Sumatriptan aborts an acute migraine attack by acting on which receptor subtype?

• A 5-HT2A receptors on cortical neurons, inhibiting spreading depression
• B 5-HT3 receptors on brainstem nausea pathways
• C 5-HT7 receptors on cerebral arterial smooth muscle
• D 5-HT1B/1D receptors on cranial blood vessels and trigeminal nerve terminals ✓

Explanation

Sumatriptan (triptan class) agonises 5-HT1B receptors on cranial blood vessels causing vasoconstriction of dilated meningeal arteries, and 5-HT1D receptors on trigeminal nerve terminals inhibiting the release of vasodilatory neuropeptides (CGRP, substance P). These dual actions abort neurogenic inflammation. 5-HT2A antagonism is the mechanism of methysergide (migraine prophylaxis); 5-HT3 antagonists are antiemetics.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.