Bronchodilator effect of Ipraterol on methacholine-induced bronchoconstriction in asthmatic patients

The addition of ipratropium, a synthetic cholinergic antagonist, to beta2-agonist therapy provides an additive improvement in adult with acute severe asthma and COPD because of increased vagal tone in the airways. We asked whether ipratropium in combination with fenoterol (Ipraterol) improved pulmonary function in comparison with original Berodual.

In order to determine the effects of nebulized a single dose of Ipraterol, the study was conducted in a double-blind, randomized and crossover manner by comparing the effect of nebulized a single dose of Berodual on methacholine-induced bronchoconstriction. The study consisted of an 1-week run-in phase and two study visits separated by a washout period of 7 days.

We studied 20 patients who ranged from 18 to 80 years of age and had mild to moderate persistent asthma.

Nebulized Ipraterol provided a rapid onset of bronchodilation effect similar to nebulized Berodual within 5 minutes by significantly increasing FEV, from 1.19 L to 1.73 L (p < 0.001) and from 1.19 to 1.69 L (p = 0.0001), respectively. This effect of Ipraterol lasted as long (up to 6 hours) and was similar to that of Berodual. The absolute FEV1 values at 360 min after Ipraterol treatment was still higher than the baseline values. We also found that there were no significant differences in the degree of improvement in FEV1 and hypokalemia following treatment with Ipraterol and Berodual.

Our data suggest that nebulized Ipraterol offers a statistically significant improvement in pulmonary function without significant systemic absorption causing hypokalemia, with the improvement being comparable to that achieved with nebulized Berodual.