These signaling pathways interact with mediators, such as amines (histamine, serotonin/5-HT, IL-6), peptides (bradykinin, SP, CGRP, neurotrophin) and phospholipid metabolites (cannabinoids, eicosanoids, platelet-activating factor), and result in the occurrence and development of pruritus and erythema (Song et al., 2018). This evidence concerns the gene CALCA and Erythema.