Amara, S. (2008). Oral glutamine for the prevention of chemotherapy-induced peripheral neuropathy. Annals of Pharmacotherapy, 42, 1481–1485.

The purpose of the study was to determine what role glutamine plays in preventing peripheral neuropathy.

The author searched PubMed from 1990 to May 2008 with the key words glutamine, chemotherapy, peripheral neuropathy, neurotoxicity, safety, paclitaxel, platinum compounds, and vinca alkloids. To be included, studies had to evaluate the role of oral glutamine in preventing and treating chemotherapy-induced peripheral neuropathy (CIPN). Studies were excluded if they used glutamine in the reduction of other radiation or chemotherapy-induced related toxicities such as mucositis, cardiotoxicity, diarrhea, and cachexia.

Three clinical trials were reviewed for sample, inclusion/exclusion criteria, study design, and results given. No type of measurement was used to review the study quality. Of note, the article did not state if other studies were found in the literature review.

• The total sample of the three studies combined was 195 patients.
• Patients in study 1 had stage IV breast cancer, no mention of stage was made in study 2, and patients in study 3 had metastatic colon cancer.
• In study 1, 33 patients on glutamine and 30 not on glutamine received a first cycle of high-dose paclitaxel.
• In study 2, 29 patients were placed in a control group and 17 in a glutamine group receiving first cycle of high-dose paclitaxel.
• In study 3, 42 patients received glutamine and 44 did not, receiving one cycle (two doses) of oxaliplatin.

Study 1 suggested that glutamine helps to decrease symptoms of peripheral neuropathy.  Study 2 suggested that glutamine can help prevent some symptoms of CIPN. And, finally, study 3 suggested that glutamine may reduce the occurrence of CPIN.

Although each study had a small sample size, glutamine did appear to help reduce symptoms of neuropathy. However, the systematic review concluded that a lack of sufficient evidence existed to recommend oral glutamine for the prevention of CIPN. Glutamine could be beneficial in patients receiving high-dose paclitaxel and oxaliplatin.

• Regarding limitations, none of the studies were placebo-controlled and endpoints were subjective.
• Criteria to evaluate CPIN differed among all three studies and no standard tool or measure was used to document CPIN.
• The long-term effect of glutamine was not studied, and the symptoms may have been reversed after chemotherapy discontinuation.
• The use of only one database likely hindered the research, as did the small number of studies included.

The safety and tolerability of glutamine was not mentioned.