Diagnostic Criteria for Cluster Headache

1. Diagnostic Criteria for Cluster Headache
(1) At least 5 attacks fulfilling criteria 2-4. (2) Severe or very severe unilateral orbital, supraorbital, and/or temporal pain lasting 15-180 minutes if untreated¹. (3) Headache is accompanied by at least one of the following: ① Ipsilateral conjunctival injection and/or lacrimation; ② Ipsilateral nasal congestion and/or rhinorrhea; ③ Ipsilateral eyelid edema; ④ Ipsilateral forehead and facial sweating; ⑤ Ipsilateral miosis and/or ptosis; ⑥ Restlessness or agitation. (4) Attack frequency ranges from one every other day to 8 per day². (5) Not attributed to another disorder. Note 1: In less than half of the patients, the pain intensity may be less severe, and the duration may be shorter or longer than the criteria. Note 2: In less than half of the patients, the attack frequency may be lower than the criteria.
2. Diagnostic Criteria for Episodic Cluster Headache
(1) Attacks fulfilling criteria 1-5 of cluster headache. (2) At least two cluster periods lasting 7-365 days and separated by pain-free remission periods of ≥1 month.
3. Diagnostic Criteria for Chronic Cluster Headache
(1) Attacks fulfilling criteria 1-5 of cluster headache. (2) Attacks recur for more than 1 year without remission periods, or with remission periods lasting <1 month.