A randomized, double-blind, parallel-group study to compare the efficacy and safety of a once-daily loratadine–pseudoephedrine combination with that of a twice-daily loratadine–pseudoephedrine combination in the treatment of allergic rhinitis

The aim of this study is to compare the efficacy and safety of a once-daily loratadine–pseudoephedrine sustained release tablet with that of a twice-daily loratadine–pseudoephedrine in the treatment of patients with allergic rhinitis. Forty-eight subjects were randomized into either the treatment or control group. The efficacy endpoint was assessed by total symptom scores (TSS). And the results were analyzed by non-inferiority testing and t-tests. Non-inferiority testing of the once daily loratadine 10 mg–pseudoephedrine 240 mg sustained release tablets to the twice-daily loratadine 5 mg–pseudoephedrine 120 mg combination tablets was not supported by statistical significance. However, both the treatment and control groups showed a significant reduction from the baseline in TSS (P < 0.05), and the difference between groups did not reach statistical significance (P > 0.05). In conclusion, once-daily and twice-daily preparations of loratadine–pseudoephedrine were comparable in efficacy and safety in the treatment of allergic rhinitis.