Bronchodilator activity of a new inhaled beta 2-adrenoceptor agonist, tulobuterol and its protective effect in exercise-induced asthma.

In fifteen patients with asthma tulobuterol, a new beta 2-adrenoceptor agonist, given by inhalation in 100 micrograms increments up to a cumulative dose of 600 micrograms produced dose related increases in both the FEV1 and FVC. The bronchodilation was observed within 5 min of the first dose. In a further nine patients tulobuterol 200 micrograms and 400 micrograms aerosol inhibited exercise-induced asthma following 6-8 min treadmill exercise and the effect was comparable to 200 micrograms salbutamol aerosol. Minor muscle tremors were observed in two patients with 400 micrograms of tulobuterol but no significant changes in pulse rate or blood pressure were noted.