Cluster headaches occur in cyclical patterns or clusters — which gives the condition its name. Cluster headache is one of the most painful types of headache. Cluster headache is sometimes called the "alarm clock headache" because it commonly awakens you in the middle of the night with intense pain in or around the eye on one side of your head.
Bouts of frequent attacks — known as cluster periods — may last from weeks to months, usually followed by remission periods when the headache attacks stop completely. During remission, no headaches occur for months and sometimes even years.
Fortunately, cluster headache is rare and not life-threatening. Treatments can help make cluster headache attacks shorter and less severe. In addition, preventive medications can help reduce the number of cluster headaches.
Common signs and symptoms
The pain of a cluster headache is often described as sharp, penetrating or burning. People with this condition say that the pain feels like a hot poker being stuck in the eye or that the eye is being pushed out of its socket. People with cluster headache appear restless, preferring to pace or sit and rock back and forth to soothe the attack. In contrast to people with migraine, people with cluster headache usually avoid lying down during an attack because this position seems to increase the pain.
Some migraine-like symptoms, including nausea, sensitivity to light and sound, and aura, may occur with a cluster headache, though usually on one side.
Cluster period characteristics
Most people have episodic cluster headaches, which means the cluster headaches occur for one week to a year, followed by a pain-free remission period that may last as long as six to 12 months before another cluster headache develops. Chronic cluster periods may continue for more than a year, or pain-free periods may last less than one month.
During a cluster period:
The pain usually ends as suddenly as it begins, with rapidly decreasing intensity. After attacks, most people are completely free from pain, but exhausted.
When to see a doctor
Seek emergency care if you have any of these signs and symptoms:
The exact cause of cluster headaches is unknown, but abnormalities in the hypothalamus likely play a role. Cluster attacks typically occur with clocklike regularity during a 24-hour day, and the cycle of cluster periods often follows the seasons of the year. These patterns suggest that the body's biological clock is involved. In humans, the biological clock is located in the hypothalamus, which lies deep in the center of your brain. Abnormalities of the hypothalamus may explain the timing and cyclical nature of cluster headache. Studies have detected increased activity in the hypothalamus during the course of a cluster headache.
Unlike migraine and tension headache, cluster headache generally isn't associated with triggers, such as foods, hormonal changes or stress. But once a cluster period begins, consumption of any alcohol can quickly trigger a splitting headache. For this reason, many people with cluster headache avoid alcohol for the duration of a cluster period. Other possible triggers include the use of medications such as nitroglycerin, a drug used to treat heart disease.
Risk factors for cluster headaches include:
Preparing for your appointment
You're likely to start by seeing your family doctor. However, you may be referred to a neurologist, a doctor who specializes in treating nervous system disorders, such as headache.
Because appointments can be brief, and there's often a lot of ground to cover, it's a good idea to be well prepared for your appointment. Here's some information to help you get ready for your appointment, as well as what to expect from your doctor.
Keep a headache diary
Your time with your doctor is limited, so preparing a list of questions may help you make the most of your time together. List your questions from most important to least important in case time runs out. For cluster headaches, some basic questions to ask your doctor include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment.
What to expect from your doctor
Tests and diagnosis
Cluster headache has a characteristic type of pain and pattern of attacks. A diagnosis depends on your description of the attacks, including your pain, the location and severity of your headaches, and associated symptoms. The frequency and duration of your headaches also are important factors.
If you have chronic or recurrent headaches, your doctor may try to pinpoint the type and cause of your headache using certain approaches.
Treatments and drugs
There's no cure for cluster headaches. The goal of treatment is to help decrease the severity of pain, shorten the headache period and prevent the attacks.
Because the pain of a cluster headache comes on suddenly and may subside within a short time, over-the-counter pain relievers such as aspirin or ibuprofen (Advil, Motrin, others) aren't effective. The headache is usually gone before the drug starts working. Fortunately, other types of acute medication can provide some pain relief. Based on the latest studies, the therapies listed below have proved to be most effective for acute and preventive treatment of cluster headache.
Other preventive medications used for cluster headache include anti-seizure medications such as divalproex (Depakote) and topiramate (Topamax).
Surgical procedures for cluster headache attempt to damage the nerve pathways thought to be responsible for pain, most commonly the trigeminal nerve that serves the area behind and around your eye. The long-term benefits of surgery are disputed, however, and because of the possible complications — including muscle weakness in your jaw or sensory loss in certain areas of your face and head — it's rarely considered.
Similar research is under way using an implanted stimulator in the hypothalamus, the area of the brain associated with the timing of cluster periods. Deep brain stimulation of the hypothalamus may provide relief for people with severe, chronic cluster headaches.
Lifestyle and home remedies
The following measures may help you avoid a cluster attack during a cluster cycle:
Because cluster headaches can be so painful, you may be tempted to try alternative or complementary therapies to relieve your pain. A recent survey of people with cluster headache who tried a number of alternative therapies — including acupuncture, acupressure, therapeutic touch, chiropractic and homeopathy — found that fewer than 10 percent found these therapies effective.
Some natural medicines may be worth a try, however. In one study, kudzu extract was shown to alleviate the intensity, frequency and duration of cluster headache attacks, though it didn't decrease the length of the cluster cycle. Melatonin also has shown modest effectiveness in treating nighttime attacks. Capsicum, also known as capsaicin or cayenne, may decrease the frequency and severity of cluster headache attacks when used as a nasal spray on the affected side of your head.
Coping and support
Living with cluster headache can be very difficult. Cluster headaches can be frightening to you and to your family and friends. The debilitating attacks may seem unbearable. In addition to the physical symptoms, the chronic pain that often accompanies cluster headache attacks can make you anxious or depressed. Ultimately, it may affect your interaction with friends and family, your productivity at work, and the overall quality of your life.
Talking to a counselor or therapist can help you cope with the effects of cluster headache. Or you may find encouragement and understanding in a headache support group. Although support groups aren't for everyone, they can be good sources of information. Group members often know about the latest treatments and tend to share their own experiences. If you're interested, your doctor may be able to recommend a group in your area.
Because the cause of cluster headache is unknown, you can't prevent a first occurrence. However, a preventive strategy is crucial for managing cluster headache because trying to treat it with only acute drugs can seem hopeless. Prevention can help reduce the frequency and severity of the attacks and the risk of rebound headaches. Preventive medications can also increase the effectiveness of acute medications.
In addition, you may help reduce your risk of future attacks by avoiding alcohol and nicotine, which often precipitate cluster headaches.
Last Updated: 2011-02-08
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