Headache management for the pain specialist.

Headache is a common symptom caused by a wide variety of diseases. Primary headaches include migraine, cluster headache, tension-type headache, and other less common diseases. It is important to differentiate these headaches from secondary headaches caused by vascular, neoplastic, infectious, metabolic, or toxic disorders. Most primary headaches have a genetic basis, with environmental factors acting as triggers. Recent advances in basic research resulted in the development of more specific and effective therapies. Medication-overuse headache is a very common cause of chronic daily headache. Detoxification from the offending drug is essential for headache improvement. Cervicogenic headache is common and needs to be diagnosed correctly since it may require specific therapy. Nerve blocks are useful for some patients with primary, as well as secondary, headaches.