A. Cluster Headaches come in at least 2 varieties.
The "typical cluster headache" is the most common, and consists of 1 to 3 attacks of pain per day, for a 4 to 8 week period, followed by months to years of pain-free time (i.e. a "cluster" of headaches). It's onset is sudden, usually beginning with pain at one temple, and peaks in intensity after 5 minutes. It is a deep, non-throbbing, extremely severe pain which centres around one eye and may be acompanied by tearing, red eye, eyelid droop and nasal stuffiness. They usually last 30 minutes.
Interestingly, 85% of patients note a periodicity of attacks, to the point of being able to predict their daily onsets to the hour!!!
What brings them on and why remains mostly a mystery, although theories about circulation problems and the involvement of serotonin abound. One thing for sure is that alcohol can bring on attacks during the "cluster" time, although it doesn't do so during "remission" times. Rarely, foods and emotional factors can also provoke attacks.
The best treatment is prevention of headache, and a number of useful medications exist. Accurate diagnosis and close follow-up with your family doctor should ensure good control.
P.S. As for the second variety of cluster headache, it's a chronic form of the same problem, with no intervals of pain free time. Just the thought of this makes me cringe!
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