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IHS Diagnosis ICD-10
3.2 Paroxysmal hemicrania G44.03  


Attacks with similar characteristics of pain and associated symptoms and signs to those of cluster headache, but they are shorter-lasting, more frequent, occur more commonly in females and respond absolutely to indomethacin.

Diagnostic criteria:

  1. At least 20 attacks fulfilling criteria B-D
  2. Attacks of severe unilateral orbital, supraorbital or temporal pain lasting 2-30 minutes
  3. Headache is accompanied by at least one of the following:
    1. ipsilateral conjunctival injection and/or lacrimation
    2. ipsilateral nasal congestion and/or rhinorrhoea
    3. ipsilateral eyelid oedema
    4. ipsilateral forehead and facial sweating
    5. ipsilateral miosis and/or ptosis
  4. Attacks have a frequency above 5 per day for more than half of the time, although periods with lower frequency may occur
  5. Attacks are prevented completely by therapeutic doses of indomethacin1
  6. Not attributed to another disorder2


  1. In order to rule out incomplete response, indomethacin should be used in a dose of ≥150 mg daily orally or rectally, or ≥100 mg by injection, but for maintenance smaller doses are often sufficient.
  2. History and physical and neurological examinations do not suggest any of the disorders listed in groups 5-12, or history and/or physical and/or neurological examinations do suggest such disorder but it is ruled out by appropriate investigations, or such disorder is present but attacks do not occur for the first time in close temporal relation to the disorder.


There is no male predominance. Onset is usually in adulthood, although childhood cases are reported.

In the first edition all paroxysmal hemicranias were referred to as chronic paroxysmal hemicrania. Sufficient clinical evidence for the episodic subtype has accumulated to separate it in a manner analogous to cluster headache.

Paroxysmal hemicrania with coexistent trigeminal neuralgia (CPH-tic syndrome):

Patients who fulfil criteria for both 3.2 Paroxysmal hemicrania and 13.1 Trigeminal neuralgia should receive both diagnoses. The importance of this observation is that both conditions require treatment. The pathophysiological significance of the association is not yet clear.