What causes a dog to seizue all over its body?

A dog experiencing whole-body seizures may be due to various reasons such as distemper, epilepsy, poisoning, rabies, encephalitis, and more.

Distemper: When a dog contracts the distemper virus, it may exhibit symptoms such as lethargy, loss of appetite, vomiting, diarrhea, and biphasic fever. As the disease progresses, the dog may experience generalized or partial body seizures. This virus is more susceptible to unvaccinated puppies. If your dog hasn't been vaccinated, you should consider this possibility and take it to a pet hospital for confirmation.
Epilepsy: If a dog experiences seizures that last for a short period and then subside, and the dog's behavior and appetite are normal before the seizure, it may be suffering from epilepsy. As epilepsy is not curable, the owner can only purchase anti-epileptic drugs from a pet hospital to control the condition. During a seizure, the owner should remove the dog's tongue from the mouth to prevent it from biting itself.
Poisoning: If a dog accidentally ingests toxic substances such as rat poison, chocolate, or disinfectant, the toxins can invade the nervous system and cause seizures. This condition has a high mortality rate, and immediate veterinary attention is required, including large-scale fluid therapy and liver protection.
Rabies: The most obvious sign of a dog infected with rabies is whole-body seizures, indicating that the rabies virus has invaded the dog's nervous system. Other symptoms include madness, photophobia, and hydrophobia. If this is the case, the owner should immediately isolate the dog and take precautions to avoid being bitten, notify relevant authorities for disposal.
Encephalitis: A dog with encephalitis will also experience continuous seizures, accompanied by disorders of consciousness, coordination issues, and colliding with obstacles. If you suspect your dog has encephalitis symptoms, take it to a pet hospital as soon as possible for emergency treatment.

No matter what the cause of the seizures, it is recommended to seek veterinary attention promptly.