Nervous Problems The most commonly reported side effect of the rabies vaccine is a sudden occurrence of epilepsy and seizures. Because of the nature of rabies, the vaccine often attacks the nervous system, causing muscle weakness or brain and spinal issues similar to rabies itself.
Immediate Side Effects Reactions immediately after your pet receives the vaccine are fairly common. Side effects appearing within hours of vaccination include vomiting, lethargy, fever, loss of consciousness and even death.
Other Side Effects Other reported side effects from the rabies vaccination include autoimmune diseases, allergies, skin problems, digestive disorders and fibrocarcinomas, a type of cancer, at the injection site.