Actions of salbutamol, disodium cromoglycate, and placebo administered as aerosols in acute asthma.

Abstract

The effects on the peak expiratory flow rate of the drug sequences, placebo-salbutamol-disodium cromoglycate and placebo-disodium cromoglycate-salbutamol administered via a nebulizer were examined in 35 children with asthma. Twenty children were each examined once within 4 h of admission to hospital with an acute attack of asthma and the remaining 15 children were examined later in the attack on 2 occasions. The placebo effect of sterile water accounted for about half of the total bronchodilator action both early and late in the attack. This effect may be due to the action of water on the surface film of surfactant, causing collapse of bubbles and strands or webs of mucoid material, thus decreasing airways resistance. At this time salbutamol is significantly more potent than disodium cromoglycate as a bronchodilator agent.