A time-dose study of the effect of topical ipratropium bromide on methacholine-induced rhinorrhoea in patients with perennial non-allergic rhinitis.

Intranasal application of the anticholinergic drug, ipratropium bromide, is used for the treatment of watery rhinorrhoea. We have performed a time-dose study of ipratropium bromide in patients with perennial non-allergic rhinitis, using rhinorrhoea, induced by nasal methacholine challenge, as a laboratory model. Two doses of ipratropium bromide, 40 microg and 80 microg, delivered from a pressurized aerosol, were both very effective, reducing the volume of methacholine-induced secretion by 85 to 95%. The maximum effect lasted for at least 4 h and then slowly diminished. A significant effect was demonstrable for 12 h with 40 microg and for 18 h with 80 microg ipratropium bromide. These results from a laboratory challenge study indicate that the presently used frequency of ipratropium bromide, namely four times daily, may not be necessary in many patients. Perhaps once in the morning, followed by an as-needed medication, will be a better way to use intranasal ipratropium bromide in perennial non-allergic rhinitis.