Procaterol metered aerosol in patients with chronic obstructive pulmonary disease.

The activity and tolerability of procaterol, a recently introduced beta 2-adrenergic drug, were evaluated in comparison with fenoterol and a placebo in a single blind, cross-over study, using a metered aerosol formulation. Twelve patients suffering from chronic obstructive pulmonary disease with reversible bronchial obstruction were enrolled. Before and 30, 120, 240, 360, 480 min after drug administration, forced vital capacity (FVC), forced expiratory volume at the first second, forced expiratory flow at 25-75% and 75-85% respectively of the FVC, thoracic gas volume and the specific airways conductance were calculated. Procaterol 20 mcg showed a significant bronchodilating activity as well as fenoterol 400 mcg. This activity was already significant within 30 min, achieved its maximum after two hours and lasted more than eight hours. Side-effects were complained of by 41% of patients treated with procaterol and by 50% treated with fenoterol; procaterol showed less cardiovascular effects than fenoterol.