositis for patients with cancer receiving treatment.

L-arginine vs. L-glutamine oral suspensions for radiation-induced oral mucositis: a triple-blind randomized trial.

Nutritional and Supplemental Interventions for Prevention and Treatment of Oral Mucositis in Pediatric Oncology.

Update on the treatment of chemotherapy and radiotherapy-induced buccal mucositis: a systematic review.

Effects of L-glutamine and hyaluronic acid associated with photobiomodulation on oral mucositis: a randomized clinical trial.