Updated treatment guideline of chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU), also known as chronic idiopathic urticaria, is a common chronic inflammatory skin disorder that has a prevalence of 0.5% to 1% in the general population. It affects daily normal life and work productivity, with significant impacts on quality of life. Generally, the management of CSU uses a step-wise approach. Although second-generation H1 antihistamines are an effective mainstay of CSU, approximately 20% of patients are resistant to conventional antihistamine monotherapy. Evidence-based and expert consensus-based treatment guidelines of CSU can be a useful resource for primary care physicians and specialists. This review presents diverse information to support decision-making for individualized treatment plans in this special population. Several major therapeutic advances have occurred in recent years. Omalizumab, an immunoglobulin G humanized monoclonal anti-immunoglobulin E antibody that prevents binding of immunoglobulin E to the high-affinity immunoglobulin E receptor has shown safety and efficacy in patients with intractable CSU. In well-controlled clinical trials in patients with refractory CSU who received add-on therapy with subcutaneous omalizumab (300 mg every 4 weeks for 12 or 24 weeks), the rates of complete response were significantly higher in the omalizumab group (relative risk, 4.55; P<0.0001). The introduction of omalizumab as an add-on therapy to H1 antihistamines as a management option has markedly improved the therapeutic possibilities for CSU and the quality of life of CSU patients. Nevertheless, many patients still do not tolerate or benefit from existing therapies, including omalizumab. There are ongoing studies investigating the treatment potential of novel therapeutic targets in CSU.