Sumatriptan is used to ease the symptoms of migraine or cluster headaches. It works by releasing a natural chemical called serotonin, which causes the blood vessels around your brain to contract (narrow). This reverses the dilating (widening) of blood vessels that's believed to be part of the headache process.
Sumatriptan only works when a migraine attack has already begun. It will not prevent a migraine. Do not take it before your headache begins, or during the aura phase, as it may be less effective. Read more about migraine headaches.
Sumatriptan belongs to a group of medicines called triptans. In New Zealand, sumatriptan is available as tablets (50 mg and 100 mg) and an injection. The information on this page is about sumatriptan tablets. The injection may be better if you are vomiting, or if you develop a sudden migraine. Read more about sumatriptan injection.