Tiotropium: an inhaled, long-acting anticholinergic drug for chronic obstructive pulmonary disease.

Inhaled anticholinergic drugs are considered one of the principal bronchodilator treatments for chronic obstructive pulmonary disease (COPD). Ipratropium bromide is an anticholinergic drug frequently administered for the treatment of COPD. Unfortunately, ipratropium has a short duration of action, requiring administration every 6 hours; this regimen affects adherence to drug therapy.