<p>This preparation contains Levocetirizine Dihydrochloride. Levocetirizine is the active (Levo) isomer of cetirizine. It is a new highly effective and well-tolerated nonsedating antihistamine with potent antiallergic properties. It has a two-fold higher affinity for H1 receptors than cetirizine. Levocetirizine has a rapid and long-acting action, allowing once-a-day administration.</p>