Fexofenadine hydrochloride, 180 mg, exhibits equivalent efficacy to cetirizine, 10 mg, with less drowsiness in patients with moderate-to-severe seasonal allergic rhinitis

Previous studies have shown that fexofenadine and cetirizine effectively relieve symptoms of seasonal allergic rhinitis (SAR). To compare the effects of fexofenadine hydrochloride, 180 mg, and cetirizine, 10 mg, on symptoms, drowsiness, and motivation in patients with moderate-to-severe SAR. In this 2-week multicenter, double-blind, randomized study, 495 subjects with moderate-to-severe SAR received once-daily fexofenadine hydrochloride, 180 mg, or cetirizine, 10 mg, without regard to food intake. Daily 12-hour reflective (am, pm) and instantaneous (am) individual symptoms and total symptom score (TSS) were evaluated. Drowsiness and motivation were recorded daily using visual analog scale at 7 am, 10 am, and 3 pm. Between-treatment differences in reduction from baseline in am instantaneous and 24-hour reflective TSS were −0.18 [95% confidence interval (CI), −0.55 to 0.20) and −0.22 (95% CI, −0.59 to 0.15), respectively. Since CIs for reduction in TSS between treatments fell within a 0.7 margin (defined a priori), treatments were considered statistically equivalent. Patients receiving fexofenadine experienced significantly less overall drowsiness vs baseline than those receiving cetirizine [−2.33 (95% CI, −3.80 to 0.86) vs 0.37 (95% CI, −1.10 to 1.84), P = .0110]. There was a trend toward greater improvements in overall motivation with fexofenadine compared with cetirizine [−2.36 (95% CI, −3.83 to 0.90) vs −0.30 (95% CI, −1.76 to 1.17), P = .0504]. Once-daily fexofenadine hydrochloride, 180 mg, given for 2 weeks caused statistically and clinically equivalent improvement in symptoms and significantly less drowsiness va baseline, compared with cetirizine, 10 mg, in patients with moderate-to-severe SAR.