Levocetirizine: Review of its Use in the Treatment of Seasonal Allergic Rhinitis

Background: Levocetirizine (LCZ), the active R-enantiomer of cetirizine, is a second-generation antihistamine approved for symptom treatment due to seasonal allergic rhinitis (SAR), perennial allergic rhinitis, and chronic idiopathic urticaria in patients $6 months of age. Objective: To review available literature about pharmacokinetics, pharmacodynamics, efficacy, tolerability, quality of life, and pharmacoeconomics of LCZ use in adults and children with SAR. Methods: Databases searched were: MEDLINE, CINAHL Plus with Full Text, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Cochrane Methodology Register, EMBASE, NHS Economic Evaluation Database, and Database of Abstracts of Reviews of Effectiveness. Search terms included levocetirizine, histamine H1 antagonists—non-sedating, seasonal allergic rhinitis, pregnancy, quality of life, case reports, cost, and pharmacoeconomics. Relevant article reference lists were also used to obtain additional articles. Results: LCZ exhibits rapid and extensive absorption, high affinity/selectivity for H1 receptor, and rapid onset and long duration of action. Eight articles assessing clinical efficacy were reviewed. In 4 placebo-controlled studies, LCZ 5 mg/day significantly reduced nasal symptoms in 3 studies and had similar efficacy in 1 study. LCZ was more effective in reducing SAR symptoms vs. desloratadine 5 mg/day but not vs. rupatadine (RUP) 10 mg/day, and RUP was more effective than LCZ in reducing nasal symptoms (P = 0.02). Addition of LCZ 5 mg/day to fluticasone nasal spray therapy improved nasal blockage symptoms only (P , 0.005). Studies investigating anti-inflammatory effects produced inconsistent results. LCZ was not associated with serious adverse events and is generally well tolerated with complaints of somnolence and fatigue; also, there was an increase in febrile seizures in infants. Conclusion: LCZ is an effective and well-tolerated second-generation antihistamine used for the treatment of SAR in adults and children, but its effects on inflammatory markers and performance versus other treatment options require further investigation.