My cat Aki, the one in my avatar pic got a Leukemia vac when she was a kitten a year after having her first series. She had had no problem when she first had it but this 3rd shot she couldn't walk that night and was in massive pain all night. She cried. and her leg was swollen. Took her to the vet very next morning (we have an emergency vet but it is over an hour away). They said it was from the shot. They don't give it to her now. But she is not a fighter so I am not worried. But I was scared to ever give her that shot again. Dogs must be different? They haave never offered to give her and allergy med prior.