Effect of Inhaled Furosemide on the Bronchial Response to Lysine-Aspirin Inhalation in Asthmatic Subjects

Abstract

It has been demonstrated recently that inhaled furosemide inhibits bronchoconstriction induced by cold air, physical exercise, various antigens, and metabisulfite. The goal of the present study was to determine if the inhalation of furosemide would inhibit the bronchoconstriction resulting from the inhalation of lysine-aspirin in aspirin-sensitive asthmatics. Six female subjects with known hypersensitivity to aspirin participated in this crossover study comparing 20 mg of inhaled furosemide and placebo. The volunteers inhaled increasing concentrations of lysine-aspirin after the inhalation of furosemide or placebo. The geometric mean provocative dose causing a 20 percent decrease in the FEV1 (PD20) after the inhalation of placebo was 30.4 mg/ml and the PD20 was equal or below 90 mg/ml in all patients. In contrast, the FEV1 did not decrease by 20 percent in any of the patients pretreated with furosemide when the inhaled concentration was increased to 360 mg/ml. From this study, we conclude that the administration of furosemide blocks the bronchospasm induced by the inhalation of lysine-aspirin in aspirin-sensitive asthmatics.