Once-daily cetirizine effective in the treatment of seasonal allergic rhinitis in children aged 6 to 11 years: a randomized, double-blind, placebo-controlled study.

Cetirizine (once daily), a highly selective H1-antagonist, is efficacious for treating seasonal allergic rhinitis (SAR), perennial allergic rhinitis, and chronic idiopathic urticaria. A 4-week, randomized, double-blind, placebo-controlled trial investigated the safety and efficacy of cetirizine syrup (5 or 10 mg daily) in 209 children ages 6 to 11 years with SAR. Parents assisted patients in recording symptom severity (sneezing, nasal discharge, itchy eyes, itchy nose or mouth, conjunctivitis, nasal congestion) daily. A total symptom severity (TSS) score was derived from all symptoms, excluding nasal congestion. At baseline, TSS was comparable for all groups (range 6.8-7.0). Cetirizine 10 mg produced a significantly greater mean TSS reduction (3.2) than placebo (P < 0.05) over the treatment period. Cetirizine 5 mg once daily produced mean reductions in weekly symptom scores of 2.4; this did not differ statistically from placebo. Furthermore, cetirizine 10 mg significantly improved symptoms of itchy eyes, nose, or mouth. The most commonly reported adverse reactions to both cetirizine and placebo were headache, pharyngitis, and abdominal pain, which did not occur with an incidence statistically different from that of placebo. Once-daily cetirizine is safe for treating SAR in children ages 6-11 years. Once-daily cetirizine 10 mg provides effective improvement in symptoms and is well tolerated.