Bilastine is a second generation antihistamine drug for the treatment of allergic rhinoconjunctivitis and urticaria (hives).it exerts its effect as a selective histamine h1 receptor antagonist, and has a effectiveness similar to cetirizine, fexofenadine and desloratadine.dosage:a therapeutic dosage of bilastine is 20 mg once a day orally and shows a rapid onset of action (within 30-60 minutes). it should be taken only by children older than 12 years and adults.