We investigated the efficacy of local ipratropium bromide on methacholine-induced nasal secretions in a double-blind, placebo-controlled experiment. Twenty subjects with perennial rhinitis received a total intranasal dose of 21, 42, 84, and 168 micrograms of ipratropium bromide or placebo in each nostril. One hour later, filter paper disks were used to deliver increasing doses of methacholine and to collect secretions from the left septum. Concomitantly, symptoms of rhinorrhea and nasal congestion were scored. Compared with doses of placebo, all doses of ipratropium bromide significantly reduced the methacholine-induced increase in nasal secretion weights and symptoms of rhinorrhea (p less than 0.01). The highest dose was significantly more effective than the lower doses in reducing secretion weights (p = 0.01). We speculate that ipratropium bromide may prove beneficial for the treatment of rhinorrhea in perennial rhinitis. Furthermore, increasing the delivered dose to 168 micrograms may increase efficacy without augmenting side effects.