Isometheptene (usually as isometheptene mucate) is a sympathomimetic amine sometimes used in the treatment of migraines and tension headaches due to its vasoconstricting properties; that is, it causes constriction (narrowing) of blood vessels (arteries and veins).

Isometheptene's vasoconstricting properties arise through activation of the sympathetic nervous system via epinephrine and norepinephrine. These compounds elicit smooth muscle activation leading to vasoconstriction by interacting with cell surface adrenergic receptors.