Cluster headache

International Classification of Headache Disorders-3 (ICHD-3)[2]Headache Classification Committee of the International Headache Society (IHS). The International Classification of Headache Disorders, 3rd edition. Cephalalgia. 2018 Jan;38(1):1-211. https://journals.sagepub.com/doi/10.1177/0333102417738202 http://www.ncbi.nlm.nih.gov/pubmed/29368949?tool=bestpractice.com

Cluster headache

• A. At least 5 attacks fulfilling criteria B to E.

• B. Severe or very severe unilateral orbital, supraorbital, and/or temporal pain lasting 15 to 180 minutes (when untreated).

• C. Either or both of the following:

  • At least one of the following symptoms or signs, ipsilateral to the headache:

    • Conjunctival injection and/or lacrimation

    • Nasal congestion and/or rhinorrhea

    • Eyelid edema

    • Facial and forehead sweating

    • Miosis and/or ptosis

  • A sense of restlessness or agitation.

• D. Occurring with a frequency between 1 every other day and 8 per day.

• E. Not better accounted for by another ICHD-3 disorder.

Episodic cluster headache

• Attacks fulfilling criteria for cluster headache (above) and occuring in bouts (cluster periods)

• At least 2 cluster periods lasting 7 days to 1 year (when untreated) and separated by pain-free remission periods lasting ≥3 months.

Chronic cluster headache

• Attacks fulfilling criteria for cluster headache (above)

• Occurring without a remission period, or with remission lasting <3 months, for at least 1 year.