What is the treatment for paroxysmal hemicrania?

Treatment for Paroxysmal Hemicrania

Indomethacin is the first-line and definitive treatment for paroxysmal hemicrania, with an exquisite responsiveness that is considered pathognomonic for this condition. 1, 2

Clinical Characteristics of Paroxysmal Hemicrania

Paroxysmal hemicrania (PH) is a rare primary headache disorder belonging to the trigeminal autonomic cephalalgias (TACs) characterized by:

• Severe, unilateral headaches primarily in the ophthalmic trigeminal distribution (V1), though pain can also be reported in other areas including orbital, temporal, retro-orbital, and frontal regions 3
• Short-lasting attacks with a mean duration of approximately 17 minutes 3
• High frequency of attacks (mean of 11 per day) 3
• Prominent ipsilateral cranial autonomic features including:
  • Lacrimation (87% of patients) 3
  • Conjunctival injection (68%) 3
  • Rhinorrhea (58%) 3
  • Nasal congestion (54%) 3
  • Ptosis and facial flushing (54%) 3

Treatment Algorithm

First-Line Treatment

• Indomethacin is the treatment of choice and considered diagnostic when effective 1, 2
  • Initial dosing: Start with 25 mg three times daily and titrate up as needed 2
  • Maintenance dosing: Typically 75-150 mg daily in divided doses 2
  • Diagnostic test: Indometacin test (100-200 mg intramuscularly) can be used to confirm diagnosis 3

Alternative Options for Patients Unable to Tolerate Indomethacin

For patients who develop gastrointestinal side effects or have contraindications to indomethacin:

• Celecoxib has shown good results for both acute and prolonged treatment 1
• Piroxicam is effective for acute treatment 1
• Topiramate and gabapentin are reasonable alternatives for prolonged treatment 1

Treatment Duration and Monitoring

• Patients typically need to be maintained on indomethacin for several months before trials of dose reduction can be attempted 2
• Monitor for gastrointestinal side effects, which are the most common adverse events requiring discontinuation 4
• The disorder has a tendency toward chronicity, so long-term treatment may be necessary 2

Clinical Pearls and Pitfalls

• Diagnostic pitfall: PH is often misdiagnosed as sinusitis due to the prominent autonomic features 4
• Treatment pitfall: Failure to recognize PH leads to unsuccessful trials of drugs effective in other primary headaches 2
• Clinical pearl: Response to indomethacin is considered the sine qua non for diagnosis of PH 3
• Clinical pearl: Some patients may have overlapping features with cluster headache, which can complicate diagnosis 4

Pathophysiology

• Hypothalamic and trigeminovascular mechanisms are implicated in PH 2
• Neuroimaging findings demonstrate posterior hypothalamic activation similar to other TACs 2

Early recognition of paroxysmal hemicrania is crucial for prompt initiation of effective treatment with indomethacin, which can provide complete or near-complete resolution of headache and autonomic symptoms 5.