Cluster headache |
 A. At least 5 attacks fulfilling criteria B-D |
 B. Severe or very severe unilateral orbital, supraorbital and/or temporal pain lasting 15–180 min if untreated |
 C. Headache is accompanied by at least one of the following: |
  1. Ipsilateral conjunctival injection and/or lacrimation |
  2. Ipsilateral nasal congestion and/or rhinorrhoea |
  3. Ipsilateral eyelid oedema |
  4. Ipsilateral forehead and facial sweating |
  5. Ipsilateral miosis and/or ptosis |
  6. A sense of restlessness or agitation |
 D. Attacks have a frequency from one every other day to 8 per day |
 E. Not attributed to another disorder |
Episodic cluster headache |
 A. Diagnostic criteria A-E for cluster headache |
 B. At least two cluster periods lasting 7–365 days and separated by pain-free remission periods of ≥ 1 month |
Chronic cluster headache |
 A. Diagnostic criteria A-E for cluster headache |
 B. Attacks recur over > 1 year without remission periods or with remission periods lasting < 1 month. |