C1. Overview: This will be a randomized, double-blind, placebo-controlled clinical research trial testing the efficacy of intravenous dexamethasone sodium phosphate as adjuvant therapy for acute migraine headaches. All subjects will receive standard-of-care migraine-abortive medication for their migraines. In addition, they will receive either ten milligrams of intravenous dexamethasone sodium phosphate or a comparable amount of placebo. Subjects will be followed by telephone 24 hours after medication administration.