Here's why it's so urgent:
* Trauma: Being hit by a car can cause severe internal injuries, even if they're not immediately obvious.
* Seizures: Foaming at the mouth and uncontrollable shaking are classic signs of a seizure, which can be caused by head trauma, internal bleeding, or other injuries.
* Shock: The dog might be going into shock due to blood loss or pain.
What to do:
1. Call your veterinarian or an emergency animal hospital immediately. Explain the situation clearly and follow their instructions.
2. Do not attempt to move the dog unless it's in immediate danger (like being in the middle of a road). Moving a dog with potential spinal injuries can worsen the situation.
3. Keep the dog calm and still. Don't try to give it water or food.
4. If the dog is bleeding, apply gentle pressure to the wound with a clean cloth.
5. If you can safely transport the dog, take it to the veterinarian as soon as possible.
Remember, time is of the essence. Get the dog to a veterinarian right away for proper diagnosis and treatment.