Background: A combination metered-dose inhaler aerosol containing ipratropium bromide and albuterol sulfate has been reported to be more effective than either of its components in patients with chronic obstructive pulmonary disease. The dose of albuterol sulfate is equal in moles per liter to the dose of albuterol base used in the commercially available metered-dose inhalers.
Objective: To compare the safety and efficacy of the combination of ipratropium bromide and albuterol sulfate with a commonly prescribed albuterol metered-dose inhaler containing albuterol base alone.
Methods: Investigators at different sites performed a double-blind, 29-day trial involving 357 patients with chronic obstructive pulmonary disease. Efficacy measurements were taken at 15, 30, and 60 minutes after treatment with study medication and then hourly up to 6 hours on days 1 and 29 of the trial. The primary end point was improvement in forced expiratory volume in 1 second. Clinical status was followed up and safety monitoring was also performed.
Results: The combination produced a significantly greater peak and mean improvement in forced expiratory volume in 1 second over albuterol base alone on both test days. Similar changes were seen with forced vital capacity. Evaluations of clinical status were better for patients receiving combination therapy, and some improvements were statistically significant. The overall incidence of adverse effects was similar in the 2 treatment groups.
Conclusion: We conclude that a combination of ipratropium bromide and albuterol sulfate is more effective at improving pulmonary function than albuterol base alone, with no potentiation of adverse effects.