It all started a few months back when my little guy had a reaction to the lepto in one of his boosters. He had a reaction, the vet saw him, gave his a steroid injection and sent him on his way. He seemed fine for a day then it started all back up. The main issue was diarrhea mixed in with some minor vomiting. I took him back to the vets where they did a stool exam and said his bad to good bacteria in his stomach was messed up (something about campi). My little guy was put on a low fat diet for about a week and slowly weened back on his food. All was going great till @ 2 weeks ago when he had to get his final booster... which again contained lepto. Again he had a reaction, diarrhea and vomiting ensued. He has been to 2 diffrent vets now and both did stool exams and neither saw anything out of the ordinary. I have since then slowly introduced back to his old food, but this time its not going so well. Both vets recommend I put him on some kind of ID food but all i have seen are pretty low quality foods. He was doing fine on his old food till this whole booster ordeal came about. Basically I need some advise. Im gonna try again today to try and slowing switch him from boiled chicken and rice back to his old food. If it does not work, im at a dead end.