I dont know if this will help or not but here goes. Back in December, Luke was throwing up about every 2-3 days. I was feeding him mainly dry Purina Sensitive. Also he was having difficulty having bm's. I suppose he was throwing up because not much was coming out in bm's. He got severely constipated and then to the vet 4x, finally got him unstopped. I switched from dry food to canned Wellness no grain and canned w/d. He hasnt thrown up since middle of December and he no longer has bm problems... Kay in NC