What causes headache?

There can be many causes for headache, here are some of them:

  • dehydration or starvation
  • fever, heat illness or hypothermia
  • stress
  • illness
  • injury
  • bleeding (especially sudden and intensive ache)
  • taking excess salt/sodium
  • blood pressure
  • sinusitis
  • acidity
  • indigetion
  • meningitis
  • brain tumor
  • servical spondylitis