Answer:
The first is to know how can you possibly know that your dog has a headache? You can only assume it. If you assume the dog may have a headache because shakes the head, you must look instead for an infection in the ears or mouth. In any case, do not give human medicines for headache to a dog, start by visiting a Veterinarian to find out what causes the problem. In the meaning time you can give some Chamomile tea.