Nitroglycerin, a fast-acting vasodilator, is commonly used as a first-line agent for angina in the emergency department and to manage chest pain due to acute coronary syndromes. It is also a treatment option for other disease states such as acute heart failure, pulmonary edema, and aortic dissection. Nitroglycerin is converted to nitric oxide, a potent vasodilator, in the body, leading to venodilation at lower dosages and arteriodilation at higher dosages that results in both preload and afterload reduction, respectively. Although nitroglycerin has historically been administered as a sublingual tablet and/or spray, it is often given intravenously in the emergency department as this enables titration to effect with predictable pharmacokinetics. In this review article, we outline the indications, mechanism of action, contraindications, and adverse effects of nitroglycerin as well as review relevant literature and make general recommendations regarding the use of nitroglycerin in the emergency department.