Cluster Headaches Cluster headaches are an extremely painful but uncommon type of migraine headache. Cluster headaches affect mostly men over 30 years old. An attack almost always starts suddenly and ends within an hour. It often starts with itching or watery discharge from one nostril that proceeds to intense pain on that side of the head and spreads around the eye. After the attack, the eyelid on the same side may droop, and the pupil often constricts.
Attacks come in groups, ranging from two attacks a week to several a day.
Most episodes of cluster headaches last for 6 to 8 weeks, and occasionally longer, followed by headache-free intervals of several months before the episodes recur.