What are the symptoms and treatment options for paroxysmal hemicrania?

Paroxysmal Hemicrania Symptoms

Paroxysmal hemicrania is characterized by severe, strictly unilateral headache attacks lasting 2-30 minutes with ipsilateral cranial autonomic features, occurring multiple times daily, and showing an absolute response to indomethacin.

Clinical Presentation

Core Symptoms

• Pain Characteristics:

  • Strictly unilateral pain (typically orbital, temporal, and frontal)
  • Severe intensity
  • Short-lasting attacks (mean duration of 17 minutes)
  • High frequency (mean of 11 attacks per day, typically >5 daily)
  • Rapid onset and cessation

• Cranial Autonomic Features (ipsilateral to pain):

  • Lacrimation (87% of patients) 1
  • Conjunctival injection (68%) 1
  • Rhinorrhea (58%) 1
  • Nasal congestion (54%) 1
  • Ptosis (54%) 1
  • Facial flushing (54%) 1
  • Less common: eyelid edema, forehead/facial sweating, aural fullness, miosis/mydriasis 1

• Behavioral Responses:

  • Agitation or restlessness during attacks (80% of patients) 1
  • Aggressive behavior (26% of patients) 1

Pain Distribution

While predominantly in the orbital-temporal region (77%), pain can also be reported in:

• Retro-orbital area (61%)
• Frontal region (55%)
• Occipital region (42%)
• Other areas: vertex, jaw, teeth, neck, shoulder 1

Diagnostic Criteria Considerations

The hallmark feature that distinguishes paroxysmal hemicrania from other primary headache disorders is its absolute response to indomethacin 1, 2. This response is so characteristic that it is considered a diagnostic criterion.

However, clinical presentation may vary:

• Some patients may lack cranial autonomic features 2
• Some may have fewer than 5 attacks per day 2
• Some may have incomplete response to indomethacin 2
• Some may be unable to tolerate indomethacin due to side effects 3, 4

Diagnostic Challenges

Overlap with Other Headache Disorders

There may be overlap between paroxysmal hemicrania and cluster headache, with some patients showing features of both conditions 3. The key differences include:

Feature	Paroxysmal Hemicrania	Cluster Headache
Duration	2-30 minutes	15-180 minutes
Frequency	>5 attacks daily	1-8 attacks daily
Gender	Female predominance	Male predominance
Indomethacin response	Absolute	Variable/Poor

Secondary Causes

Always consider secondary causes of paroxysmal hemicrania-like symptoms, especially with:

• Atypical clinical features
• Poor response to indomethacin
• Abnormal neurological examination
• Onset after age 50

Management Approach

1. First-line treatment: Indomethacin (100-200 mg daily) 1
2. For indomethacin-intolerant patients: Consider topiramate as an alternative 4

Clinical Pearls

• The indomethacin test (oral or intramuscular) is recommended for diagnosis in patients with suspected paroxysmal hemicrania 1
• Gastrointestinal protection should be considered for patients on long-term indomethacin therapy
• Unlike migraine, paroxysmal hemicrania attacks are much shorter and more frequent
• Unlike cluster headache, paroxysmal hemicrania shows an absolute response to indomethacin
• Some patients may require long-term prophylactic treatment as the condition can be chronic

When evaluating a patient with suspected paroxysmal hemicrania, focus on attack duration, frequency, autonomic features, and response to indomethacin as the key diagnostic elements.