Although TEWL scores are well known to be increased and reflective of barrier defects in atopic dermatitis,27 barrier dysfunction as reflected in TEWL measures has also been shown to be present in psoriatic lesions21 and can be normalized in psoriasis patients after effective UVB phototherapy28 and moisturizers application.29 We found TEWL scores reached a peak on day 5 in WT mice with a 46% reduction in TRPA1 KO mice, raising the prospect that TRPA1 may contribute to IMQ‐mediated barrier defects. Here, TRPA1 is linked to psoriasis.