Levocetirizine (as levocetirizine dihydrochloride) is a third generation non-sedative antihistamine, developed from the second generation antihistamine cetirizine. Chemically, levocetirizine is the active enantiomer of cetirizine. Levocetirizine works by blocking histamine receptors. It does not prevent the actual release of histamine from mast cells, but prevents it binding to its receptors. This in turn prevents the release of other allergy chemicals and increased blood supply to the area, and provides relief from the typical symptoms of hayfever.
It is claimed to be more effective and with fewer side effects than the second generation drugs; however, this claim is not clearly supported by the available clinical literature.
It is available as 5mg strength tablets and a 0.5mg/mL oral solution.
Comparative efficacy of fexofenadine and levocetirizine in chronic idiopathic urticaria.(Correspondence Column)
Oct 01, 2007; Byline: K. Godse, A. Jain, P. Pharande Chronic idiopathic urticaria (CIU) is defined by the almost daily presence of urticaria...
Clinical Pharmacokinetics and Pharmacodynamics of Desloratadine, Fexofenadine and Levocetirizine: A Comparative Review
Apr 01, 2008; Abstract Second-generation histamine H^sub 1^ receptor antagonists were developed to provide efficacious treatment of allergic...