Cluster headaches are severe headaches on one side of your head that happen in groups, or "clusters." They usually occur over weeks or months.
Cluster headaches can be so painful that you are not able to follow your normal routine or do your usual activities. The pain is often called the worst type of headache pain.
Cluster headaches come in cycles (also called cluster periods). Most people who get cluster headaches have one or two cluster periods each year. A cluster period might last 1 month or longer. After a cluster period ends, you may not get another headache for months or even years.
As you get older, it's likely that you'll have longer and longer times without headaches. At some point, you may not get cluster headaches ever again.
Having cluster headaches can be scary. But even though they are very painful, cluster headaches don't cause long-term harm. During a cycle, you may be able to reduce how often you have them, how bad they are, and how long they last.
What causes cluster headaches?
Experts aren't sure what causes cluster headaches. They run in families, but it's not clear why some people get cluster headaches and others don't.
What are the symptoms?
The main symptom of cluster headaches is a severe burning or sharp, piercing pain on one side of your head. The pain spreads out from your temple and eye. Your eye may become red, watery, or puffy. The eyelid may droop, and you may have a runny or stuffy nose on that side of your head.
The pain usually gets bad very fast. The pain gets worse within 5 to 10 minutes after the headache starts and can last for 15 minutes or longer.
Cluster headaches usually happen at the same time of day each time you get them. But they can happen at any time. You may have 1 to 8 headaches a day.
How are cluster headaches diagnosed?
A doctor can usually tell if you have cluster headaches by asking about your symptoms and examining you. Your doctor may order other tests, such as a CT scan or an MRI, if he or she thinks your symptoms are caused by another disease. But most people won't need these tests.
How are they treated during a cycle?
When a headache starts, you can take medicine or breathe in oxygen from a machine to ease the pain or stop the headache. You use these treatments only when you feel a headache coming on. You don't use them every day.
When a cluster headache begins:
Start your treatment right away. Don't wait for the headache to get worse. Take your medicine exactly as planned with your doctor.
Do what feels best. You may feel better if you walk, jog in place, sit, kneel, or stand. Lying down may make the pain worse.
If your treatment doesn't work, ask your doctor if you can try something else. It may take time to find what works best for you.
Over-the-counter pain medicines, such as aspirin, acetaminophen, and ibuprofen, usually don't work for cluster headaches.
Dealing with repeated cluster headaches can lead to stress and depression, which in turn can continue the headache cycle. Finding ways to cope with stress (such as with regular exercise) and improve depression may reduce the severity or frequency of your cluster headaches.
How are cluster headaches prevented?
There is no cure for cluster headaches. You can't do anything to prevent a cycle of cluster headaches from starting.
But as soon as a cycle starts, you can take medicine that may help prevent more headaches or reduce how many you have during a cycle. You take this medicine every day during the cycle.
Certain things may be more likely to cause a headache during a cycle. These are called triggers. Avoiding them may help prevent headaches. Triggers include:
Sleep problems. It's best if you go to bed and wake up at the same time every day. Don't take naps.
Increases in body temperature. This can happen when you exercise, take a hot bath, or get angry.
Nitrates. These are found in wine, cured meats, aged cheeses, and some medicines.
Histamine. Seasonal allergies could trigger a headache.
A headache diary( What is a PDF document? ) can give you and your doctor clues to help you manage your headaches. Write down when and how often the headaches happen, how severe they are, and what you think may be causing them. Share this with your doctor.
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ByHealthwise StaffPrimary Medical ReviewerAnne C. Poinier, MD - Internal MedicineE. Gregory Thompson, MD - Internal MedicineAdam Husney, MD - Family MedicineMartin J. Gabica, MD - Family MedicineKathleen Romito, MD - Family MedicineSpecialist Medical ReviewerKarin M. Lindholm, DO - Neurology