Establishing a model of seasonal allergic rhinitis and demonstrating dose-response to a topical glucocorticosteroid.

Background: Symptoms of seasonal allergic rhinitis may vary greatly. Hence, for research purposes, there is a need for disease-like models of allergic rhinitis. In a preliminary study, involving 7 days' challenge with allergen, promising symptom consistency was obtained and dose-response to a glucocorticosteroid could, in part, be demonstrated.

Objective: To establish this model of seasonal allergic rhinitis and test the hypothesis that mometasone furoate is more potent than budesonide as an antirhinitis drug.

Methods: Thirty-eight patients with seasonal allergic rhinitis received treatment with spray-formulations of placebo, budesonide 64 microg, budesonide 256 microg, and mometasone furoate 200 microg in a double-blind, crossover design. After 3 days' treatment, individualized nasal allergen-challenges were administered daily for 7 days while the treatment continued. Nasal symptoms and peak inspiratory flow (PIF) were recorded.

Results: During the last 3 days of allergen challenge without active treatment, consistent around-the-clock symptoms were recorded and recordings during these days were used in the analysis. With few exceptions the active treatments reduced nasal symptoms and improved nasal PIF (P values <0.001 to 0.05). Budesonide caused dose-dependent improvements in evening symptoms, morning nasal PIF, and nasal PIF recorded 10 minutes after allergen-challenge (P values <0.05). Budesonide 256 microg produced greater improvement than mometasone furoate 200 microg for nasal PIF 10 minutes after allergen-challenge (P < 0.05).

Conclusion: The present allergen challenge method, producing consistent symptoms and nasal PIF data, emerges as a model of seasonal allergic rhinitis well suited for exploring potency and efficacy of drug intervention. The present data do not support the view that mometasone furoate is a more potent antirhinitis drug than budesonide.