A study published in the Journal of Investigational Allergology and Clinical Immunology assessed whether the change in histamine-induced wheal and flare measurements 24 hours after administration of antihistamine can predict the efficacy of treatment. In this multicenter, triple-blind, randomized study, patients received a daily oral dose of cetirizine, fexofenadine, bilastine, desloratadine, or ebastine over 8 weeks. After 4 weeks, a higher dose of antihistamine was administered to those who did not experience a clinical response. It was observed that 24 hours after administration of antihistamine, inhibition of the histamine wheal up to >75% was significantly associated with better Urticaria Activity Score (UAS) and rates of disease control (DLQI) scores. In addition, safety and efficacy of the 5 antihistamines were similar. Furthermore, after updosing, rates of disease control (DLQI score <5) increased from 58.7% to 76.7%. From the results, it was inferred that measurement of the histamine-induced wheal can predict which patients will have a strong clinical response to antihistamines. However, this measure has limited utility for identifying non-responders. It was stated that the clinical significance of these findings could be relevant in developing new urticaria treatment regimens.