There is no harm whatsoever in Zapping him that I know of! Zapping is not dangerous and is very low voltage. Rabies is a virus, so if he got rabies from the shot, it should be gone. He is doing better! After 3 sessions Zapping last night he was much improved and the look in his eyes was softer. I don't know if a dog can get full blown rabies from a shot or not, but I think if it could happen, Zapping would be his only hope. He is a big dog and old so he won't be getting any more shots. My brothers took him in and since they had never been to a vet or had him get shots, they didn't know what to specify and said only the necessary ones. He looks fine this morning. :) Thanks so much for the response!