Sounds like something possibly going on with the biliary tree.
Any scopes or imaging done? i.e. Upper Endoscopy, ERCP, US or CT?
I don't know for sure but get a natural doctor to check his Piloric Valve to see if it is open. Very simple to close!
please no. That will add to the stomach problems
try some anti-depressants to stop him giving up!!! I hope you find a cure :) x
Has your brother been checked for Sphincter of Oddi Dysfunction? I'll send you a link about it.
More details pertaining to history, provisional diagnosis and basic investigations are mandatory.