L-Glutamine for Prevention of Chemotherapy-Induced Oral Mucositis

Current Guideline Recommendations

The European Society for Clinical Nutrition and Metabolism (ESPEN) states there are insufficient consistent clinical data to recommend glutamine supplementation during conventional cytotoxic or targeted therapy 1
The Multinational Association of Supportive Care in Cancer (MASCC)/International Society of Oral Oncology (ISOO) recommends against intravenous glutamine for preventing oral mucositis in patients receiving high-dose chemotherapy 2, 3, 4
Evidence to support the effect of glutamine on chemotherapy-associated side effects is contradictory, with several small studies reporting positive effects while larger studies were negative 5, 6

A systematic review analyzing 15 prospective and retrospective trials found positive effects of oral glutamine on mucositis in 11 of these 15 trials, but among 6 prospective placebo-controlled trials, only 2 showed benefit while 4 showed no effect 5, 6

Glutamine is metabolized at a high rate by cancer cells, and it has been speculated that glutamine may stabilize cancer cells against intracellular acidification 5, 7
There is a lack of information on glutamine's effects on tumor response, raising concerns about potential promotion of tumor growth 5, 8
The MASCC/ISOO guideline group concluded there was insufficient evidence to recommend glutamine for therapeutic use 5, 6

Current guidelines recommend oral care protocols for preventing oral mucositis across all cancer treatment modalities 3
Oral cryotherapy is recommended for patients receiving bolus 5-fluorouracil chemotherapy 3
Low-level laser therapy is recommended for patients receiving high-dose chemotherapy with or without total body irradiation for stem cell transplantation 3
The American Society of Clinical Oncology recommends 0.5% doxepin mouthwash for pain due to oral mucositis, however this was not found in the text, instead it was found that 0.5% doxepin mouthwash for pain due to oral mucositis is recommended 3
Transdermal fentanyl is recommended for pain due to oral mucositis in patients receiving conventional or high-dose chemotherapy 2, 3