A number of second-generation non-sedating antihistamines are used in clinical practices over the world. However, long-term safety and efficacy have not been proved high level evidence based medicine. We have performed an open-label, multicenter, phase III study to evaluate the long-term safety and efficacy of bilastine, a novel non-sedating H-1-antihistamine for patients with chronic spontaneous urticaria (CSU) or pruritus associated with skin diseases (trial registration no. JapicCTI-142528). Patients aged 18-74 years were treated with bilastine 20 mg once daily for up to 52 weeks. Safety and tolerability were assessed on the basis of adverse events (AE), bilastine-related AE, laboratory tests and vital signs. Efficacy was assessed based on rash score, itch score, overall improvement and quality of life. One hundred and ninety-eight patients enrolled, 122 of whom (61.6%) completed the 52-week treatment period. AE were reported in 64.5% and bilastine-related AE in 2.5% of patients throughout the 52-week treatment period. All AE were mild to moderate in severity. AE associated with the nervous system occurred in 10 patients (5.1%) including seven patients (3.6%) with headache. Somnolence reported in two of these patients (1.0%) was related to bilastine. All efficacy variables improved during treatment with bilastine. In conclusion, long-term treatment with bilastine 20 mg once daily for 52 weeks is safe and well tolerated in Japanese patients with CSU or pruritus associated with skin diseases. Bilastine improved disease symptoms of both conditions early in treatment, and the efficacy was maintained throughout the treatment.