What are cluster headaches?
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
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.
See a picture of
cluster headache symptoms .
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
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
- 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
Dealing with repeated cluster
headaches can lead to
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
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
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:
- Drinking alcohol.
- 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.
Health Tools help you make wise health decisions or take action to improve your health.
Decision Points focus on key medical care decisions that are important to many health problems.
- Headaches: Should I Have Imaging Tests to Find Out What's Causing My Headaches?
Learning about cluster headaches:
What are cluster headaches?
Who is affected by cluster headaches?
Are there different types of cluster headaches?
What other conditions are like cluster headaches?
What will happen during a physical exam for my headaches?
Do I need imaging tests to evaluate my headaches?
Will I need other tests to evaluate my headaches?
What medicines will I need to take?
What is a headache clinic?
National Headache Foundation (NHF) (U.S.)
Other Works Consulted
Diamond S (2009). Cluster headaches. In Diagnosing and Managing Headaches, 7th ed., pp. 121–136. West Islip, NY: Professional Communications.
Francis GJ, et al. (2010). Acute and preventative pharmacologic treatment of cluster headache. Neurology, 75(5): 463–473.
Green MW (2010). Primary and secondary headaches. In LP Rowland, TA Pedley, eds., Merritt's Neurology, 12th ed., pp. 951–960. Philadelphia:
Lippincott Williams and Wilkins.
Matharu M (2010). Cluster headache, search date June 2009. Online version of BMJ Clinical Evidence: http://www.clincalevidence.com.