I adopted a dog from the shelter about a week ago and was trying to switch him from the Iams puppy formula to Halo puppy formula. Last night was the first night that he got a bowl of only Halo food. During the middle of the night he vomited and has had diarrhea ever since. I called the vet and they said to put him on a bland diet of chicken and rice until the diarrhea stops. Earlier in the week I noticed he was itching his hind end a lot and licking his rectum, he also likes to bite his feet and his breath smells like metal. Could this be an allergy to the new food? Does anybody have any other suggestions for helping with the diarrhea? I will be gone all day tomorrow and would rather not make my roommates take care of a sick dog. Finally, he has had at least 7 bowel movements within the last 12 hours and the last few I've noticed a few drops of blood, anybody know if this is just from "overuse" or should I be concerned?