A comparison between fenoterol/ipratropium bromide combinations and salbutamol administered as nebulizer solutions assessing dose-response and duration of action.

A double-blind, randomized crossover trial was carried out in 10 patients with reversible airways obstruction to assess dose-response and duration of action of 0.5 mg ipratropium combined with 1.25 mg, 2.5 mg or 5.0 mg fenoterol compared with 5.0 mg salbutamol given alone. Each solution was nebulized from a volume of 4 ml and administered via a mouth-piece at approximately the same time on each of 4 test days. Measurements were made of FEV1, FVC and PEFR before and at intervals after nebulization. The results showed that each dose of the combination produced greater improvements in the lung function parameters than did salbutamol alone and the degree of response was proportional to the dose of the combination. No significant treatment differences were recorded in systolic or diastolic blood pressure between any of the treatments, but the combined preparations produced significantly higher pulse rates than did salbutamol.