A multitude of mediators, the majority of which are released upon stress challenge, act as mast-cell activators. The activation subsequently results in the synthesis or the release of pre-stored mediators, which may then trigger a wealth of dermatological diseases. CGRP, calcitonin gene-related peptide; CRH, corticotropin-releasing hormone; cysLTs, cysteinyl leukotrienes; NGF, nerve growth factor; PACAP, pituitary adenylate cyclase-activating polypeptide; PGD2, prostaglandin D2; SCF, stem cell factor; SP, substance P; TGF-β, transforming growth factor-β; TNF, tumor necrosis factor; Ucn, urocortin; VEGF, vascular endothelial growth factor; VIP, vasoactive intestinal peptide.