Comparison of two calcium antagonists, verapamil and gallopamil (D-600), in exercise-induced asthma.

The effect of inhaled verapamil and gallopamil (estimated dose 3 mg) was studied in 10 patients with exercise-induced asthma. Saline was used as a control. Verapamil and gallopamil modified exercise-induced asthma in 8 of the 10 patients and the degree of inhibition with both the drugs was comparable. Gallopamil, which is a more potent vascular smooth muscle calcium antagonist when compared to verapamil, failed to show a greater protective effect in exercise-induced asthma in the patients studied.