Background: Levalbuterol, the R-isomer of albuterol, has advantages over racemic albuterol in asthma; however, the effectiveness of this beta-agonist in COPD has received little attention.
Objectives: To evaluate the effectiveness of a single dose of nebulized levalbuterol in COPD.
Design: A randomized, double-blind, placebo-controlled trial comparing nebulized levalbuterol to racemic albuterol, combined racemic albuterol and ipratropium, and placebo.
Patients: Thirty patients with stable COPD (FEV(1) between 45% and 70% of predicted) were studied.
Methods: After withholding usual bronchodilator medications for appropriate washout periods, patients were randomized on separate visits to receive single doses of each the following nebulized bronchodilator medications: (1) levalbuterol, 1.25 mg; (2) racemic albuterol, 2.5 mg; (3) combined racemic albuterol, 2.5 mg, and ipratropium, 0.5 mg; or (4) placebo. FEV(1), FVC, pulse rate, and oxygen saturation were measured at baseline, 0.5 h following nebulization, and hourly for 6 h. Hand tremor, using a 7-point scale, was measured at baseline, 0.5 h, 1 h, and 2 h. Treatment-placebo differences were analyzed using repeated-measures analysis of variance and least-squares means.
Results: The mean age (+/- SD) of patients was 69 +/- 15 years. Mean FEV(1) was 1.15 +/- 0.49 L. By 0.5 h following study drug administration, all three nebulized bronchodilator treatments led to similar, significant improvements in FEV(1) compared to placebo. These effects persisted at 1 h and 2 h for all three treatments; however, by 3 h, only the combined albuterol/ipratropium group had a mean change in FEV(1) significantly greater than placebo. There were no significant differences between bronchodilator groups at any time period. A mild increase in pulse rate was observed in all treatment groups. There were no significant treatment-placebo differences in oxygen saturation or hand tremor.
Conclusion: For single-dose, as-needed use in COPD, there appears to be no advantage in using levalbuterol over conventional nebulized bronchodilators.