Ephedrine therapy in asthmatic children. Clinical tolerance and absence of side effects.

Sixteen asthmatic children between the ages of 7 and 13 years, 13 of whom were receiving theophylline orally around-the-clock, were studied for eight weeks in double-blind manner to evaluate efficacy, toxicity, and development of tolerance to the combination of ephedrine sulfate and theophylline. Reactions to the drug combination, assessed by close observation and daily patient questioning by the nursing staff, showed no toxicity or substantial side effects. Pulmonary function was measured hourly for six hours after each morning dose, and the data were analyzed to determine the degree and duration of bronchodilator response. Comparison of data from weeks 1 and 8 showed no evidence of the development of tolerance. Ephedrine is a potent bronchodilator that, in appropriate doses, can be administered safely along with therapeutic doses of theophylline without fear of progressive tolerance or toxicity.