Kidney damage, seizures, heart rhythm irregularities, and death may result in severe cases. There is no real antidote for a theobromine overdose. Supportive care can be given, and vomiting can be induced if the case is caught early enough. Gourmet chocolate goodies, however, often contain more chocolate. This is not good for your dog, because a dog's body cannot process excess salt.
Salt can accumulate and cause kidney disease in old age.
At any time in a dog's life, if salt is given in extreme excess, it could cause your dog's kidneys to react and swell. If your dog gets any leftovers from your table, make absolutely certain that there is no salt in these foods. Remember that butter has salt in it, too. Read the labels on the food products you use in your home and the dog food and treats you buy for your dog. I occasionally give my dogs very small pieces of things that I know are safe for them to eat.