Epidemiology

Etiology

Pathophysiology

• Activation of meningeal nociceptors
  • Dilatation of intracranial blood vessels → activation of meningeal nociceptors
  • Activation of the trigeminovascular pathway: activation of trigeminal neurons → release of vasoactive neuropeptides such as substance P
• Dysregulation of pain sensitization in the trigeminal system (CN V): cortical spreading depression → dysregulation of trigeminovascular neurons → neurogenic inflammation → hypersensitization → nausea, loss of appetite, yawning, fatigue, anxiety, depression
• Activation of the autonomic nervous system: external physiological and emotional stimulation (e.g., hormonal changes, stress) → hypothalamic response to the change in homeostasis → hypothalamic neurons influence the autonomic nervous system → shift toward a parasympathetic tone → constriction and dilatation of intracranial, especially the meningeal, blood vessels

Clinical features

Diagnostics

Treatment

Abortive therapy for migraines

• Treat nausea and vomiting, if present.
  • Accompanying vomiting makes absorption of oral medications (e.g., oral NSAIDs) unreliable.
  • IV fluids
  • Parenteral antiemetics: e.g., metoclopramide, prochlorperazine

Mild to moderate headache

• First-line treatment consists of NSAIDs, acetaminophen, acetylsalicylic acid, or combinations including caffeine.

Moderate to severe headache

• Parenteral antidopaminergics
  • Metoclopramide
  • Prochlorperazine PLUS diphenhydramine
• Migraine-specific agents: triptans (e.g., sumatriptan) OR ergotamine; do not combine these agents!
  • Triptans
    • Sumatriptan
    • 5-HT1B/1D receptor agonists that cause:
      • Vasoconstriction of (dilated) cranial and basilar arteries
      • Inhibition of trigeminal nerve nociception
      • Inhibition of vasoactive peptide secretion
    • Adverse effects
      • Vasospasm of coronary vessels → coronary ischemia (rare)
      • Paresthesia and sensation of cold in the extremities
      • Serotonin syndrome (if taken with other 5-HT agonists)

Prophylactic therapy of migraine

• Lifestyle modifications
  • Exercise in moderation
  • Maintain a healthy diet
  • Identify and try to avoid potential triggers
  • Follow a regular sleeping schedule
• General prophylaxis
  • First-line
    • Anticonvulsants (e.g., topiramate, divalproex)
    • Beta blockers (e.g., propranolol, metoprolol (off-label), timolol)
  • Second-line
    • Tricyclic antidepressant: amitriptyline
    • NSAIDs