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Cluster Headaches


Stephen D. Silberstein

, MD, Sidney Kimmel Medical College at Thomas Jefferson University

Last full review/revision Jul 2021| Content last modified Jul 2021

A cluster headache causes severe pain that is felt at the temple or around the eye on one side of the head and that lasts a relatively short time (usually 30 minutes to 1 hour). It is accompanied by nasal congestion or a runny nose and sometimes a drooping eyelid, tearing, and a flushed face. Headaches usually occur regularly during a 1- to 3-month period, followed by a headache-free period of months to years.

  • Excruciating pain occurs on one side of the head, causing the nostril and the eye on that side to water.
  • People are often restless and pace.
  • Doctors base the diagnosis on symptoms.
  • Oxygen (given by a face mask) or drugs are needed to treat headaches.
  • Most people with cluster headaches need to take drugs to prevent attacks from recurring.

(See also Overview of Headache.)

Cluster headaches are relatively rare, affecting about 4 of 1000 people in the United States. Cluster headaches are more common among men. They typically begin between the ages of 20 and 40.

Symptoms of Cluster Headaches

A headache attack almost always starts suddenly. It may begin with nasal congestion and a watery discharge from one nostril. Excruciating pain on the same side of the head follows and spreads around the eye. The pain peaks in intensity within minutes and usually lasts 30 minutes to 1 hour but may last 15 to 180 minutes. The pain often awakens people from sleep.

People with cluster headaches, unlike those with a migraine, cannot lie down. They frequently pace and sometimes bang their head on a wall.

After the attack, the eyelid on the same side as the headache may droop, and the pupil often constricts (called Horner syndrome). The area below the eye may swell, and the eye may water. The face may be flushed. Nausea may accompany the headaches.

Headache attacks may occur several times a day, often at the same time of day or night. They usually occur regularly during a 1- to 3-month (or occasionally longer) period—called a cluster period—which is followed by a headache-free interval of several months, or even years, before attacks begin again. Alcohol may trigger headaches during a cluster period, but not during the headache-free interval. Some people do not have a headache-free interval. They have chronic cluster headaches.

Diagnosis of Cluster Headaches

  • A doctor's evaluation
  • Sometimes magnetic resonance imaging

Diagnosis of cluster headaches is based on the person’s description of the headache and the accompanying symptoms.

If the headaches have developed recently or if the pattern of symptoms has changed, magnetic resonance imaging (MRI) of the head may be done to exclude other causes.

Treatment of Cluster Headaches

  • Oxygen or a drug to stop headaches as they start
  • Drugs to prevent cluster headaches over the long term

Stopping cluster headaches as soon as they start

The following may be used to stop (abort) a cluster headache as it is starting or to keep it from progressing:

  • Oxygen given by face mask
  • A triptan or dihydroergotamine given by injection (see table Some Drugs Used to Treat Migraines)
  • Zolmitriptan (a type of triptan) or a local anesthetic (such as lidocaine) taken by nasal spray

Cluster headaches can also be aborted by stimulating the vagus nerve (the 10th cranial nerve), which carries electrical impulses between (to and from) the brain and various parts of the head, neck, and trunk. Vagus nerve stimulation can be done noninvasively (that is, without an incision in the skin or the insertion of an instrument into the body). To do so, people place a handheld device over the place on the neck where they can feel a pulse. This device sends a mild electrical current through the skin to activate the vagus nerve from outside the body. The current travels along the vagus nerve back to the brain and helps control the pain.

Preventing cluster headaches

Because cluster headaches are so severe, frequent, and incapacitating, people who have them are given drugs to prevent them. These drugs include

  • Prednisone, a corticosteroid given by mouth
  • A local anesthetic plus a corticosteroid given by injection into the back of the head (a procedure called a nerve block)
  • Drugs used to prevent migraines (such as divalproex, topiramate, valproate, and verapamil)
  • Lithium

Prednisone or a nerve block may be used first because they take effect more quickly. Then one of the other drugs is used for long-term prevention. A nerve block must be done in the doctor's office. The other treatments can be taken at home.

Drugs Mentioned In This Article

Generic Name Select Brand Names
dihydroergotamine D.H.E. 45, MIGRANAL
Zolmitriptan ZOMIG
topiramate TOPAMAX
Prednisone RAYOS
verapamil CALAN
lidocaine XYLOCAINE

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