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). Headaches usually occur regularly during a 1- to 3-month period, followed by a headache-free period of months to years.

• Excruciating pain occurs 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.

Cluster headaches are relatively rare, affecting about 1 to 4 of 1,000 people. Cluster headaches affect mostly men. They typically begin between the ages of 20 and 40. Drinking alcohol may trigger attacks.

Symptoms

An attack almost always starts suddenly. It may begin with itching of or a watery discharge from one nostril. Excruciating pain on the same side of the head follows and spreads around the eye. The pain reaches peak intensity within minutes and usually lasts 30 minutes to 1 hour. The pain often awakens people from sleep. People with cluster headaches, unlike those with a migraine, cannot lie down, frequently pace, and sometimes bang their heads.

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

Attacks may occur several times a day. They usually occur regularly during a 1- to 3-month period (cluster period), occasionally longer, followed by a headache-free period of several months or even years before they recur. They usually recur at the same time of day or night. Some people do not have a headache-free interval. They have chronic cluster headaches.

Diagnosis

Diagnosis is based on the person's description of the headache and the accompanying symptoms. If the pattern of symptoms changes, magnetic resonance imaging (MRI) of the head may be done.

Treatment

Most people with cluster headaches need to take drugs to prevent recurrences. The following may be used to stop (abort) a cluster headache as it is beginning:

• Oxygen given by face mask
• A triptan or dihydroergotamine given by injection (see Headaches: Drugs Used to Treat Migraines) Other drugs are given to prevent headaches:
• 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 topiramate, valproate, and verapamil)
• Lithium

Prednisone or the nerve block may be used first because they take effect more quickly. Then one of the other drugs is used for long-term prevention. Oxygen and injections of dihydroergotamine or a local anesthetic plus a corticosteroid must be given in the hospital. The other treatments can be taken at home.

Last full review/revision April 2008 by Stephen D. Silberstein, MD