Reversible cerebral vasoconstriction syndrome developing after an erenumab injection for migraine prevention.

A case of reversible cerebral vasoconstriction syndrome developing after treatment with a calcitonin gene-related peptide monoclonal antibody is presented. The timing of the new type of headache occurring 2 days post erenumab injection suggests a possible cause and effect relationship. Reversible cerebral vasoconstriction syndrome as a possible treatment-related complication to the usage of calcitonin gene-related peptide monoclonal antibodies needs to be studied further.