Cluster headache.

Cluster headache is a relatively rare episodic headache disorder.Although traditionally it is believed to be a male-related disorder,the sex ratios are changing toward a more even balance. The disorder is characterized by bouts of daily headaches with pain-free remissions for extended times. Though attacks are brief, they are severe and typically are associated with autonomic symptoms. Medical therapies are the mainstay of treatment, with the goal being prevention of headaches in a cycle. Acute therapies, although effective, may be limited in usefulness because of attack frequency. Intractable cases may benefit from histamine desensitization and surgical treatments.