Assessment of the efficacy and safety of three dose levels of cetirizine given once daily in children with perennial allergic rhinitis.

The present study compared the efficacy and safety of three dose levels of cetirizine (2.5, 5, and 10 mg) once a day with placebo over 14 days in 6-12-year-old children with perennial allergic rhinitis. The design was a double-blind, randomized, multicenter, parallel-group study. Five symptoms (sneezing, nasal discharge, nasal obstruction, nasal pruritus, and ocular pruritus) were rated according to severity by investigators at the visits and daily by patients. Eighty-three patients were randomized to placebo, 84 to 2.5 mg cetirizine, 85 to 5 mg cetirizine, and 76 to 10 mg cetirizine. Groups were comparable at inclusion. The primary efficacy variable was the percentage of days with no or only mild symptoms: at all doses, cetirizine appeared to be more effective than placebo, but a significant difference was reached only in the 10-mg group (difference in medians of 22%; P = 0.016). The test of linearity was significant (P = 0.026) for the percentage of asymptomatic days. The investigators' assessments at each visit scored the symptoms in the placebo group higher, i.e., more severe, than in the active groups, the 10-mg dose causing the greatest reduction in symptoms. Adverse events were infrequent and generally mild or moderate in severity. It was concluded that cetirizine at a 10-mg, once daily dose could be used to treat effectively 6-12-year-old children with perennial allergic rhinitis.