Oral terbutaline sulfate--amelioration of exercise-induced bronchospasm.

Bronchospasm can be induced in asthmatics when exercised according to a multistage branching treadmill protocol that allows them to achieve 80 per cent of their age-predicted maximal heart rate. This present study was undertaken to investigate the effect of oral terbutaline sulfate in ameliorating exercise-induced bronchospasm. Ten asthmatics were exercised, and FEV1.0 and MMEFR were assessed while standing, using a Jones Pulmonar II waterless spirometer at 5, 15, and 30 minutes after exercise. Three hours before exercise, the subjects received no medication, oral placebo, or 5 mg terbutaline sulfate orally. At all time intervals after exercise, the pulmonary function of the group pretreated with oral terbutaline was superior when compared to the no-medication group (P less than 0.01) and to the placebo-treated group (P less than 0.05). Oral terbutaline appeared to normalize the exercise tolerance of the asthmatics and restore physiologic pulmonary airway conductance by the parameters of FEV1.0 and MMEFR.