Medical therapy of Prinzmetal's variant angina.

Medical therapy for Prinzmetal's variant angina has been treatment of the acute attack with sublingual nitroglycerin. Prophylactic therapy has been more difficult, utilizing long-acting vasodilators that are limited because of their short half-life and side effects when therapeutic doses are used. Alpha-adrenergic blockade has been effective in some patients but is frequently associated with intolerable side effects or apparent development of tolerance to the drug. Preliminary experience from a randomized double-blind trial of diltiazem, a new calcium antagonist, has demonstrated a 90% reduction in pain episodes, with many patients becoming pain-free on the 240-mg daily dose. These data and the lack of adverse side effects demonstrate a dramatically effective therapy for patients with coronary artery spasm.