So my shih tzu has been on a prescription food for the past few years- I had always trouble with him eating it and he also tried stealing other dogs food or our cat food. I took him to the vet three days ago for a check up and the vet says he's good to return to normal food. The problem is he refuses to eat any normal food. He's tried three different kinds and its day three and he hasn't eaten. I finally gave him some toast because he threw up bile this morning. bleh I need to stay strong but I'm worried. Any advice?