The cluster headache and its treatment

1. Big picture

Cluster headache is a primary headache and the most important member of the trigeminal autonomic cephalalgias. It is rare compared with migraine and tension-type headache, but it is one of the most painful conditions in neurology.

The key exam idea:

Cluster headache = strictly unilateral orbital/temporal excruciating pain + ipsilateral autonomic signs + short attacks + circadian/circannual periodicity.

The patient is typically restless, walks around, may press or hit the head, and cannot lie quietly. This is the opposite of migraine, where the patient usually wants to lie still in a dark room.