Prolonged effect of inhaled glycopyrrolate in asthma.

Glycopyrrolate, a quaternary ammonium anticholinergic compound is a potentially useful bronchodilator. To determine the efficacy, optimal dose, and duration of action of inhaled glycopyrrolate, we gave the drug to 11 asthmatic patients. Each subject received placebo or glycopyrrolate (100, 200, 600, or 1,200 micrograms) by inhalation in a double-blind, randomized, crossover design. Measurements included FEV1, FVC, heart rate, and blood pressure before administration of the drug and periodically for 12 hours. For eight hours following all doses of glycopyrrolate, both FEV1 and FVC (both as percent of predicted) were significantly greater for drug than for placebo. Glycopyrrolate may be a useful long-acting drug for the treatment of asthma.