Husband's GI Pain

For the last six weeks my husband has been in excruciating pain.  I simply do not know what to do anymore.  First we were told it was peptic ulcer disease.  After Nexium, Prevacid and Prilosect failed to help with the pain we saw a local GI specialist here.  He said to continue with the Nexium.  While it worked briefly, things got progressively worse.  He finally relented and went to the ER doubled over in the fetal position.  They performed an abdominal series of x-rays and everything was normal.  He was dischared only to return about three hours later in more severe pain.  An ultrasound of the gallbladder was normal.  He was discharged a second time.  The following morning an endoscopy was performed and, quel surprise, it was negative for ulcers and cancer.  Twenty four hours have passed and my husband is still in pain.  No relief.  He is having diarrhea, bloating ( to the point which he says he feels as though he will " explode" )  Our GI told us that " one step at a time is all we can do."  Can I demand a specific test of the hospital should he go back?  Can I demand he be admitted?  Please help.  The Dr. told us he has something called bile gastritis.  NOTHING IS HELPING!!