Cluster headaches are rare headaches that occur in groups or clusters. more...
Cluster headache sufferers typically experience very severe headaches of a piercing quality near one eye or temple that last for between 15 minutes and three hours. The headaches are unilateral and occasionally change sides.
Cluster headaches are frequently associated with drooping eyelids, conjunctival injection (which results in red, watery eyes), tearing, constricted pupil, eyelid edema, nasal congestion, runny nose, and sweating on the affected side of the face. The neck is often stiff or tender in association with cluster headaches, and jaw and teeth pain is sometimes reported.
During an attack, the person often is unable to be still and may pace. Sensitivity to light is more typical of a migraine, as is vomiting, but they can be present in some sufferers of cluster headache.
In episodic cluster headache, these attacks occur once or more daily, often at the same times each day, for a period of several weeks, followed by a headache-free period lasting weeks, months, or even years. Approximately 10-15% of cluster headache sufferers are chronic; they can experience multiple headaches every day for years.
Cluster headaches are occasionally referred to as "alarm clock headaches", as they can occur at night and wake a person from sleep at the same time each night or at a certain period after falling asleep. Other synonyms for cluster headache include Horton's syndrome and "suicide headaches" (a reference to the excruciating pain and resulting desperation).
The location and type of pain has been compared to a "brain-freeze" headache from rapidly eating ice cream; this analogy is limited, but may offer some insight into the cluster headache experience. Persons who have experienced both cluster headaches and other painful conditions (childbirth, migraines) report that the pain of cluster headaches is far worse. One analogy is that of a burning ice pick being repeatedly stabbed through the eye into the brain.
Whereas other headaches, such as migraines are diagnosed more often in women, cluster headaches are diagnosed in men at a rate 2.5 to 3 times greater than in women. Between 1 and 4 people per thousand experience cluster headaches in the U.S. and Western Europe; statistics for other parts of the world are fragmentary. Latitude plays a role in the occurrence of cluster headaches, which are more common as one moves away from the equator towards the poles. It is believed that greater changes in day length are responsible for the increase.
While the immediate cause of pain is in the trigeminal nerve, the true cause(s) of cluster headache is complex and not fully understood. Cluster headaches are a type of vascular headache and the intense pain of an attack is also associated with the dilation of blood vessels.
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