Some dogs can be maintained with just a change in diet. The diet most useful would be one free of additives and with only one protein source that is easily digestible and new to your dog. Other dogs will need some kind of medicine to control their illness. Update - I have heard from 2 IBD dog owners who reported severe side effects from Flagyl . As with all drugs, check with your vet immediately any side effects especially any unexpected ones.
Some dogs are more sensitive to certain drugs than others.
It is definitely helping my boy. I also recommned homeopathy. I recently heard that the supplement Glucosamine is supposed to help IBD dogs. Another dog was helped by Pepto Bismol. And yet another by Bran added to diet.