Nitroglycerin is a vasodilator, a medicine that opens blood vessels to improve blood flow. It is used to treat angina symptoms, such as chest pain or pressure, that happens when there is not enough blood flowing to the heart. To improve blood flow to the heart, nitroglycerin opens up (dilates) the arteries in the heart (coronary arteries), which improves symptoms and reduces how hard the heart has to work.
Nitroglycerin comes in quick-acting forms and long-acting forms.
If you have an irregular heartbeat (called an arrhythmia), your doctor might suggest a treatment called cardioversion to help get your heart back into a normal rhythm.
If your heart beats too fast or unevenly, it can be dangerous. Your heart may not be pumping enough blood to meet your body's needs. An irregular heartbeat also can lead to a stroke or a heart attack.
Quick-acting forms of nitroglycerin are used to relieve angina or used just before activities that typically cause angina. The quick-acting forms include tablets or oral sprays. The tablets are placed under the tongue (sublingual) or between the cheek and gum (buccal). The spray is used on or under the tongue. This topic covers these quick-acting forms of nitroglycerin.
Long-acting forms of nitroglycerin are used to prevent angina from happening. They are not used to stop sudden symptoms of angina. These long-acting forms include pills, tablets, skin ointment, and skin patches. This topic does not cover these long-acting forms of nitroglycerin.
Your doctor will prescribe the right amount for you. Do not use another person's nitroglycerin.
When do I use quick-acting nitroglycerin?
Your doctor will advise you when to use your nitroglycerin. In general, quick-acting nitroglycerin is used:
To relieve sudden angina.
Before stressful activities that can cause angina, such as walking uphill or having sexual intercourse.