Cluster Headache Attack Characteristics
Cluster headache attacks are characterized by severe, strictly unilateral pain in the orbital, supraorbital, or temporal region lasting 15-180 minutes, accompanied by ipsilateral cranial autonomic symptoms and restlessness or agitation. 1
Pain Characteristics
The headache pain is:
- Severe to very severe intensity - described by female patients as worse than childbirth 2
- Strictly unilateral location (orbital, supraorbital, and/or temporal regions) 3
- Duration: 15-180 minutes when untreated 3, 2
- Not throbbing (unlike migraine) - the pain quality is distinct from the pulsating character of migraine
Ipsilateral Autonomic Symptoms
At least one of the following must occur on the same side as the pain 3:
- Lacrimation (tearing) - most common
- Conjunctival injection (red eye) - most common 1
- Nasal congestion
- Rhinorrhea (runny nose)
- Forehead and/or facial sweating
- Ptosis (drooping eyelid)
- Miosis (pupil constriction)
- Eyelid edema
Attack Frequency and Pattern
- Frequency: 1-8 attacks per day during active periods 3
- Attacks occur in "clusters" or "bouts" lasting weeks to months 4
- At least 5 attacks are required for diagnosis 3
- Attacks can occur every other day up to 8 times daily 4
Distinguishing Feature: Restlessness
Unlike migraine patients who prefer to lie still in a dark room, cluster headache patients exhibit marked restlessness and agitation during attacks 5. This is a critical diagnostic feature that separates cluster headache from migraine.
Common Pitfalls
Do not confuse with migraine: While both are severe unilateral headaches, cluster headache is:
- Much shorter (15-180 min vs 4-72 hours for migraine)
- Associated with prominent autonomic symptoms (not just photophobia/phonophobia)
- Accompanied by restlessness (not desire to lie still)
- More frequent during active periods (multiple daily vs occasional)
Gender considerations: While historically male-predominant (2-3:1 ratio), recent data shows decreasing male-to-female ratios 4, 6. Women with cluster headache may report longer, more severe attacks with more migrainous symptoms and are more often misdiagnosed as having migraine 7.
Triggers
Common triggers include 4:
- Alcohol (during active cluster periods)
- Nitroglycerin
- Foods containing nitrates
- Strong odors
Critical note: The severity of cluster headache attacks leads to suicidal ideation in over 40% of patients 8, making prompt recognition and aggressive treatment essential for patient safety.