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HeadWay, Issue #046 -- Cluster headache
May 22, 2007

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In this month's issue:

Headache classification part 3 - Cluster headache

Popular topic revisited - eye migraines

Say what?! Multifactorial

Headache classification part 3 - Cluster headache

Today in part 3 of our articles on headache classification we're going to talk about cluster headache. Cluster, although one of the worst on the list, is little understood by the general public because it is fairly rare. Most people have their first attack between the ages of 20 and 40. Unlike migraine, which attacks more women than men, cluster is 3-4 times more prevalent in men.

Cluster has gone by many other names, including Horton's Headache, ciliary neuralgia, erythro-melalgia of the head, and Harris-Horton's disease. Although it's now commonly called cluster headache, there is some evidence that, like migraine, the headache is only one possible symptom. In other words, you could have other symptoms without headache at all. However, for the most part it is still diagnosed as a headache, and probably will continue to be unless we soon learn more about what exactly causes it. Still, you'll sometimes see me use the term cluster instead of cluster headache.

Symptoms of cluster

Why are they called "clusters"? Because you get a cluster of attacks for a period of time. Then you may go for months or years with no attacks at all, then once again - several attacks a day for a while. It has nothing to do with where the pain is. Cluster periods usually last between 2 weeks and 3 months.

To be diagnosed with cluster you need to have 5 attacks, lasting 15 minutes to 3 hours, from every other day to 8 times a day. Also, you need a headache and at least one of the following symptoms (rather than using exact terms, I'm putting these in more general plain English descriptions. For more specifics, see the document The International Classification of Headache Disorders). All of these (except the last) are only on one side of the body:
  • Swollen, red eye or teary eye
  • Congestion/runny nose
  • Swollen eyelid
  • Forehead/facial sweating
  • Upper eyelid drooping, small pupil
  • A restless and agitated feeling

  • Cluster headache is one of the most painful headaches, and combined with these other strange symptoms and the feeling of agitation, patients feel like they're going crazy.

    Currently Wikipedia on cluster headache describes the pain like this:

    Persons who have experienced both cluster headaches and other painful conditions (childbirth, migraines) report that the pain of cluster headaches is far worse, significantly more severe than a migraine. The pain has been described as akin to being stabbed repeatedly in the eye with an ice pick or hot poker. It has been described in medical journals as one of the most severe pain syndromes suffered by human beings.

    Note also that we're mainly talking about episodic cluster headache. Chronic cluster headache continues for a year or more, with a month or less of remission.

    Cause of cluster

    Like migraine, we don't understand what causes cluster. Science is giving more and more clues. Because of the "rhythms" of cluster, it seems that the attacks are somehow tied to the rhythms of the body. It's also believed that the answers may lie in the nervous system, particularly in the hypothalamic region. Read more about the cause of cluster headache. We also know that there are things that can make attacks worse or trigger attacks, such as alcohol, napping, or exposure to perfumes. However, eliminating triggers is not a simple "cure" for cluster. It can only minimize the symptoms or delay an attack in a few people.

    Treatment of cluster

    There are two goals when treating cluster - stop an attack from coming, and ease the suffering during an attack.

    Some acute treatments (during an attack) include inhaling oxygen, local anaesthetics, and some medication familiar to migraine patients such as Sumatriptan and ergot derivatives. Preventatives include drugs such as verapamil (and other calcium channel blockers), methysergide and divalproex sodium (Depakote). In some cases where medication doesn't help or can't be tolerated, the patient may have surgery to actually destroy a part of the trigeminal nerve. Read more about treatment of cluster. Other treatments are being investigated, such as deep brain stimulation and other medications, including controversial indole-ring hallucinogens.

    This is only the briefest introduction. has a great one-page summary of cluster headache and its treatments here. The Mayo Clinic's article on cluster headache starts here. Justin Douglas Ott, a cluster headache sufferer, is working on a documentary on cluster headache. Also, I wrote an article similar to this one in HeadWay before - read Focus on Cluster.

    Popular topic revisited - eye migraines

    There are actually a number of headache-related diseases that can do strange things to the eyes. Cluster is one of those, a common symptom being teary eyes or drooping eyelids on one side.

    The term eye migraine has been used to describe a number of different issues, some not migraines at all, that cause visual disturbances, blindness, or weakness in the eye muscles.

    For a quick summary of things that have been called eye migraines, read this article.

    Research has recently pointed to the fact that some headache and migraine sufferers are more prone to retina disease. Read more about headache and retinopathy. Finally, if you have sore eyes or photophobia (sensitivity to light), here are some ideas for making computer use more bearable.

    Say what?! Multifactorial

    I don't think I've used this word here before, and yet it's one of the most important words and concepts to understand. If you want to get successful treatment, you almost always have to understand this one.

    Multifactorial (or multi factorial) simply means that your symptoms are coming from a variety of causes. For example, let's say you have chronic headaches. Your doctor discovers that you have neck and shoulder problems, and you go for therapy. But you still have the headaches. Why? Wasn't that the cause?

    It probably was a cause. But often headaches are multifactorial - they have a number of causes. This makes treatment difficult, because you may need to do a number of things before the problem goes away. You may need to improve your eating habits, go to physiotherapy and take medication. No one thing may solve the problem, but all three things may.

    Just because the headaches don't go away doesn't mean you're not on the right track. Don't give up.
    Have a comment?  A suggestion for a future topic?  Drop by the HeadWay MailRoom and use your password, nomoache!
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