A cluster headache is really very rare, although it can be quite a frightening experience. It seems to affect men more than women and unlike migraine, it does not seem to run in families.
Usually a cluster headache starts with a very sharp pain in one eye or one side of the face. The pain is intense and continuous as opposed to throbbing. The eye which is affected (or the eye on the side of the face wihich is affected) fills with tears, the nose blocks on the affected side and then starts to run. The cheek may also swell up. Often the headache happens during the night.
Cluster headaches may occur a few times a day for weeks or months and then disappear for a few months, then re-appear again for no known reason. Prescription medicines are available for this condition and this type of headache usually requires medical attention.