Ischemic Stroke Associated With Calcitonin Gene-Related Peptide Inhibitor Therapy for Migraine: A Case Report.

Calcitonin gene-related peptide (CGRP) is involved in nociception and neurogenic inflammation in migraine, but also serves as a potent vasodilator acting on intracranial arteries. This latter effect raises concern about the possibility of drugs inhibiting CGRP precipitating cerebral ischemia. We describe a 41-year-old woman with migraine without aura who developed a right thalamic infarction following a first dose of erenumab, a CGRP-receptor blocker. Stroke onset occurred during a typical migraine. Imaging demonsrated right posterior cerebral artery near-occlusion initially with normalization of the vessel at follow-up imaging 2 months later, suggesting vasospasm as a possible mechanism. Extensive evaluation revealed no other specific cause of stroke or vascular risk factors aside from long-term use of oral contraceptive pills. CGRP inhibitors might be associated with ischemic stroke due to blockade of normal cerebral vasodilatory regulatory function.