Polly: Often, glutamine is prescribed to help repair your intestinal lining. Please be aware that it interacts with other amino acids. In fact, no amino acid acts completely by itself. In the case of glutamine, it can lower branch chain aminos, lower taurine and it might raise citrulline, arginine, and alanine aminos. 
In the intestines, the glutamine will convert into glutamate and release ammonia.  The ammonia can interfere with many bodily processes including interference with alphaketoglutaric acid, which is needed for energy production. Long time exposure to excess ammonia can lead to permanent nerve damage.
Since many of us might be low on the amino acids used to remove ammonia, it might be a very good idea to bring up the level of these amino acids before starting glutamine. Alphaketoglutaric acid helps keep ammonia under control, and it is fairly likely that it is low. I also believe that low taurine levels should be corrected before starting the glutamine. I think that amino acid supplementation must be used in a particular treatment sequence for best results. The trick is to find out that sequence.
Shelley: Has anyone experienced major brain fog effects from taking glutamine?
Mary in Pennsylvania: Shelley, YES!!! I had major brain fog from all the ammonia created from pathogenic bacteria and candida in my gut. Then when I started to use the glutamine it got even worse, but I didn’ t realize it was the glutamine making me worse (even the doctor didn’ t know). It was this forum that helped me get the situation under control. I used some supplements that targeted getting rid of the excess ammonia. The supplement that helped me the most was alpha-ketoglutarate, plus I stopped taking the glutamine for a while. Now I take it but sparingly. I might take a teaspoon of the powder that is the equivalent of about 5 grams once or twice a week.
One more thing about glutamine. I do a lot of research on supplements before I just start using them and I never saw anything about the excess ammonia that is created. The only caution that I saw in print was supplementing with glutamine pulls water out of the colon and therefore it was necessary for people to take high fiber and drink lots of liquid to overcome possible constipation. Oh, I do remember one article but can’ t find it now that indicated the doctors’ concern on excess (I think) hydrogen or nitrogen impacting the brain. This whole thing has taught me a very valuable lesson…Keep a journal and track ALL symptoms. Then you have a better idea of what supplement is causing what symptoms.
Mrs. Generic: How much glutamine are people using for their leaky gut?
Polly: Typical doses are from 3 g to 8 g per day, although doctors have used up to 40 g per day to stop diarrhea. The best price I’ ve seen on glutamine is from Cambridge Nutraceuticals. (800) 265-2202 This company can also provide you with some papers on glutamine and the book The Ultimate Nutrient Glutamine.
If you try glutamine, divide your doses throughout the day. It can cause constipation. Be careful if you have weak kidneys. Large amounts of added protein like glutamine may be hard on weak kidneys. Make sure you have adequate supplies of coenzyme B6 before using glutamine. Coenzyme B6 is needed to convert glutamic acid into GABA. Without adequate coenzyme B6, extra glutamine will certainly cause an imbalance that would contribute to seizures. Anyone prone to seizures should be very wary of using glutamine, because glutamine will convert to the excitotoxin glutamate and will release ammonia, both of which could contribute to seizures.
Since all the aminos are interconnected, a blend or a particular sequence of support may be necessary. You might want to make sure your branch chain aminos, your taurine, and the aminos that help remove ammonia are adequate before trying the glutamine. This is where an amino acid assay and some professional help come in very handy. But there is so much to learn about aminos, that even the experts don’ t know everything. So don’ t over-do any single amino, and pay close attention to how you react/feel.
Andy: Don’ t worship a blood test like the amino acid assay. Use it as guidance to the extent it is helpful. The idea is to make you healthy, not to make a piece of paper that comes from the laboratory have wonderful numbers on it.