Criteria - all of the following:
(1) average headache frequency >= 15 days per month (>= 180 days per year) for >= 6 months
(2) at least 2 of the following pain characteristics:
(2a) pressing, tightening quality
(2b) mild to moderate severity (may inhibit but not prohibit activities)
(2c) bilateral
(2d) not aggravated by walking stairs or other routine physical activity
(3) both of the following:
(3a) no vomiting
(3b) no more than one (none or one) of the following: nausea, photophobia, phonophobia
(4) one of the following:
(5a) There are no other headache disorders that could explain the findings.
(5b) If the patient is at risk for a secondary headache, then there is evidence (history, physical examination, neurologic examination) that these are not causing the cluster headache.
(5c) If the patient does have a headache secondary to another cause, then the cluster headache does not occur for the first time in close temporal relation to that disorder.
where:
• The definition for the fifth criteria refers to headaches in groups "5-11", which is based on the listing of headache conditions in the article. These are: head trauma, vascular disorder, nonvascular intracranial disorder, substance withdrawal, non-cephalic infection, metabolic disorder, and physical disorder of head and neck.
Overuse of drugs may aggravate headache. Discontinuation of daily drug intake often results in improvement.
