Intranasal fluorocarbon anticholinergic agents have been used to treat the nasal hypersecretion of perennial non-allergic rhinitis, but chronic use has been restricted either due to the potential for systemic anticholinergic adverse events or due to the irritating properties of the fluorocarbon metered dose formulations. This study evaluates a new aqueous nasal formulation of ipratropium bromide (Atrovent Nasal Spray 0.03%) in subjects with perennial non-allergic rhinitis in a double-blind, placebo-controlled trial. Two hundred and twenty-eight patients were randomized to receive two sprays per nostril of either ipratropium bromide (42 micrograms/nostril) or placebo-administered three times a day as an aqueous nasal spray over an 8-week interval. Patients were evaluated bi-weekly and maintained daily diaries for duration and severity of nasal symptoms. Ipratropium bromide reduced the mean severity and duration of rhinorrhoea within the first week and throughout the 8 weeks of active treatment compared with placebo (P < 0.05). Secondary endpoints of efficacy (patient and physician global assessments and a quality of life assessment) also supported the use of ipratropium bromide nasal spray for rhinitis symptom control. With the reduction in rhinorrhoea by the ipratropium bromide nasal spray, patients reported a marked improvement in daily moods vs placebo (P < 0.01). Both placebo and ipratropium bromide nasal spray induced a modest reduction of nasal congestion, sneezing and postnasal drip. This improvement in these other nasal symptoms was consistent with the known soothing effects of a nasal saline vehicle. There were no drug-related serious or systemic anticholinergic adverse events.(ABSTRACT TRUNCATED AT 250 WORDS)