Pentrinitrol is a metabolite of pentaerythritol tetranitrate. It has been introduced as an antianginal agent for man. Pentrinitrol decrease myocardial oxygen consumption and have a relatively long duration of action. The pharmacologic effects of pentrinitrol are similar to those of nitroglycerin. However, the duration of action of pentrinitrol is longer. Pentrinitrol produced lower pre-exercise systolic blood pressures and systolic blood pressures at point of angina. Pentrinitrol should permit patients to have fewer episodes of angina pectoris resulting from minor increases in physical activity. The same protection may also exist against angina pectoris produced by psychic stress. However, patients should still be cautioned against physical activity or psychic stress that ordinarily provokes angina pectoris.