Bronchodilatory effect of inhaled versus oral salbutamol in bronchial asthma.

The bronchodilator effect of salbutamol inhalation was compared with the oral administration of the drug in 10 patients with bronchial asthma. The study consisted of treating each patient for 4 consecutive days with: (1) a combined regimen consisting of a 2-mg tablet of salbutamol and 10 puffs of salbutamol inhalation (100 micrograms in each puff) given in pairs of two puffs every 20 min (regimen 1); (2) salbutamol inhalation (regimen 2); (3) salbutamol tablet (regimen 3), and (4) placebo, tablet and inhalation (regimen 4). The bronchodilator effect was assessed measuring the forced expiratory volume in 1 s, the forced vital capacity and the peak expiratory flow rate. The bronchodilator response was significantly greater on the inhalation alone and the combined regimen than on the oral and placebo regimens. The combined regimen showed a better although not significant bronchodilatory response than the inhalation regimen. We conclude that the inhalation treatment with salbutamol is superior to the oral route of administration in treating bronchial asthma and that the oral treatment has an added effect.