Serum levels of HIF‐1α, GDF‐15, FGF‐21, CGRP, and PACAP‐38 were significantly higher in migraine patients. The serum levels of these peptides were also higher in patients with CM than in EM, and higher in the ictal period than in the interictal period. The gene discussed is CALCA; the disease is erythema multiforme.