A patient receives sumatriptan for an acute migraine. Its mechanism of action involves:
- A Non-selective 5-HT receptor antagonism, reducing neurogenic inflammation in the trigeminal vascular system
- B Selective 5-HT1B/1D receptor agonism causing intracranial vasoconstriction and inhibition of trigeminal perivascular neuropeptide (CGRP) release ✓
- C Selective 5-HT2B receptor agonism stimulating nitric oxide release in meningeal vessels
- D CGRP receptor antagonism preventing vasodilator peptide binding at meningeal vessels
Correct answer: B. Selective 5-HT1B/1D receptor agonism causing intracranial vasoconstriction and inhibition of trigeminal perivascular neuropeptide (CGRP) release
Explanation
Sumatriptan and other triptans are selective 5-HT1B/1D agonists. 5-HT1B receptor activation on intracranial blood vessels causes vasoconstriction, counteracting the pathological vasodilation of migraine. 5-HT1D receptor activation on trigeminal nerve endings inhibits release of vasoactive neuropeptides (CGRP, substance P), blocking neurogenic inflammation. CGRP antagonists (gepants) are a separate class.
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.