[Possibility of developing tolerance to the antianginal effect of verapamil]

Ten patients with ischemic heart disease and stable angina of effort have been examined for the possibility of tolerance development to verapamil antianginal effect, which was assessed using bicycle ergometry. Antianginal effect after the course of treatment with 80 mg of verapamil 3-4 times per day, and 120 mg of verapamil 3-4 times per day, was significantly more pronounced than after single administration of 80 and 120 mg of the drug. Thus, no tolerance to verapamil antianginal effect was observed during the course of treatment with verapamil, moreover the effect was enhanced.