The pain can be so severe that it has been called the 'suicide' headache
The majority of sufferers are men (tenfold) – especially between the ages of 20 to 40
This rare group of headaches occur repeatedly (over one or several days) in groups or clusters – hence the name cluster headaches. They usually begin as a minor pain around one eye (always unilateral) and eventually spread to that entire side of the face. The pain becomes so severe that the disorder has been called the "suicide headache".
The majority of sufferers are men (tenfold) – especially between the ages of 20 to 40. The headaches are non-hereditary and not stress-related, and often triggered by alcohol. However, when the patient is in remission, alcohol has no effect as far as bringing on a cluster headache is concerned.
There are no clear-cut answers to the question of what causes cluster headaches, only clues. One such clue is a "cold spot" of reduced blood flow above the affected eye in thermograms taken of people who get untreated cluster headaches.
Cluster headaches follow a classic pattern that varies little among people who have them. They are often diagnosed based only on the person's description of his or her symptoms.
The classic symptoms of a cluster headache include the following:
Severe, excruciating headache pain begins as a dull ache deep in and around the eye and progresses to a deep, steady, boring, piercing pain. Occasionally the pain may spread to the teeth, forehead, temple, or cheek on that side. No aura precedes the pain. There is no accompanying nausea.
The pain always occurs on the same side and usually comes back at the same time of day, one to three times during the day and night. The pain often awakens the person one to two hours after he has gone to sleep.
The pain is usually at its worst within five to 10 minutes of starting and lasts 45 minutes to two hours. (Attacks may be as short as 10 minutes or as long as three hours.) Toward the end of the headache, there may be short peaks of pain before the headache goes away over a few minutes.
Unlike the migraine patient, who tends to curl up beneath a blanket in a dark room, the cluster patient is unable to remain still. During an episode, he is likely to engage in all sorts of intense, even bizarre, physical activity. Some people find relief by pacing or other physical activity. Lying down increases the pain.
After an attack, the person is free of pain but exhausted. Sometimes another attack will occur within a short time.
Many people have other symptoms that occur on the same side of the body as the pain and last about 45 minutes. These symptoms may include:
Stuffy nose (nasal congestion) followed by runny nose
Reddening of the eye with tears - on the same side as the pain
Widening or enlargement of the artery in the temple on the affected side which can be seen or felt
A droopy eyelid and constriction of the pupil (pupil gets smaller)
Extreme sensitivity to light
A red or flushed face
A person may have a cluster headache without having all of these symptoms.
Because cluster headaches occur infrequently and sometimes resemble sinus headaches, sufferers are often misdiagnosed. However, sinus headaches do not occur episodically several times a day. This misdiagnosis has sometimes led to unnecessary and futile surgery on sufferers in an attempt to cure the pain.
The history and physical exam are all that is needed to diagnose cluster headaches. Additional tests are only needed to help diagnose other conditions which may cause similar symptoms. See Diagnosis under Headaches.
As these headaches start suddenly and seldom last long, they may be difficult to treat. They respond poorly to most medication. Since cluster headaches cannot be cured, treatment focuses on reducing how often they occur, how severe the pain is, and how long the headaches last.
If taken at the first sign of an attack, ergotamine tartrate (the anti-migraine drug) and the triptan medications (e.g. sumatriptan) can provide relief. A form of this drug, dihydroergotamine, can also be administered by injection. Other treatment include: systemic corticosteroids, lithium and calcium-channel blockers.
Rapid inhalation of pure oxygen through a mask has proven efficacious.
If headaches do occur, the following may help you handle them:
Use the medication or treatment your doctor has recommended as early as possible in the headache. The sooner you can treat the headache, the less painful it may be.
Try to focus on the end of the attack. Cluster headaches are extremely painful but generally don't last long.
Pacing the floor or rocking in a chair provides temporary relief.
Surgery to cut the sensory nerves to the face of chronic sufferers has had limited success.
Avoid alcohol, which seems to trigger cluster headaches in nearly everyone who has them. When you are not in a cluster period, however, drinking alcohol will not usually trigger an attack.
Decrease, and if possible, stop smoking.
Try to maintain a regular sleep schedule. Changes in your normal sleep patterns (especially taking afternoon naps) seem to trigger cluster headaches.
Try to reduce your overall stress level. During a cluster period, headaches often develop when you relax following a very stressful time. Reducing stress may help avoid them.
Take any medication exactly as your doctor recommends. During a cluster period, when you are prone to headaches, your doctor may recommend that you take medications every day.
Reviewed by Dr Andrew Rose-Innes, Yale University School of Medicine, 2007