Correct Answer: A. Sumatriptan
The clinical presentation—unilateral headache with nausea, photophobia, and phonophobia—is pathognomonic for migraine. Sumatriptan is a 5-HT1B/1D receptor agonist (triptan) that is the gold-standard acute abortive agent for migraine attacks in India and globally. The mechanism is twofold: (1) vasoconstriction of cranial blood vessels via 5-HT1B receptors, and (2) inhibition of trigeminal neuropeptide release via 5-HT1D receptors in the brainstem, thereby interrupting the pain cascade. Triptans are most effective when given early in the migraine attack, ideally during the prodrome or within 2 hours of onset. Sumatriptan is available in multiple formulations in India (oral 50–100 mg, subcutaneous 6 mg, nasal spray 20 mg), making it accessible across settings. It rapidly aborts the headache and associated symptoms in 60–70% of patients within 2 hours. The drug is contraindicated only in uncontrolled hypertension, coronary artery disease, and basilar/hemiplegic migraine. For acute migraine management, triptans are superior to NSAIDs and ergot derivatives because of faster onset and better tolerability. Per Indian neurology guidelines and Harrison's classification, sumatriptan is the first-line acute agent for moderate-to-severe migraine.
Why the other options are wrong
B. Propranolol — Propranolol is a prophylactic (preventive) agent, not an acute abortive drug. It is used for migraine prevention in patients with frequent attacks (≥4 per month) and works by reducing neuronal excitability and stabilizing serotonin levels. It has no role in aborting an acute migraine attack already in progress. NBE traps students who confuse prophylaxis with acute management. C. Topiramate — Topiramate is an anticonvulsant used for migraine prophylaxis, not acute treatment. It reduces migraine frequency by stabilizing neuronal membranes and enhancing GABA activity. Like propranolol, it is prescribed for chronic migraine prevention in patients with ≥4 attacks per month, not for aborting individual attacks. It has a slow onset (weeks) and is unsuitable for acute management. D. Flunarizine — Flunarizine is a calcium channel blocker used for migraine prophylaxis, particularly in India where it is widely prescribed for chronic migraine prevention. It reduces attack frequency and severity but does not abort acute attacks. Its slow onset (2–4 weeks) and lack of rapid pain relief make it inappropriate for acute migraine management. This is a common Indian trap because flunarizine is heavily marketed here.
High-Yield Facts
- Sumatriptan is a 5-HT1B/1D receptor agonist (triptan) — the gold-standard acute abortive agent for migraine.
- Migraine triad: unilateral headache + nausea/vomiting + photophobia/phonophobia — triggers triptan use.
- Triptans work best when given early (within 2 hours of onset); efficacy drops significantly if delayed.
- Prophylactic agents (propranolol, topiramate, flunarizine, amitriptyline) are for ≥4 attacks/month, NOT acute attacks.
- Contraindications to triptans: uncontrolled hypertension, coronary artery disease, basilar/hemiplegic migraine, pregnancy.
- Sumatriptan formulations in India: oral 50–100 mg, subcutaneous 6 mg, nasal spray 20 mg — choose based on severity and vomiting.
Mnemonics
ABORTIVE vs PROPHYLACTIC Acute = Abortive (Sumatriptan, NSAIDs, ergots) | Prevention = Prophylactic (Propranolol, Topiramate, Flunarizine, Amitriptyline). Use when you see 'acute attack' → think abortive; 'frequent attacks' → think prophylactic. TRIPTAN TIMING Triptans work Too late if delayed. Give within 2 hours of onset for best effect. After 4 hours, efficacy drops sharply — this is why early recognition matters in Indian emergency departments.
NBE Trap
NBE pairs migraine with propranolol and flunarizine to trap students who memorize drug names without distinguishing acute abortive therapy from chronic prophylaxis. The question's emphasis on "acute management" is the discriminator that rules out all three prophylactic agents.
Clinical Pearl
In Indian outpatient neurology, sumatriptan is often the first drug dispensed to migraine patients because it provides rapid relief and improves quality of life. However, overuse (>10 days/month) leads to medication-overuse headache (MOH), a common iatrogenic problem in India — prophylaxis should be started early in frequent migraine sufferers to prevent this cycle.
_Reference: Harrison Ch. 434 (Headache); Robbins Ch. 28 (Nervous System pathology); KD Tripathi Ch. 9 (CNS Pharmacology)_