A number of limitations can be mentioned for this study; first, as the peripheral levels of TRPV1, VIP, and PACAP were assessed merely in the interictal phase of migraine in EM patients, to achieve more comprehensive results, it is necessary to measure the CSF and serum levels of these biomarkers both between and during attacks in EM patients. This evidence concerns the gene ADCYAP1 and erythema multiforme.