Imitrex (generic: sumatriptan) injection is a prescription medication used to treat migraine headaches once they have started. Imitrex belongs to a group of drugs called serotonin receptor agonists or "triptans", which relieve pain by narrowing blood vessels around the brain.

This medication comes as a tablet, a nasal spray and in an injectable form to be injected under the skin when migraine symptoms appear. This article focuses on Imitrex Injection.

Common side effects of Imitrex include warm, hot, burning feeling to the face, weakness, and tiredness. Imitrex can cause drowsiness. Do not drive a car or operate machinery if you have these symptoms.