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Cluster Headache FAQs

What are cluster headaches?

  • Cluster headache is an uncommon condition characterized by short-lived attacks of sudden, severe pain around one of the eyes. The word cluster is used because these headaches typically come in groups or bunches. A person may have several headaches a day for weeks or months, usually separated by headache-free periods of varying duration. Many more people have migraine or tension headaches than cluster headaches.
  • The International Headache Society (IHS) classifies cluster headaches as episodic (occurring in cycles) or chronic (long-term without significant breaks).
  • Episodic cluster headaches are defined as those that occur in periods (clusters) lasting from 7 days to 1 year. Clusters are separated by headache-free intervals lasting at least 2 weeks. Clusters usually last 2 weeks to 3 months.
  • Chronic cluster headaches are defined as those that occur for more than 1 year without remission (intervals in which headaches do not occur) or with remissions lasting less than 2 weeks. Chronic headaches are classified as those that are chronic from the start and those that develop from episodic headaches. Chronic cluster headaches are very hard to treat, and standard preventive drugs often do not help people with this type of cluster headache.
  • If a person has the following signs and symptoms, he or she might have what are called symptomatic clusterlike headaches.
    • Lack of a periodic pattern (a pattern that runs in cycles)
    • Continuing low-intensity headaches between high-intensity headaches
    • Partial or little response to standard treatments
    • Weakness or other signs on one side

How dangerous are cluster headaches?

Despite the intense pain of cluster headaches, they are not life threatening. They are harmful to a person’s quality of life, however, and sometimes induce depression and/or anxiety disorders, especially if the headaches are uncontrolled by medication or other therapies. Doctors conduct thorough examinations of persons with cluster headaches in order to rule out truly life-threatening causes of headache like tumors or subarachnoid hemorrhages (bleeding in the membranes of the brain).

Medically Reviewed by a Doctor on 11/17/2017
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Cluster Headaches - Symptoms

What were the symptoms of your cluster headaches?

Women with headache due to depression

Cluster Headache Symptoms

The pain of cluster headache is its defining and most dramatic feature. This pain comes on without warning (no forewarning symptoms such as the aura in classic migraine) and may begin as a burning sensation on the side of your nose or deep in your eye.

In addition to its one-sidedness, other characteristics separate cluster headaches from other headaches.

  • The headaches commonly come on just after you go to sleep.
  • Often the eye on your affected side will tear.
  • Your eyelid on the affected side will droop.
  • You will experience one-sided nasal stuffiness and runny nose.
  • Cluster headaches have seasonal variations. Most attacks occur in January and July, where the days are in turn the shortest and longest.

Read What Your Physician is Reading on Medscape

Cluster Headache »

Cluster headache (CH) is an idiopathic syndrome consisting of recurrent brief attacks of sudden, severe, unilateral periorbital pain.

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