Your body usually produces sufficient glutamine, an amino acid you need to make proteins, on its own. Sometimes you may need extra glutamine, however, if you are injured or are participating in very heavy exercise, according to the University of Maryland Medical Center. You also get glutamine through your diet from foods containing protein, including meat, poultry, dairy products, cabbage and raw spinach. Don't take glutamine supplements without first consulting with your doctor to verify they are safe for you.
Potential Serious Side Effects
Even if you overdose on glutamine, it isn't likely to cause symptoms that would be life-threatening, according to Drugs.com. More serious side effects that merit immediate medical treatment include an allergic reaction, hearing problems, chest pain or symptoms of infection, which can be similar to those of the flu.
Minor Side Effects
You're more likely to experience minor side effects, even when taking relatively high doses of glutamine, although you should be monitored by a doctor when taking more than 1,500 milligrams per day. Some potential side effects include itching or a rash, sweating more often, swelling in your feet or hands, pain in your back or other muscles or joints, feeling dizzy or tired, headache, runny nose, dry mouth, stomach pain, gas, vomiting or nausea.
Some people, including those with liver disease, kidney disease or Reye syndrome, should avoid glutamine supplements. People with decreased kidney function may need a lower dose of glutamine. Those who are pregnant or nursing may also want to avoid glutamine supplements because their effects on these populations haven't been well studied.
Glutamine supplements may interact with chemotherapy medications, making them more effective and helping to reduce their side effects, according to the University of Maryland Medical Center. The center, however, also notes that research is conflicting in this area, and glutamine might also cause more tumors to grow. Speak with your doctor before combining this supplement with cancer medications.