Enjen

I need help, I went to my GI dr wed. He thinks I have celiac disease and/or ulcerative Colitis. I have a endoscopy scheduled for monday morning. He already started me on a gluten free diet (as of wed night). And the only tolerable thing i have been able to stomach is the gluten free bagels ? i'm hungry and everything has a very ricey taste. I like rice, but...