Hemiplegic migraine (HM) is a rare variety of migraine with aura characterized by the presence of a motor weakness during the aura. Hemiplegic migraine has two main forms depending on the familial history: patients with at least one first- or second-degree relative who has aura including motor weakness have familial hemiplegic migraine (FHM); patients without such familial history have sporadic hemiplegic migraine (SHM). The disease is Monarch Disease Ontology entry MONDO_0018925 (familial or sporadic hemiplegic migraine). Also known as: Hemiplegic Migraine, hemiplegic migraine.