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Nitroglycerin, isosorbide dinitrate, isosorbide mononitrate, and amyl nitrite are the principal agents covered. Nitrates release nitric oxide, increasing cGMP and relaxing vascular smooth muscle. Venodilation predominates, lowering preload, left ventricular wall stress, and myocardial oxygen demand; higher doses also produce arterial dilation. Nitrates dilate large epicardial coronary arteries and can relieve coronary spasm, including in variant angina. Rapid hepatic first-pass metabolism shapes the available routes, while tolerance may develop and requires attention to a daily nitrate-free interval. Common adverse effects include headache, flushing, hypotension, and reflex tachycardia. The topic also addresses interactions that can cause severe hypotension, patient counseling, monitoring, storage, and management of overdose.