Effects of Pranlukast Hydrate on Airway Hyperresponsiveness in Non-Asthmatic Patients with Japanese Cedar Pollinosis

Abstract

Recent studies have suggested that allergic rhinitis is closely related to bronchial asthma, reflecting the "one airway-one disease" hypothesis. It is unclear if the effects of pranlukast, a leukotriene-receptor antagonist, are consistent with this hypothesis. The goal of the study was to determine if pranlukast has effects on the upper and lower airways through a comparison of the effects of fexofenadine and pranlukast on airway hyperresponsiveness in non-asthmatic patients with cedar pollinosis before the Japanese cedar pollen season and during the peak pollen season. Patients received fexofenadine hydrochloride plus oral mequitazine (fexofenadine group) or pranlukast hydrate plus oral mequitazine (pranlukast group) as an initial treatment. Subsequent changes in airway responsiveness to acetylcholine were measured. Among patients in whom coughing developed during the peak pollen season, airway responsiveness significantly increased in the fexofenadine group. In the pranlukast group, airway responsiveness did not increase significantly, regardless of the presence or absence of coughing. The results indicate that pranlukast hydrate inhibits airway hyperresponsiveness in non-asthmatic patients with Japanese cedar pollinosis. In turn, this suggests that cysteinyl leukotrienes have a role in increased airway responsiveness.