@lhelbling You mentioned concussion. I am still trying to recover from one myself. I bumped the bridge of my nose on the first of April. I iced it.. went on with life. No broken bone and nothing but a small knot and a greenish bruise. I kept having a nagging headache, I got worse upon rising and I started to tire sooner on walks. I also became more nauseous than usual. It took me 4 week to remember I hit my nose. I still do not remember exactly how I did it. I did go to my family doctor. With his exam he said had a concussion and ordered a ct scan to rule out any sinus or brain damage. I have had to move slowly and not concentrate on anything for long. Just close my eyes sometimes to shut the world out. My point is he may still be having effects from the concussion.. it can last for months not just a few weeks. I am a little past the 6 weeks and can tell it is going to take a month or so morre to recover. I am older, but your son is at an age where he has to do more.. his school work for one. My son had a concussion when he was 16 or so and it was about impossible to keep him from pushing it. School.. work and interacting with friends. Finally threatened to tie him down and finally he was on his way to healing and he had stomach problems too…. long before they had many of the stomach medications they have now. The flu can take a long time to bounce back from.

Instead of the normal barium swallow test you might ask for one that involves food. There are two.. one involves one containing barium which usually is eggs and bacon and in the South maybe grits or toast. The other is swallowing different consistency foods. Just because what he vomits is clear does not mean he is getting the nutrients. I vomit clear mucus and sometimes it just comes up.. not really vomitting… they say it is stomach mucosa.. mucus containing acid. A type of reflux. I have achalasia, Barrett's esophagus and gastroparesis. All which should show in a barium swallow test and or endoscopy or what they call a bravo test..