Sumatriptan
💡 If a patient does not respond to one 5HT1-receptor agonist, an alternative 5HT1-receptor agonist should be tried.
Always check the BNF here.
🔬 Mode of Action
- 5HT1-receptor agonists (triptans) cause selective vasoconstriction of cranial blood vessels and inhibit trigeminal nerve activation, relieving migraine headache and associated symptoms.
💊 Indications & Doses
- Acute migraine and cluster headache:
- Oral: Sumatriptan 50–100 mg; may repeat after ≥2 hrs if headache recurs; max 300 mg/24h.
- Subcutaneous (SC): Sumatriptan 6 mg stat; may repeat after ≥1 hr; max 12 mg/24h.
- Intranasal: 11–20 mg; max 40 mg/24h.
- ⚠️ Not indicated for hemiplegic, basilar, or ophthalmoplegic migraine.
⚖️ Interactions
- See BNF for full list (notably with SSRIs, MAOIs, and other triptans).
⚠️ Cautions
- Refer to BNF for details, but use carefully in patients with cardiovascular risk factors or poorly controlled hypertension.
🚫 Contraindications
- Ischaemic heart disease or previous MI.
- Coronary vasospasm (e.g. Prinzmetal’s angina).
- Uncontrolled or severe hypertension.
🤕 Side Effects
- Tingling, flushing, sensations of heat or heaviness.
- Chest or throat pressure (non-cardiac but alarming to patients).
- Dizziness, fatigue, nausea, vomiting.
- Rare: anaphylaxis.
💡 Teaching Pearls
- 🧠 Triptans should be taken at headache onset, not during aura phase (ineffective if taken too early).
- 🚑 Always exclude cardiovascular contraindications before prescribing - triptans can provoke coronary vasospasm.
- ⏱️ Rapid SC onset (<15 min) makes it useful in cluster headache, where speed of relief is crucial.
- 🔄 Non-response to one triptan doesn’t rule out benefit from another; switching is reasonable.
📚 References
