My 2 year old boxer Riley has been though a bunch of episodes in the last two months. One day we arrived home to find he had vomitted about 30 times during the day and was very sick. He spent four days at the vet and countless tests and IV fluids and they could never find anything wrong. Barium x-rays revealed nothing but seemed to calm his stomach down and he returned to normal. Now 2 months later he is back to licking and swallowing air and trying to consume plants (like his stomach is upset). I have had him on various acid reducers and Prilosec which do help, but we are very frusterated. My only one correlation is I rotate the dog's food about every 2-3 months or so. Whenever he has one of these episodes it is always about 2 weeks into the new food?? I am probably going to take him to a specialty vet in Phoenix soon, but I wanted to ask if anyone had any ideas or experience with this?? I hear people talk on here about their boxers being prone to ulcerative colitis and other things. Does this sound like that?? Thanks for any help or advice you can give.