Efficacy and safety relative to placebo of an oral formulation of cetirizine and sustained-release pseudoephedrine in the management of nasal congestion.

Background: The aim of this study was to assess the clinical efficacy of an oral formulation of cetirizine 5 mg with sustained-release pseudoephedrine (PSE) 120 mg relative to placebo in patients with nasal congestion.

Methods: Twenty-four patients with perennial rhinitis due to house-dust-mite (HDM) allergy were recruited in this crossover study. A treatment period of 1 week, in which cetirizine/PSE was administered twice daily, was followed by a washout period of at least 2 weeks and a further period of 1 week in which the alternative treatment was given to each patient. Immediately after the first dose of each medication (day 1), nasal congestion and related symptoms were assessed during a 7-h challenge with HDM feces, with the Vienna Challenge Chamber (VCC), to investigate onset of action of the preparation. A second challenge of 3-h duration, carried out at least 12 h after the final dose, was undertaken after 1 week (mean) of twice-daily treatment to assess residual effects of the formulation after achievement of steady state.

Results: The oral formulation of cetirizine/PSE was significantly (P<0.001) superior to placebo in improving nasal obstruction during both challenges. The improvement in nasal airflow and nasal patency was significantly greater with cetirizine/PSE than with placebo (P<0.02). In addition, subjective assessment of nasal symptoms showed that cetirizine/PSE was significantly superior to placebo in both challenges for the sum of nasal obstruction scores (P<0.01). Both medications were well tolerated, and no serious adverse events occurred during the study.

Conclusions: In this study, cetirizine/PSE relieved nasal congestion and other objective and subjective symptoms to a significantly greater extent than placebo. No serious adverse events occurred, and both regimens were equally well tolerated.