Jack
My Jack is going through the same thing right now. A blood test showed that he is losing protein in his blood so we have had a stool sample to check for parasites, a urine sample to check kidneys, an ultrasound to check for tumors, and this week we are trying endoscopy to check the cells in the lining of his intestines. I guess that my point is that there are a variety of reasons that could be causing Bentley's stomach problems and with time and tests the vet will figure it out. Please know that I completely understand how tough the "waiting game" is and I'm thinking of you and hoping your vet finds the problem quickly and gets him on the path to feeling better.
Jack, Bailey, Molly, and Danny's Mom