Formoterol for acute asthma in the emergency department: a systematic review with meta-analysis

Background Although several published studies have suggested that formoterol fumarate could be equivalent to short-acting β2-agonists (SABAs) for the treatment of asthma exacerbations, its role in acute asthma treatment remains undefined. Objective To evaluate the efficacy and safety of inhaled formoterol (compared with SABAs) for the emergency department treatment of patients with acute asthma. Methods Systematic searches were conducted in MEDLINE, EMBASE, the Cochrane Controlled Trials Register, and manufactures' trial registers, without language restriction. The primary outcomes were spirometric measures. The secondary outcomes included final serum potassium level, heart rate, electrocardiographic QT interval corrected for heart rate, and total withdrawals. Results Nine randomized controlled trials (including 576 participants) were selected. No significant difference could be detected between formoterol and SABAs for any of the selected time points: at 30 to 40 minutes after the first administration of study drugs (standardized mean difference, −0.19; 95% confidence interval, −0.56 to 0.17; I2 =75%), at the end of treatment (standardized mean difference, −0.25; 95% confidence interval, −0.72 to 0.13; I2 =89%), and at 60 to 90 minutes after the last dose (standardized mean difference, −0.13; 95% confidence interval, −0.55 to 0.28; I2 =80%). Similarly, there were no significant differences between formoterol and SABAs regarding final serum potassium level, heart rate, QT interval, hospitalization rate, and total withdrawals. Conclusions This review suggests that high-dose formoterol administered via dry powder inhaler is well tolerated and provides rapid and effective bronchodilation, similar to high-dose salbutamol or terbutaline via metered-dose inhaler or nebulizer. Formoterol may be used in the treatment of acute asthma in the emergency department setting.