A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck that can result in headache. Several areas of the head and neck have pain-sensitive structures, which are the cranium, muscles, nerves, arteries and veins, subcutaneous tissues, eyes, ears, sinuses and mucous membranes.
There are many types of headache, and the causes range from harmless to life-threatening. The description of the headache, together with findings on physical examination, determine the need for any further investigations and the most appropriate treatment.
The most common types of headache are the “primary headache disorders”, such as tension-type headache and migraine. They have typical features; migraine, for example, tends to be pulsating in character, affecting one side of the head, associated with nausea, disabling in severity, and usually lasts between 3 hours and 3 days. Rarer primary headache disorders are trigeminal neuralgia (a shooting face pain), cluster headache (severe pains that occur together in bouts), and hemicrania continua (a continuous headache on one side of the head).
Secondary headaches may be caused by problems elsewhere in the head or neck. One of these is cervicogenic headache which is pain arising from the neck muscles, discs, facet joints or nerves. Another is medication overuse headache which may occur in those using excessive painkillers for headaches, paradoxically causing worsening headaches.