“…In contrast, high-quality trials of second-generation H 1 -antihistamines, such as cetirizine, desloratadine, fexofenadine, levocetirizine, loratadine, bilastine, and rupatadine confirm that they decrease symptoms and improve quality of life (see Table E2). 42,48,[65][66][67][68][69] Although many patients respond to standard doses of these medications, more respond to increasing the daily dose up to 4-fold; for example, in one double-blind randomized controlled trial, 13 of 40 patients became symptom free on 5 mg of levocetirizine and 28 of the 40 patients became symptom free on 10 or 20 mg of levocetirizine without experiencing adverse effects at the higher doses. Additionally, in objective tests, such as in patients with acquired cold urticaria, high-dose desloratadine (20 mg) or rupatadine (20 mg) decrease wheal volume and improve cold provocation thresholds significantly compared with standard doses.…”