EFFECT OF A CALCIUM-ANTAGONIST, NIFEDIPINE, IN EXERCISE-INDUCED ASTHMA

The nifedipine effect was studied in 8 extrinsic asthmatic subjects with exercise-induced asthma. Before the exercise the patients received, in a randomized double-blind manner, either 20 mg nifedipine, sublingually or sodium cromoglycate by inhalation on 2 separate days. Nifedipine and sodium cromoglycate in all patients inhibited the exercise fall in FEV1 [forced expiratory volume in 1 s]. No differences were found between the 2 drugs. Nifedipine is a potent antagonist of Ca ion influx in smooth muscle and secretory cells. Evidently, it may inhibit release of mast cell mediators and reduce bronchial smooth muscle contractility in asthma.