If you are desperate, ask your doctor about Sulcralfate (Carafate): it helps protect and coat the lining of the esophagus, stomach and upper small intestine by shielding their exposure to stomach acid, so that healing can occur. (infantreflux.org)
Gluten is a protein found in wheat, and other similar proteins found in rye, barley and oats that when ingested by people suffering from coeliac disease damages the upper small intestine. (foodreactions.org)
Foods have to be at a certain acidity before they are allowed to pass from the stomach into the upper small intestine. (onnit.com)