Medically reviewed on February 14, 2017
What is nitroglycerin?
Nitroglycerin is a nitrate that dilates (widens) blood vessels, making it easier for blood to flow through them and easier for the heart to pump.
Nitroglycerin is used to treat or prevent attacks of chest pain (angina).
Nitroglycerin may also be used for purposes not listed in this medication guide.
You should not use nitroglycerin if you are also using medicine to treat pulmonary arterial hypertension (PAH). Do not take erectile dysfunction medicine (Viagra, Cialis, Levitra and others) while you are taking nitroglycerin.
You should not use sublingual nitroglycerin if you have severe anemia, increased pressure inside your skull, or symptoms of circulation problems or shock (pale skin, cold sweat, irregular heartbeats, sudden weakness or feeling like you might pass out).
Seek emergency medical attention if you have early symptoms of a heart attack (chest pain or pressure, pain spreading to your jaw or shoulder, sweating, general ill feeling).
Before taking this medicine
You should not use nitroglycerin if you are allergic to it, or if you are using medicine to treat pulmonary arterial hypertension (PAH), such as riociguat (Adempas), sildenafil (Revatio), or tadalafil (Adcirca).
Do not take erectile dysfunction medicine (Viagra, Cialis, Levitra, Stendra, Staxyn, sildenafil, avanafil, tadalafil, vardenafil) while you are taking nitroglycerin. Using erectile dysfunction medicine with nitroglycerin can cause a sudden and serious decrease in blood pressure.
You should not use sublingual nitroglycerin if you have:
severe anemia (low red blood cells);
symptoms of circulation problems or shock (pale skin, cold sweat, fast or irregular heartbeats, sudden weakness or feeling like you might pass out).
To make sure nitroglycerin is safe for you, tell your doctor if you have:
congestive heart failure, or a heart rhythm disorder (especially if you take medicine to treat this condition);
a history of heart attack, stroke, or head injury;
low blood pressure, or if you are dehydrated;
It is not known whether nitroglycerin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.
It is not known whether nitroglycerin passes into breast milk or if it could affect the nursing baby. Tell your doctor if you are breast-feeding.
How should I take nitroglycerin?
Follow all directions on your prescription label. Do not take nitroglycerin in larger or smaller amounts or for longer than recommended. If you use too much nitroglycerin, it might stop working as well in controlling your symptoms.
Nitroglycerin is usually taken at the first sign of chest pain. Try to rest or stay seated when you take nitroglycerin (may cause dizziness or fainting).
You may use nitroglycerin sublingual within 5 to 10 minutes before an activity you think might cause chest pain. Follow your doctor's instructions.
Do not crush, chew, break, or open an extended-release capsule. Swallow it whole.
The sublingual tablet should be placed under your tongue and allowed to dissolve slowly. Do not chew or swallow it. Do not use more than 3 tablets in 15 minutes.
If you use nitroglycerin sublingual spray: At the first sign of an attack, apply the spray directly on or under your tongue. Close your mouth after each spray. Do not inhale the spray. Do not shake the spray before or during use. You may use additional sprays every 5 minutes, but not more than 3 sprays in 15 minutes.
You may need to use 1 or 2 packets of nitroglycerin sublingual powder. Follow your doctor's instructions. Do not use more than 3 packets within 15 minutes.
Seek emergency medical attention if your chest pain gets worse or lasts more than 5 minutes, especially if you have trouble breathing or feel weak, dizzy, or nauseated, or lightheaded.
You may feel a slight burning or stinging in your mouth when you use this medicine. This is not a sign of how well the medicine is working. Do not use more just because you do not feel a burning or stinging.
This medicine can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using nitroglycerin.
If you take nitroglycerin on a regular schedule to prevent angina, do not stop taking it suddenly or you could have a severe attack of angina. Keep this medicine on hand at all times. Get your prescription refilled before you run out of medicine completely.
Store at room temperature away from moisture and heat. Keep the tablets in the original glass container, tightly closed when not in use.
Keep the spray away from open flame or high heat, such as in a car on a hot day. The canister may explode if it gets too hot.
What happens if I miss a dose?
Since nitroglycerin is used when needed, you may not be on a dosing schedule. If you are on a schedule, use the missed dose as soon as you remember. Skip the missed dose if your next dose is less than 2 hours away. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of nitroglycerin can be fatal.
Overdose symptoms may include a severe throbbing headache, confusion, fever, fast or pounding heartbeats, dizziness, vision problems, vomiting, bloody diarrhea, trouble breathing, cold or clammy skin, fainting, and seizures.
What should I avoid while taking nitroglycerin?
nitroglycerin may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert. Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.
Avoid drinking alcohol. Alcohol may increase certain side effects of nitroglycerin (dizziness, drowsiness, feeling light-headed, or fainting).
Nitroglycerin side effects
Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Seek emergency medical attention if you have symptoms of a heart attack, such as:
chest pain or pressure;
pain spreading to your jaw or shoulder; or
nausea, sweating, general ill feeling.
Nitroglycerin can cause severe headaches. These headaches may gradually become less severe as you continue to use nitroglycerin. Do not stop taking this medicine. Ask your doctor before using any headache pain medication.
Call your doctor at once if you have:
severe or throbbing headaches that do not become less severe with continued use of nitroglycerin;
pounding heartbeats or fluttering in your chest;
blurred vision or dry mouth; or
a light-headed feeling, like you might pass out.
Common side effects may include:
mild burning or tingling with the tablet in your mouth;
dizziness, spinning sensation;
flushing (warmth, redness, or tingly feeling);
pale skin, increased sweating; or
feeling weak or dizzy.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
See also: Side effects (in more detail)
What other drugs will affect nitroglycerin?
Many drugs can interact with nitroglycerin. Not all possible interactions are listed here. Tell your doctor about all your medications and any you start or stop using during treatment with nitroglycerin, especially:
a diuretic or "water pill";
medicine to treat depression or mental illness; or
This list is not complete and many other drugs can interact with nitroglycerin. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.
Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Copyright 1996-2018 Cerner Multum, Inc. Version: 13.05.
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