Key Points
Î Cluster headache (CH) is a rare and disabling primary headache disorder.
Î CH attacks are unilateral, short, severe headaches associated with
ipsilateral autonomic symptoms, restlessness, or agitation that occur in a
periodic fashion.
Î The International Classification of Headache Disorders, 2nd edition, defines
CH as at least 5 severe to very severe unilateral headache attacks, lasting
15 to 180 minutes untreated.
Î Attack frequency ranges from 1 every other day to 8 per day.
Î There are 2 types of CH:
> Episodic CH occurs in series lasting weeks or months separated by remission periods
usually lasting months or years.
> Chronic CH occurs for more than 1 year without remission or with remissions lasting
less than 1 month.
> A total of 10% to 15% of patients with CH have chronic CH.
Î When patients present with a new cluster bout, it is appropriate to initiate
both acute symptomatic therapy and preventive therapy.
Cluster Headache – Symptoms
Î The symptoms of a CH include stabbing pain behind or above one eye or in
the temple, tearing of that eye, congestion in the associated nostril, pupil
changes, and eyelid drooping.
