TRPV1 and psoriasis: A positive correlation between pruritus intensity and stress was reported by Amatya et al. (r = 0.8, p < 0.05) and Reich et al. (p = 0.015).16,21 Heat or warm stimuli can provoke itch via transient receptor potential vanilloid subtype 1 (TRPV1) and calcitonin gene-related peptide (CGRP), both of which are involved in the pathogenesis of itching with psoriasis.7,38 In summary, studies in countries with subtropical climates, such as Thailand and Singapore, report hot temperatures and sweating as itch aggravators and cold water and cold temperatures as itch relievers.