Secondary headaches — headaches which occur as a result of underlying local or systemic pathology e.g. trauma or injury, Cranial or cervical vascular disorders, Non-vascular intracranial disorders, Exposure to withdrawal from a substance, Infection, Disorders of homeostasis, Disorders of the cranium, neck, eyes, ears, nose, sinuses, teeth, mouth or other facial and cranial structures such as acute glaucoma, temporomandibular disorder or sinusitis, Psychiatric disorders such as somatization disorder.