Imitrex (generic: sumatriptan) 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 in tablet, nasal spray, and injectable forms and is taken at the first sign of a migraine headache.

Common side effects of Imitrex include tingling or numbness in fingers or toes, weakness, and tiredness. Imitrex can cause drowsiness. Do not drive a car or operate machinery if you have these symptoms.