A cluster headache is one-sided head pain that may involve tearing of the eyes and a stuffy nose. Attacks occur regularly for 1 week to 1 year, separated by long pain-free periods that last at least 1 month, possibly longer.
Cluster headaches are a fairly common form of chronic, repeated headaches. They are more common in men than women. The headaches can occur at any age but are most common in adolescence and middle age. The tend to run in families.
Scientists do not know exactly what causes cluster headaches, but they appear to be related to the body's sudden release of histamine or serotonin.
The following may trigger cluster attacks:
- Alcohol and cigarette smoking
- High altitudes (trekking, air travel)
- Bright light (including sunlight)
- Heat (hot weather, hot baths)
- Foods high in nitrites (such as bacon and preserved meats)
- Certain medications
A cluster headache begins as a severe, sudden headache. The headache most commonly strikes 2 to 3 hours after falling asleep, usually during the dreaming (rapid eye movement, or REM) phase. However, the headache may occur while you are awake. The headache tends to occur at the same time of day.
The pain occurs on one side of the head. It may be described as:
The pain may occur in, behind, and around one eye. It may:
- Involve one side of the face from neck to temples
- Quickly gets worse, peaking within 5 to 10 minutes
- The strongest pain may last 30 minutes to 2 hours.
The eye and nose on the same side of the head pain may also be affected. Symptoms can include:
- Swelling under or around the eye (may affect both eyes)
- Excessive tearing
- Red eye
- Rhinorrhea (runny nose) or one-sided stuffy nose (same side as the head pain)
- Red, flushed face
Cluster headaches may occur daily for months, alternating with periods without headaches (episodic), or they can recur for a year or more without stopping (chronic).
Exams and Tests
Your health care provider can diagnosis this type of headache by performing a physical exam and asking questions about your symptoms and medical history.
If a physical exam is done during an attack, the exam will usually reveal Horner syndrome (one-sided eyelid drooping or a small pupil). These symptoms will not be present at other times. No other neurological changes will be seen.
Tests, such as an MRI of the head, may be needed to rule out other causes for the headaches.
Treatment does not cure cluster headaches. The goal of treatment is to relieve symptoms. The headaches may go away on their own, or you may need treatment to prevent them.
Smoking, alcohol use, specific foods, and other factors that seem to trigger cluster headaches should be avoided. A headache diary can help you identify your headache triggers. When you get a headache, write down the day and time the pain began. The diary should include notes about what you ate and drank in the last 24 hours, how much you slept and when, and what was going on in your life immediately before the pain started. For example, were you under any unusual stress? Also include information about how long the headache lasted, and what made it stop.
Treatment for cluster headaches involves:
- Methods to treat the pain when it happens
- Medicines to prevent the headaches
Your doctor may recommend the following treatments for when the headaches occurs:
- Triptans, such as sumatriptan (Imitrex)
- Several weeks of anti-inflammatory (steroid) medicines such as prednisone -- starting with a high dose, then gradually decreased
- Breathing in 100% (pure) oxygen, often relieves cluster headache for some people, particularly for frequent cluster headaches that occur at night
- Injections of the drug known as dihydroergotamine (DHE), which can stop cluster attacks within 5 minute (Warning: this drug can be dangerous if taken with sumatriptan)
A combination of medicines may be needed to control headache symptoms. Because each person responds differently to medicine, your doctor may have you try several medications before deciding which works best for you.
Painkillers do not usually relieve the pain from cluster headaches. Generally, they take too long to work.
The following medications may also be used to treat or prevent headache symptoms:
- Antiseizure medications such as topiramate and valproic acid
- Indomethacin or naproxen
- Lithium carbonate
- Calcium channel blockers such as verapamil
In rare cases, surgery on certain nerve cells near the brain may be recommended if medications do not work.
Cluster headaches are not life-threatening and usually cause no permanent structural changes. However, they are chronic and often painful enough to interfere with work or lifestyle. Occasionally, the pain may be so severe that some people may consider self harm.
Side effects of medications or surgery may be severe.
- Headaches that interfere with daily activities
- Horner syndrome
- Side effects of medications
- Complications due to surgery to treat the headaches, including:
- Permanent muscle weakness in the face or head
- Decreased sensation in parts of the face or head
When to Contact a Medical Professional
Call for an appointment with your health care provider if cluster headaches do not respond to treatment, if headaches disturb sleep, if they happen whenever you are active, or are accompanied by other symptoms.
Emergency symptoms include drowsiness, vision changes, changes in movement or sensation, seizures, changes in alertness, and nausea or vomiting.
If prone to cluster headache, stop smoking. Alcohol use and any foods that are associated with cluster headache may need to be avoided. Medications may prevent cluster headaches in some cases.