Chronic abdominal pain

My son has been having stomach and abdominal pain for almost a year now.  We have had many tests done including a scope of his stomach and small intestines, allergy testing, ct scan, gall bladder check.  While his allergy testing did come back with some food allergies we have been keeping him away from as much of what he is allergic to as we can.  He will feel mostly fine for a couple of weeks and then his abdomin (abdomen) will start to hurt so bad that he wakes up at night.  Instead of getting better, the pain seems to be getting steadily worse.  I am at a loss as to what to do next.  Any suggestions?

[patient915]

Welcome to the gastroenterology community!  First, he should be eliminated from 100% of what he is allergic to.  What was he allergic to?  Has he had any sort of testing on his large intestine?