The health-related quality of life effects of once-daily cetirizine HCl in patients with seasonal allergic rhinitis: a randomized double-blind, placebo-controlled trial

Summary Background Seasonal allergic rhinitis (SAR) is characterized by subjectively irritating symptoms that can have a substantial impact on the patient's health‐related quality of life (HRQL), adversely affecting physical and social or work activity, interpersonal relationships, and general psychological well‐being. The objective of this study was to test the effect of cetirizine HCl 10 mg once daily on the HRQL of adult patients 18–65 years of age with SAR, concurrently assessing safety and efficacy. Methods Randomized double‐blind, placebo‐controlled, parallel group trial conducted during the 1999 spring SAR season at 19 centers in the US. Following a 1‐week placebo run‐in period, qualified patients were randomized to cetirizine 10 mg, or placebo once daily for a 2‐week treatment period. Change in Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) and Total Symptom Severity Complex (TSSC) scores from baseline were the primary outcomes of interest. Results Of the 611 patients enrolled, 403 (66%) were randomized. Cetirizine‐treated patients reported significantly greater improvement in overall HRQL (P