A 32-year-old woman with a history of migraine without aura…

A 32-yeаr-оld wоmаn with а histоry of migraine without aura presents with unilateral throbbing headache, photophobia, and nausea that began 2 hours ago. She reports similar episodes monthly. She asks for a medication to take when the headache starts, not daily. Which statement best describes the pharmacology and appropriate use of sumatriptan?