Terbutaline and ephedrine in asthmatic children.

The effects of terbutaline, ephedrine, and placebo on the cardiovascular and pulmonary systems have been compared in 24 asthmatic children. Ephedrine and terbutaline were both found to be effective bronchodilators, with onset of action within 30 minutes. The bronchodilator effect of ephedrine was maintained for three hours, while terbutaline was active for five hours. Terbutaline caused significantly greater improvement in pulmonary functions than did ephedrine. Both terbutaline and ephedrine were associated with clinically insignificant changes in blood pressure and pulse rate. The only significant side effect observed was hand tremor in children receiving terbutaline and this appeared only early in the course of drug treatment. There was no evidence of tolerance to the bronchodilator effect of ephedrine or terbutaline after eight weeks of therapy.