BACKGROUND: The nose and bronchi are closely linked, and rhinitis often precedes the onset of asthma. Bronchial obstruction is a characteristic of asthma, and demonstration of its reversibility is a key element in diagnosis. However, reversibility testing requires a spirometer, which is rarely available in the doctor's office. Visual analog scales (VAS) are frequently used in daily practice. OBJECTIVE: This study evaluated the suitability of a VAS for assessing bronchodilation in patients with persistent allergic rhinitis as a means of selecting candidates for screening spirometry. METHODS: We evaluated 120 patients with moderate to severe persistent allergic rhinitis. All patients underwent a clinical examination, skin prick test, spirometry, bronchodilation test, and VAS. RESULTS: Patients with rhinitis showed significantly increased forced expiratory volume in the first second (FEV1) after the bronchodilation test (median, 11.5%). Positive results were observed in 60%, and VAS values increased (>30%) after the test. There was a significant relationship between deltaVAS and deltaFEV1 (P<.0001; r=0.482). CONCLUSION: This preliminary study shows that patients with moderate to severe persistent allergic rhinitis often experience an increase in FEV1 after the bronchodilation test. VAS assessment of the test might be useful when selecting candidates for spirometry for possible bronchial involvement.