Many people who suffer with migraine get several days of headache in a row and wonder if they are having clusters of headaches. It is confusing because actually cluster headache is a different type of headache condition. There are some similarities between migraine and cluster headache but there are also some significant differences. It is important to distinguish between them because there are some treatments which work more effectively for cluster headaches than for migraine.
So what is Cluster Headache?
- Agony: Sometimes called ‘suicidal headaches’ because of the excruciating intensity of the pain, they are always on one side of the head (usually on the same side) and very often behind the eye.
- Sudden: They begin very suddenly with the pain rapidly reaching distressingly high levels in a matter of minutes.
- Short: The attack often is quite short in duration lasting 15 minutes to an hour and a half (though they may last as long as 3 hours).
- Repeated attacks: Often they occur several times in a day. This pattern may repeat every day for a number of weeks or months. The attacks eventually settle and go and there is then some time without pain. This relief may last a variable amount of time before the headaches recur.
- Agitation: The pain in cluster headache is so sudden and agonising that it often makes sufferers want to bang their heads, stride about or rock. It causes great agitation. This is one of the differences from migraine attacks where the migraineur is often very sensitive to movement and is helped by keeping as still as possible.
- Time & Seasons: Another typical feature is the relationship to the time of day or the seasons. Cluster headaches often start at the same time each day or repeatedly wake sufferers at the same time each night. They may also recur at the same time of year. This pattern is not seen so typically in migraine headache. Cluster headache is more common in Autumn and Spring.
- Autonomic features: Both migraine and cluster headaches can involve the part of the nervous system called the autonomic nervous system. When this is affected, sufferers notice watering from the eye, sweating of the face and a blocked or runny nose on the affected side. Sometimes drooping and swelling of the eyelid occurs and the size of the pupil may be smaller than usual. The eye may look red too.
- Triggers: In both migraine and cluster headache it may not be possible to identify why they start. In some cluster headache sufferers though there may be some obvious triggers especially during a bout. Alcohol is a common one. Being hot after exercising, being in a stuffy room or having a hot bath can also start an attack. Many sufferers of both migraine and cluster headaches are also very sensitive to strong smells like perfume, solvents, petrol etc.
How common are Cluster Headaches?
1 in 1000 people get cluster headaches and, of these, about 10% are chronic with headachefree periods lasting less than a month. Sometimes another family member may also suffer from cluster headaches –in about 1 in 20 cases there is a positive family history. Migraine is much more common and also often runs in families. The average lifetime prevalence of migraine is about 18%.