Sucralfate is bad for kidneys only when the dog has pre-existing kidney conditions. It is one of the side effects of Sucralfate in dogs. Other Sucralfate side effects in dogs include backache, feeling dizzy or lightheaded, itching, skin rash, passing gas, stomach cramps, and headache. You should also be on the lookout for any sort of allergic reaction during the dosage. Take your pet to the vet immediately if you notice such reactions.