Antianginal effects of pentaerythritol tetranitrate

31 patients with confirmed angina pectoris and selected to form an homogenous group entered this double-blind study. Following a period of observation during which the patients were on a placebo and only took nitroglycerin to relieve pain, a randomized treatment of either dipyramidole (DPM) 75 mg or pentaerythritol tetranitrate (PETN) 80 mg 8-hourly was given during 4 weeks. At the end of this period the anti-anginal effects of the drugs were assessed, using the following criteria: incidence of anginal attacks, nitroglycerin consumption, number of attacks per days, changes in exercise capacity and changes in repolarization on ECG. PETN proved distinctly more effective than DPM. The number of attacks per week decreased from 11.5 to 1.5 under PETN and from 12.5 to 9 under DPM. Similarly, nitroglycerin weekly consumption fell from 8 to 1.5 tablets under PETN and from 9 to 7 tablets under DPM.