Lucky has bouts of diarrhea and vomiting about once every month. I frankly don't even worry any more. After 7 years of this (that's about 80 times of dyspepsia), I just fast him and, if I have the courage, chug about a tablespoon of Pepto Bismol into him. After about 24 hours, he's back to his old self. I do think it is a toy breed thing. I wouldn't cross poor genetics off my list, either. Lucky came from a BYB.