Incremental benefit of adding oxitropium bromide to formoterol in patients with stable COPD.

The effects of the long-acting beta(2)-agonist formoterol, the anticholinergic drug oxitropium bromide, and their combination were compared in 16 patients with partially reversible stable COPD. On each of 4 study days patients inhaled both drugs separated by 180 min in alternate sequence, with formoterol being administered in two doses (formoterol 12 mu g + oxitropium bromide 200 mu g; oxitropium bromide 200 mu g + formoterol 12 pg; formoterol 24 mu g + oxitropium bromide 200 pg; oxitropium bromide 200 mu g + formoterol 24 mu g). FEV1 and FVC were measured baseline and after 30, 60, 120, 180, 210, 240, 300 and 360 min. In terms of onset of action, formoterol performed better than oxitropium bromide. Within the first 180 min after inhalation formoterol 24 mu g was the most effective drug (maximal change in FEV1: formoterol 24 mu g = 25.6%, formoterol 12 mu g = 21.1%, oxitropium bromide = 18.2%). Increased bronchodilation was obtained when the second drug was added, the sequence formoterol 24 mu g + oxitropium bromide being the most effective (maximal change in FEV1 over baseline: formoterol 24 mu g + oxitropium bromide 28.8%, oxitropium bromide + formoterol 24 mu g 20.9%, formoterol 12 mu g + oxitropium bromide 26.6%, oxitropium bromide + formoterol 12 mu g 22.5%). Significant improvement in pulmonary function may be achieved by giving two different bronchodilators in stable COPD patients. The sequence formoterol 24 mu g + oxitropium bromide 200 mu g seems to be the most effective. (C) 1999 Academic Press.