Domiciliary measurement of nasal peak inspiratory flow rate (nPIFR) provides a simple, noninvasive, objective assessment of nasal patency and may be useful for determining the effectiveness of therapeutic interventions. This randomized, parallel-group, investigator-blind study compared the effects of triamcinolone acetonide aqueous nasal spray (TAA AQ), 220 microg everyday (n = 19), and fluticasone propionate (FP AQ), 200 microg everyday (n = 20), for 21 days on nasal airflow in patients with seasonal allergic rhinitis (SAR), using domiciliary nPIFR. Patients had a > or = 2-year history of springtime SAR and positive epicutaneous or intradermal test to grass, tree pollen, or outdoor molds. nPIFR was measured three times each morning (before dosing) and at bedtime using an In-Check nPIF meter. All measurements were recorded on diary cards, and the best of the three measurements was used for data analysis. There were no significant demographic differences between treatment groups at baseline. Baseline nPIFR (+/- SE) was 106.5 L/minute (+/- 51.2) and 97.7 L/minute (+/- 45.0) in the TAA AQ and FP AQ groups, respectively (p = 0.5733). Model-based estimation of mean change from baseline with TAA AQ and FP AQ at the end of the study were 21.72 (+/- 6.04) and 16.48 (+/- 5.73), respectively. Both treatment groups showed an approximately 20% improvement in nPIFR versus baseline (p = 0.0002 and p = 0.0069 for TAA AQ and FP AQ, respectively), with no statistical difference between treatments. Weekly mean nPIFR scores indicated progressive improvement in nasal airflow with both treatments. Both TAA AQ and FP AQ were effective for improving nasal airflow as indicated by increases in nPIFR in patients with SAR.