Familial hemiplegic migraine (FHM) is a rare autosomal dominant neurological disorder linked to mutations in several genes, including CACNA1A, ATP1A2, SCN1A, and PRRT2. It is characterized by reversible motor weakness that often leads to its misdiagnosis as a stroke or transient ischemic attack (TIA). Here, CACNA1A is linked to familial hemiplegic migraine.