Effect of ipratropium bromide versus metaproterenol in patients with COPD without asthma or atopy

Mean percentage changes in FEV₁ at serial times after inhalation of ipratropium bromide (40 mcg) or metaproterenol (1500 mcg) on day 90 of the 90 day trial period of daily drug administration. Ipratropium was more potent at the peak of its effect and was longer acting than the adrenergic agent. Similar results were demonstrated on days 1 and 45 (not shown).