Abstract
The effect of nifedipine was studied in 15 patients with exercise-induced asthma. Nifedipine inhibited the exercise-induced fall in FEV1 [forced expiratory volume in 1 s] almost completely in 4 patients, offered partial protection in 9 patients and had no effect in the remaining 2 patients. Mediator release which is dependent on free Ca ions may play an important role in exercise-induced asthma and Ca antagonists may inhibit post-exercise bronchoconstriction by their blocking effect on Ca channels of the mast cells.