Baron had the same problem. The breeder had him on Purina puppy. He had diarrhea all the time. The vet said he had a sensitive stomach which alot of small breeds have. I set out to find what he did the best on. It was Royal Canin # 33 for puppies. No more upset stomach,Gas or diarrhea. It's available @ Super pets for $9.99 for a 3 pound bag. I hope this helps...
Baron's mommy