Objective: The objective of this study was to evaluate montelukast 10 mg daily as treatment for allergic rhinitis in patients with symptomatic allergic rhinitis and active asthma during the allergy season.

Methods: This was a multicenter study of 831 patients (ages 15 years-85 years) with seasonal allergen sensitivity, active symptoms of seasonal allergic rhinitis, and active asthma. Following a single-blind, placebo run-in period of 3 days-5 days, patients were randomized to oral montelukast 10 mg (n = 415) or placebo (n = 416) daily during the 2-week, double-blind, active-treatment period.

Main outcome measures: The primary endpoint was Daily Rhinitis Symptoms score, average of Daytime Nasal Symptoms and Nighttime Symptoms, as self-rated by patients on a 0-3 scale on daily diaries.

Results: Montelukast reduced the Daily Rhinitis Symptoms score: difference between montelukast and placebo in mean change from baseline was -0.12 [95% CI -0.18, -0.06; p < or = 0.001]. Similar improvements were seen in Daytime Nasal Symptoms (-0.14 [-0.21, -0.07; p < or = 0.001]) and Nighttime Symptoms (-0.10 [-0.16, -0.04; p < or = 0.001]). Improvements (p < 0.05) were seen in Daytime Eye Symptoms and in the secondary endpoints of Global Evaluations of AR by Patient and by Physician, and Rhinoconjunctivitis Quality of Life. In exploratory analyses, improvement in rhinitis symptoms was numerically (though not statistically) larger in patients with greater levels of asthma at study start. Montelukast provided benefit in the Global Evaluations of Asthma by Patient and by Physician: mean differences were -0.24 [-0.41, -0.06; p = 0.008] and -0.17 [-0.33, -0.01; p = 0.037]. Similarly, as-needed beta-agonist use (puffs/day) was reduced with montelukast (p < or = 0.005).

Conclusion: Montelukast provides significant relief from symptoms of seasonal allergic rhinitis, while also conferring a benefit for asthma, in patients with both allergic rhinitis and asthma.