Lack of Cardiac Effect from Repeated Doses of Albuterol Aerosol

Abstract

To simulate the pattern of use by some patients at home, we studied the effect of frequently repeated inhalation of albuterol aerosol on cardiac rhythm. Fifteen stable outpatient asthmatic children, ages 9-14 years were treated with two puffs of albuterol aerosol (180 mcg) followed either by hourly placebo or hourly albuterol aerosol for 5 hours (10 puffs = 900 mcg) in a randomized, double-blind crossover study. Cardiac rhythm was Holter monitored and pulmonary function was tested hourly for 5 hours. Heart rate (HR) was analyzed at hourly intervals. Pretreatment heart rate of 95.4 bpm ±1.9 SEM declined by 0.4-3 (bpm) after single dose and declined by 2.2-5.6 (bpm) from 99.2 (bpm) ± 2.3 SEM during multiple doses. No one developed arrhythmia, and side effects were infrequent on either day. Forced expiratory volume in 1 second (FEV1) increased similarly on both regimens. It remained stably elevated on the multiple doses, but it started to decline at 120 minutes after the single dose. Our study shows a substantial margin of safety in administration of albuterol aerosol to asthmatic children.