5-Minute Clinical Consult

Headache, Cluster

Headache, Cluster was found in 5-Minute Clinical Consult which helps you diagnose, treat, and follow up on over 900 medical conditions seen in everyday practice.

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  • Primary headache disease
  • Multiple attacks of strictly unilateral, excruciating, sharp, searing, or piercing pain, typically localized in the periorbital area and temple accompanied by signs of ipsilateral autonomic features: Severe pain syndrome
  • Autonomic symptoms: Parasympathetic hyperactivity signs (ipsilateral lacrimation, eye redness, and nasal congestion) and sympathetic hypoactivity (ipsilateral ptosis and miosis)
  • Symptoms remain on the same side during a single cluster attack. In 15% of patients, symptoms switch to the other side during a different cluster attack.
  • Attacks are without prodrome, rapidly escalating in intensity usually within 15 minutes, frequently have a circadian rhythmicity, and often wake patients 60–90 minutes after falling asleep. In contrast to other headache syndromes, the severe pain may cause patients to pace restlessly and occasionally exhibit agitated behavior.
  • Individual attacks last 15–180 minutes if untreated and occur from once every other day to 8×/d. 2 forms exist: Episodic and chronic (see “Diagnosis”)


1-year incidence: 53/100,000

  • Lifetime prevalence 124/100,000 (~0.1%)
  • Predominant sex: Male > Female (4.3:1)
  • Mean age of onset: Between 29.6 and 35.7 years
  • Episodic cluster headaches (CH) > chronic CH

Risk Factors

  • Male gender
  • Age 30–60 years
  • Cigarette smoking
  • Family history of CH
  • Alcohol induces attacks during a cluster, but not during remission.
  • Small amounts of vasodilators (e.g., alcohol, nitroglycerine, sildenafil)
  • Strong odors
  • Usually sporadic. Autosomal-dominant in ~5% of cases, autosomal–recessive or multifactorial in other families
  • 1st-degree relatives carry 5–8-fold; 2nd-degree 1–3-fold increased relative risk of disease.


  • Complex and incompletely understood
  • Proposed mechanisms include:
    • Pain: Activation of trigeminal nerve
    • Autonomic symptoms: Activation of craniofacial parasympathetic nerve fibers secondary to pathologic activation of trigemino-autonomic brain stem reflex. Posterior hypothalamus, which shows strong activation signal in functional imaging studies, may trigger and control the cycling aspects of the pain.



Commonly Associated Conditions

  • Increased risk of suicide secondary to the extreme nature of the pain
  • Medication-overuse headache
  • History of migraine, frequently in female patients
  • Sleep apnea
  • Increased prevalence of cardiac right-to-left shunt and patent foramen ovale

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