Comparative efficacy of non-sedating antihistamine updosing in patients with chronic urticaria

Introduction Urticaria and angioedema lasting more than 6 weeks have been designated as chronic urticaria (CU). It encompasses two major subtypes: chronic spontaneous urticaria (CSU) (previously known as chronic idiopathic urticaria) (CIU) and chronic inducible urticaria. CSU has been defined as wheals and/or angioedema that are endogenous and independent of any external physical stimulus. It affects 0.5 to 1% of the population [1]. In 40 to 45% of patients with CSU autoantibodies to the high affinity IgE receptor (FcεRI) or to IgE itself are thought to play a psathogenic role, whereas 55 to 60% of cases are considered idiopathic [2]. Inducible urticarias include all forms of physical urticarias (cold-induced, heat-induced, solar, and pressure urticaria). According to the International Guidelines for the management of urticaria and angioedema non-sedating, second generation antihistamines (NSAHs) are recommended for the treatment of CU [3]. Nevertheless, a considerable proportion of patients do not respond sufficiently to NSAHs. According to Humphreys and Hunter up to 40% of patients with CU may not achieve good control with antihistaminic therapy [4]. They reported that out of 390 CU patients who were treated with antihistamines 44% responded well, 29% became asymptomatic, and 15% showed partial improvement. In a recent paper from Japan it was observed that the improvement rates (defined as a urticaria symptom score UAS ≤ 3) in 117 CU patients who received standard doses of AHs were