The pain usually starts near one eye and shoots up to the top of the head on that side. They may also come and go for several days, weeks, or months. Each headache can last from 15 minutes to 2 hours.
Cluster headaches occur most often in the spring and fall.
They are more common among men than among women. The cause is not known. The headaches are typically sudden and severe, and may be accompanied by watery eyes or a runny nose. You may feel sweaty, restless, or nauseated. The headaches often start at night and may wake you up.