Nitroglycerin is prescribed to prevent and treat angina pectoris (suffocating chest pain). This condition occurs when the coronary arteries become constricted and are not able to carry sufficient oxygen to the heart muscle. Nitroglycerin is thought to improve oxygen flow by relaxing the walls of arteries and veins, thus allowing them to dilate.

Nitroglycerin is used in different forms. As a patch or ointment, nitroglycerin may be applied to the skin. The patch and the ointment are for prevention of chest pain.

Swallowing nitroglycerin in capsule or tablet form also helps to prevent chest pain from occurring.

In the form of sublingual (held under the tongue) or buccal (held in the cheek) tablets, or in oral spray (sprayed on or under the tongue), nitroglycerin helps relieve chest pain that has already occurred. The spray can also prevent anginal pain. The type of nitroglycerin you use will depend on your condition.

The following section is intended to provide guidelines for taking nitroglycerin. Follow your doctor’s instructions carefully for using nitroglycerin in the form prescribed for you.