methysergide

[ meth-uh-sur-jahyd ]
/ ˌmɛθ əˈsɜr dʒaɪd /

noun Pharmacology.

an ergot alkaloid derivative, C21H27N3O2, used in the prophylaxis and treatment of migraine and cluster headaches.

Origin of methysergide

1960–65; meth- + (l)yserg(ic) (see lysergic acid) + -ide