What is a cluster headache?
Cluster headaches are rare when compared with other types of headaches. The pain they
cause is severe and tends to recur in the same way each time. They occur in groups,
or clusters. Each attack lasts about 1 to 3 hours on average. They may occur every
other day, up to multiple times a day. Cluster periods are followed by remissions
where there are no headaches. These may last months or years.
Men are affected by cluster headaches more than women. The headaches typically start around
What causes cluster headaches?
Researchers don't know exactly what causes cluster headaches. They seem to be related
to the sudden release of histamine or serotonin in the body.
The following may trigger cluster headaches:
Alcohol use or smoking cigarettes
Change to a high altitude
Exercise or exertion
Heat, from either the weather or a bath
Foods that contain nitrates, such as bacon or lunch meat
What are the symptoms of cluster headaches?
These are common symptoms of a cluster headache:
Sudden onset of pain, generally around or behind the eye
Pain builds to a peak in about 10 to 15 minutes
Restlessness or agitation
Red or watering eyes
Sweating on the forehead
Eyelid drooping or swelling
Changes in the pupil of the eye during a cluster headache
The symptoms of a cluster headache may look like other health conditions. Always see
your healthcare provider for a diagnosis.
How are cluster headaches diagnosed?
Your healthcare provider will diagnose cluster headaches based on your history of
a pattern of near-daily headaches that come back again and again for days, weeks,
How are cluster headaches treated?
A two-pronged approach is used for treatment of cluster headaches:
To stop or at least control an attack in progress, you may be given high-dose oxygen
therapy through a face mask for 15 to 20 minutes. Your healthcare provider may also
prescribe an injection called sumatriptan to ease the severe pain of a cluster headache.
Sumatriptan is a selective serotonin receptor agonist. This medicine causes blood
vessels in the brain to constrict. This eases pain. Other triptans may also be tried
if sumatriptan doesn’t help.
The second part of cluster headache treatment is to prevent recurrent attacks by using
daily medicine. Several medicines are used to prevent cluster headache attacks:
Verapamil. A medicine that relaxes blood vessels.
Prednisone. A steroid that reduces inflammation and swelling.
Lithium carbonate. A medicine that restores the balance of certain brain chemicals.
Anti-seizure medicines. Medicines that may help reduce the number of cluster headaches.
Galcanezumab. This is a newer medicine.
What are possible complications of cluster headaches?
A true cluster headache is not life-threatening. It does not cause permanent brain
damage. But they tend to be long-term (chronic) and recurrent. They can interfere
with your lifestyle or work.
Can cluster headaches be prevented?
To prevent a cluster headache, it’s important to find out what triggers your headaches.
Try not smoking and using alcohol. Keep a journal that describes what you were doing,
eating, or drinking when the headache started. Bring the journal to your appointments.
The journal information may help your healthcare provider prescribe a medicine and
a management plan that will help prevent cluster headaches.
When should I call my healthcare provider?
Some danger signs may occur with cluster headaches that mean you should get medical
care right away. These include:
Key points about cluster headaches
Cluster headaches occur in groups, or clusters, and each attack lasts about 1 to 3
hours on average.
They may occur every other day to multiple times a day.
Cluster periods are followed by remissions that may last months or years.
Compared with other types of primary headaches, cluster headaches are rare.
The pain they cause is severe, and they tend to recur in the same way each time
Finding out headache triggers may help prevent their occurrence.
A true cluster headache is not life-threatening and does not cause permanent brain
Tips to help you get the most from a visit to your healthcare provider:
Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember what your provider tells
At the visit, write down the name of a new diagnosis, and any new medicines, treatments,
or tests. Also write down any new instructions your provider gives you.
Know why a new medicine or treatment is prescribed, and how it will help you. Also
know what the side effects are.
Ask if your condition can be treated in other ways.
Know why a test or procedure is recommended and what the results could mean.
Know what to expect if you do not take the medicine or have the test or procedure.
If you have a follow-up appointment, write down the date, time, and purpose for that
Know how you can contact your healthcare provider if you have questions.