Chronic idiopathic urticaria (CIU) is a common and frustrating disorder defined as a regular recurrence of hives for a period of more than 6 weeks, and has a major impact on patients' daily quality of life--H1 receptor antagonists are considered to be particularly effective in reducing pruritus, and are recommended as first-line treatment in patients with CIU. However, the efficacy of the treatment is insufficient.To evaluate the efficacy of desloratadine in CIU in Israeli patients.An open label multicenter study in 10 centers in Israel. Upon completion of 3-14 days screening for eligibility, eligible patients were given desloratadine 5 mg for 4 weeks. The DLQI questionnaire and the severity of CIU were assessed at baseline and each week for 28 days.One hundred and four patients aged 19 to 85 years (mean +/- SD 45.6 +/- 15.6) who suffered from moderate CIU, despite previous treatment with anti-histamine agents, were selected and treated with desloratadine 5 mg daily for 28 days. There was significant improvement for dermatologic quality of life in each of 10 parameters and in work productivity, and significant decrease in CIU symptoms and signs including the number and size of hives. In the overall evaluation of treatment 51% of patients reported complete or marked relief and 20% had no relief. Adverse events were reported as mild in 10 patients and moderate to severe in 2 patients who discontinued the study due to headache.Desloratadine can be successfully used in the treatment of CIU.