A trial was designed to assess whether repeated administration of ipratropium bromide for two weeks produced greater improvement than was obtained after a single dose. The effect of ipratropium bromide was compared with that of a placebo during a double-blind cross-over randomized trial in patients with advanced chronic airways disease in a stable state. Ipratropium bromide and placebo were both administered by metered dose inhaler for 14 days. There was a slight statistically significant improvement of conductance, thoracic gas volume, FEV1 and VC after inhalation of ipratropium bromide, but repeated doses of the drug did not produce progressive improvement.