I have an 11 yr old cat that is having a hard time with throwing up occasionally and icky, runny poop. This has gone one for some time, she's been to the vet, responded somewhat to antibiotics for a time, it comes back. She's had blood work done, he didn't find anything wrong there. She has been wormed. Also, she is very thin, any tricks to help her gain back some weight would be great. She feels fine, quite lively and happy, just her digestive tract seems to give her trouble. My main thought at this time is food intolerance. I am looking for a high quality single protein source, no grain type cat food for her, either dry or canned or frozen raw. If it could be found at a pet store, or other local store great, if not I will mail order it. So, I would love to hear suggestions, people's experiences with various cat foods, etc. Thanks for your help!