Migraine is one of the most prevalent and disabling disorders worldwide.1 In addition to triptans, which are used as abortive medications for acute migraine attacks, the US Food and Drug Administration (FDA) has approved several preventive treatments for migraine, including propranolol, topiramate, and onabotulinumtoxinA. Although most of these therapies are relatively inexpensive or available as generics, patients frequently develop symptoms refractory to these agents.2