Cluster headache

Cluster headache (CH) is a neurological disorder characterized by recurrent severe headaches on one side of the head, typically around the eye. There is often accompanying eye watering, nasal congestion, or swelling around the eye on the affected side. These symptoms typically last 15 minutes to 3 hours. Attacks often occur in clusters which typically last for weeks or months and occasionally more than a year. The cause is unknown. Risk factors include a history of exposure to tobacco smoke and a family history of the condition. Exposures which may trigger attacks include alcohol and nitroglycerin. They are a primary headache disorder of the trigeminal autonomic cephalalgias type. Diagnosis is based on symptoms. Recommended management includes lifestyle changes such as avoiding potential triggers. Treatments for acute attacks include oxygen or a fast-acting triptan. Measures recommended to decrease the frequency of attacks include steroid injections, civamide, or verapamil. Nerve stimulation or surgery may occasionally be used if other measures are not effective. The condition affects about 0.1% of the general population at some point in their life and 0.05% in any given year. The condition usually first occurs between 20 and 40 years of age. Men are affected about four times more often than women. Cluster headaches are named for the occurrence of groups of headache attacks (clusters). They have also been referred to as 'suicide headaches'. Cluster headaches are recurring bouts of severe unilateral headache attacks. The duration of a typical CH attack ranges from about 15 to 180 minutes. About 75% of untreated attacks last less than 60 minutes. The onset of an attack is rapid and typically without an aura. Preliminary sensations of pain in the general area of attack, referred to as 'shadows', may signal an imminent CH, or these symptoms may linger after an attack has passed, or between attacks. Though CH is strictly unilateral, there are some documented cases of 'side-shift' between cluster periods, or, rarely, simultaneous (within the same cluster period) bilateral cluster headaches. The pain occurs only on one side of the head, around the eye, particularly above the eye, in the temple. The pain is typically greater than in other headache conditions, including migraines. The pain is typically described as burning, stabbing, drilling or squeezing, and may be located near or behind the eye. As a result of the pain, those with cluster headaches may experience suicidal thoughts during an attack (giving the alternative name 'suicide headache' or 'suicidal headache'). It is reported as one of the most painful conditions. The typical symptoms of cluster headache include grouped occurrence and recurrence (cluster) of headache attack, severe unilateral orbital, supraorbital and/or temporal pain. If left untreated, attack frequency may range from one attack every two days to eight attacks per day. Cluster headache attack is accompanied by at least one of the following autonomic symptoms: drooping eyelid, pupil constriction, redness of the conjunctiva, tearing, runny nose and less commonly, facial blushing, swelling, or sweating, typically appearing on the same side of the head as the pain.