Sumatriptan

What it is

Sumatriptan is a triptan, a selective agonist at serotonin 5-HT1B/1D receptors. It constricts dilated cranial blood vessels and dampens the release of inflammatory neuropeptides from trigeminal nerve endings, which is how it stops a migraine attack that has already started. It is used for migraine, as an attack treatment rather than a preventive one.

A usual adult range, not a national label — the dose and the timing differ by country and by product.

Used for

• Migraine

Approved uses differ by country — some of these may be off-label or unapproved where you live.

What to know while taking it

Food makes no difference to whether it works, so it can be taken with or without a meal, but it is meant for attacks only and the treatment days in a month are limited: in the UK the MHRA-approved label caps only the amount taken in a day, while the monthly limit comes from NICE guidance. Frequent use tends to turn into medication-overuse headache. Because it acts on serotonin receptors, combining it with SSRI and SNRI antidepressants such as sertraline, escitalopram, fluoxetine or venlafaxine carries a risk of serotonin excess, so the full medication list belongs with the prescriber. It can also raise blood pressure briefly, and it is not used in uncontrolled hypertension or coronary or cerebrovascular disease; it may cause brief tightness or heaviness in the chest, neck or jaw.

When to see a doctor

Chest tightness or pain, especially if it is severe or lasts, needs medical attention rather than another dose. Agitation, shivering, fever, muscle twitching or a racing heart while also on an antidepressant, or attacks frequent enough that the monthly limit is being reached, are reasons to see a doctor.

Worth knowing

• Frequent use brings on medication-overuse headache — agree a monthly limit with a doctor
• Chest tightness needs medical attention
• Can raise blood pressure