Sumatriptan

Sumatriptan is a selective serotonin (5-HT1B/1D) receptor agonist, commonly referred to as a triptan, developed specifically for the acute treatment of migraine attacks.

It acts on intracranial blood vessels to cause vasoconstriction of dilated cranial arteries, inhibits the release of vasoactive neuropeptides from trigeminal nerve endings, and blocks pain signal transmission in the trigeminal nucleus caudalis.

Sumatriptan was the first triptan to market and remains the most widely prescribed acute migraine treatment worldwide.

Clinical trials demonstrate significant relief of headache, nausea, photophobia, and phonophobia within 2 hours in approximately 50-60% of patients at the 100 mg dose.

It is effective against migraine with and without aura. The BNF lists sumatriptan as first-line acute treatment for moderate-to-severe migraine when simple analgesics are insufficient.

NICE Clinical Knowledge Summary supports triptan use as early as possible in the migraine attack for maximum benefit. Sumatriptan is also licensed for cluster headache (subcutaneous injection).

It does not prevent migraine attacks and is not effective for tension-type headache.

Take one 50 mg or 100 mg tablet as early as possible after the onset of migraine headache. Swallow whole with water.

If the headache responds to the first dose but recurs, a second dose may be taken after a minimum interval of 2 hours. Do not take more than 300 mg in any 24-hour period.

If the first dose has no effect at all, do not take a second dose for the same attack — a different treatment approach should be discussed with your prescriber.

Sumatriptan is not effective if taken during the aura phase before headache onset. Avoid use within 24 hours of any other triptan or ergotamine.

Can be taken with or without food, though absorption may be delayed during migraine due to gastric stasis.

The recommended starting dose is 50 mg; this may be increased to 100 mg if 50 mg provides insufficient relief. Some patients respond to 25 mg. Maximum dose in 24 hours: 300 mg (oral).

For patients with mild hepatic impairment, the maximum single dose is 50 mg. Sumatriptan is not recommended in severe hepatic impairment. No dose adjustment is required for renal impairment.

In patients taking MAO-A inhibitors (e.g. moclobemide), the maximum dose is 50 mg and concurrent use requires caution.

Co-administration with potent CYP3A4 inhibitors does not significantly affect sumatriptan pharmacokinetics as it is primarily metabolised by MAO-A.

Side effects per SmPC frequency data.

Common (≥1/100 to <1/10): Tingling, paraesthesia, sensation of heaviness, warm or hot sensations, flushing, dizziness, drowsiness, transient blood pressure elevation, dyspnoea, nausea, vomiting (may also be migraine-related), muscle pain, fatigue.

Uncommon (≥1/1,000 to <1/100): Bradycardia, tachycardia, palpitations, hypotension, Raynaud's phenomenon, visual disturbances.

Rare (≥1/10,000 to <1/1,000): Coronary artery vasospasm, myocardial infarction (isolated reports in patients with cardiovascular risk factors), seizures, anaphylaxis, serotonin syndrome (especially with concurrent serotonergic drugs).

Chest symptoms: Tightness, heaviness, or pressure in the chest and throat occurs in approximately 3-5% of patients.

This is usually non-cardiac and attributed to skeletal muscle or oesophageal spasm, but cardiac causes should be excluded in at-risk individuals.

Sumatriptan must not be given to patients with uncontrolled hypertension or established ischaemic heart disease, cerebrovascular disease, peripheral vascular disease, or Wolff-Parkinson-White syndrome.

A cardiovascular assessment is recommended before prescribing to patients with multiple cardiovascular risk factors (e.g.

smoking, hypertension, hyperlipidaemia, diabetes, strong family history, men >40, postmenopausal women). The first dose may be given under medical supervision in such cases.

Medication overuse headache (MOH) can develop if triptans are used on more than 10 days per month; this requires prescriber review and managed withdrawal.

Do not co-administer with ergotamine (24-hour washout) or other triptans.

Serotonin syndrome risk exists with concurrent SSRIs, SNRIs, or MAOIs — monitor for symptoms (agitation, myoclonus, hyperthermia, hyperreflexia).

Sumatriptan is contraindicated in patients with hypersensitivity to sumatriptan or any excipient, ischaemic heart disease (including angina, prior MI, documented silent ischaemia), coronary vasospasm (Prinzmetal's angina), cerebrovascular disease (stroke or TIA), peripheral vascular disease, moderate-to-severe hypertension or uncontrolled mild hypertension, severe hepatic impairment, concurrent use of ergotamine or other triptans (within 24 hours), and concurrent or recent use of MAOIs (within 2 weeks of irreversible MAOIs or 24 hours of reversible MAO-A inhibitors).