Objective: To assess the efficacy and onset of action of azelastine nasal spray and desloratadine tablets in patients with allergen-induced seasonal allergic rhinitis (SAR).
Research Design And Methods: 46 adult patients with a history of SAR were exposed to a controlled grass pollen concentration for 6 h in the Vienna Challenge Chamber (VCC) in each treatment period according to a randomised, double-blind (double-dummy), three-period, three-sequence crossover design (wash-out period of 12 days). Single doses of study medication (one puff nasal spray into each nostril of azelastine, 0.