Assessment of the bronchodilator effect of inhaled furosemide compared to salbutamol in asthmatic patients.

To compare the bronchodilator effects of high-dose inhaled furosemide, we studied 80 patients who were nonsmokers presenting some degree of bronchial obstruction. Of these patients, 40 were given salbutamol (1%) aerosol and the remaining 40 were given furosemide aerosol (100 mg). Respiratory functional tests were conducted at 10 min and 30 min, as well as measurement of pulse and blood pressure. Patients in the salbutamol group showed an improvement in forced expiratory volume (FEV1) of 7.9% at 10 min and 30 min, and the group given furosemide improved 6.9% (p > 0.05). Systolic blood pressure showed a slight increase of 2 mmHg in the salbutamol group and a decrease of 6 mmHg in the furosemide group (p < 0.05). The same occurred for diastolic blood pressure (p < 0.05). Pulse increased from 73.7 to 75.2 beats per min in the salbutamol group; however, in the furosemide group, pulse declined from 73.7 to 71.8 beats per min (p < 0.05). We conclude that furosemide at a dose of 100 mg has the same bronchodilator effect as salbutamol, as measured by FEV1 and forced expiratory flow of 25% to 75%. Furosemide was also related with a mild hypotensive effect and drop in pulse.