What are the parameters for managing a hemiplegic migraine?

Management Parameters for Hemiplegic Migraine

Hemiplegic migraine requires specialized management that differs from standard migraine treatment, with careful consideration of medication contraindications and a focus on both acute and preventive therapies to reduce attack frequency and severity.

Diagnosis Parameters

Clinical Criteria for Hemiplegic Migraine

• Must meet ICHD-3 criteria for migraine with aura, plus:
  • At least two attacks fulfilling criteria
  • Motor weakness (hemiplegia) as an aura symptom
  • At least one additional fully reversible aura symptom:
    • Visual
    • Sensory
    • Speech/language
    • Brainstem symptoms
    • Retinal symptoms 1

Key Diagnostic Features

• Motor weakness is typically unilateral
• Aura symptoms spread gradually over ≥5 minutes
• Each aura symptom lasts 5-60 minutes (motor symptoms may last <72 hours)
• Aura is accompanied by or followed by headache within 60 minutes 1, 2

Classification

• Familial Hemiplegic Migraine (FHM): At least one first-degree relative has identical attacks
• Sporadic Hemiplegic Migraine (SHM): No family history of identical attacks 3

Differential Diagnosis Evaluation

• Neuroimaging (MRI preferred) to rule out:
  • Stroke/TIA
  • Arterial dissection
  • CADASIL
  • MELAS
  • Moyamoya disease 1
• Consider EEG and CSF analysis to exclude other causes of focal neurological symptoms
• Genetic testing for CACNA1A, ATP1A2, and SCN1A mutations (particularly with additional symptoms like chronic ataxia or epilepsy) 3, 2

CAUTION: Conventional cerebral angiography is contraindicated in hemiplegic migraine as it may trigger attacks 3

Acute Treatment Parameters

First-Line Options

• Acetaminophen and NSAIDs (e.g., aspirin, ibuprofen, naproxen sodium) 1, 3
• Antiemetics for accompanying nausea/vomiting:
  • Metoclopramide (10mg oral/IV)
  • Prochlorperazine (25mg oral/suppository) 1

Second-Line Options

• Non-oral routes when nausea/vomiting is prominent:
  • Intranasal or injectable formulations
  • Antiemetics as adjunctive therapy 1

IMPORTANT CONTRAINDICATION: Triptans and ergotamine derivatives are generally contraindicated in hemiplegic migraine due to theoretical risk of vasoconstriction 1, 4

Rescue Therapy

• For severe, prolonged attacks:
  • Consider hospitalization for severe, prolonged aura 2
  • Intravenous hydration
  • Carefully monitored opioids may be considered when other treatments fail and when risk of abuse has been addressed 1

Preventive Treatment Parameters

Indications for Preventive Therapy

• Two or more hemiplegic migraine attacks per month
• Attacks producing disability for three or more days per month
• Use of rescue medication more than twice a week
• Failure of acute treatments or contraindications for such treatments 1

First-Line Preventive Options

1. Calcium channel blockers:

   • Verapamil (evidence of efficacy in case reports) 3, 5
   • Flunarizine (where available) 3

2. Anticonvulsants:

   • Sodium valproate
   • Lamotrigine (particularly effective for aura symptoms)
   • Acetazolamide (especially in familial cases) 3

Alternative Preventive Options

• Topiramate
• Candesartan
• Pizotifen 3

Emerging Therapies

• Anti-CGRP monoclonal antibodies (galcanezumab) have shown promise in reducing both headache severity and days with weakness in some hemiplegic migraine patients 6

Medications to Use with Caution

• Beta-blockers (e.g., propranolol) - controversial in hemiplegic migraine due to theoretical risk of worsening intracranial vasoconstriction, though evidence of adverse effects is insufficient to absolutely contraindicate 1, 3

Special Considerations

Hormonal Factors

• Oral contraceptives may exacerbate migraine and alter coagulation
• Consider alternative birth control methods for women with hemiplegic migraine 1

Genetic Implications

• Three genes identified (CACNA1A, ATP1A2, SCN1A) affecting ion channels
• Patients with familial hemiplegic migraine mutations may develop persistent neurological deficits and potentially higher stroke risk 1, 3

Monitoring Parameters

• Track attack frequency, severity, duration
• Monitor degree of disability from attacks
• Assess response to treatments
• Document adverse effects from medications
• Identify and track potential triggers 1

Key Pitfall: Failure to distinguish hemiplegic migraine from stroke can lead to inappropriate treatment. Always complete thorough evaluation to rule out other causes of focal neurological deficits before confirming diagnosis.