Nitroglycerin

Introduction

Written by Patricia Weiser, PharmD
Medically reviewed by Alex Brewer, PharmD, MBA
Updated on October 6, 2023

Nitroglycerin (nye troe GLI ser in) is a generic medication prescribed for chest pain. It’s also prescribed for other conditions related to the heart and blood vessels. Nitroglycerin belongs to a group of drugs called nitrates or vasodilators.

Specifically, the Food and Drug Administration (FDA) has approved nitroglycerin in adults to:

• treat sudden attacks of chest pain caused by coronary artery disease
• prevent chest pain caused by coronary artery disease
• lower blood pressure before, during, and after surgery
• manage heart failure after a heart attack

These approved uses differ based on the form of nitroglycerin your doctor prescribes.

This article doesn’t provide coupons for all forms of nitroglycerin. To find coupons for other forms of nitroglycerin, see the following pages:

• Nitroglycerin ER, Nitro-Dur, and more
• Nitroglycerin Transdermal, Nitroglycerin, Nitroglycerin Lingual, Minitran
• Nitroglycerin Lingual, Nitroglycerin, Nitroglycerin Transdermal, Minitran

Note: The FDA has not approved nitroglycerin extended-release (ER)* oral capsule. This is because this form of the drug has been available since before the FDA began its drug approval process. If you have questions about this, talk with your doctor or pharmacist. 

* ”Extended release” (ER) means the drug is slowly released into your body over a long period of time.

Side effects of nitroglycerin

Nitroglycerin may cause mild or serious side effects. More common mild side effects of nitroglycerin and its serious side effects are listed below. This article doesn’t include all possible side effects of the drug. Side effects can vary based on your age, overall health, and any other medications you take.

To learn more about nitroglycerin’s side effects, ask your doctor or pharmacist. You can also refer to the prescribing information for nitroglycerin listed in the “Resources” section.

Mild side effects

More common mild side effects reported with some forms of nitroglycerin are listed below. These side effects may differ based on the form of nitroglycerin prescribed. 

This article doesn’t include all possible mild side effects of the drug. To learn more about nitroglycerin’s side effects based on the form, refer to the prescribing information for nitroglycerin listed in the “Resources” section.

With many drugs, mild side effects may go away within a few days or a couple of weeks. If the side effects are bothersome, tell your doctor or pharmacist. They may be able to suggest ways to manage them.

Nitroglycerin sublingual tablet’s and nitroglycerin sublingual spray’s mild side effects include:

• headache
• dizziness
• numbness or tingling sensation
• mild allergic reaction*

* For details about this side effect, see the “Interactions and warnings for nitroglycerin” section.

Serious side effects

Serious side effects of nitroglycerin are listed below. These side effects may differ based on the form of nitroglycerin prescribed. 

This article doesn’t include all possible serious side effects of the drug. To learn more about nitroglycerin’s side effects based on the form, refer to the prescribing information for nitroglycerin listed in the “Resources” section.

With many drugs, serious side effects are possible but not common. If you have serious side effects from this drug, call your doctor right away. If you’re having severe symptoms or a medical emergency, call 911 or a local emergency number. 

In general, nitroglycerin’s serious side effects include:

• severe headache
• very low blood pressure, which may lead to syncope (fainting)
• a sudden increase in blood pressure that may occur when you stop taking nitroglycerin or the drug wears off
• severe allergic reaction*

* For details about this side effect, see the “Interactions and warnings for nitroglycerin” section.

Uses of nitroglycerin

The Food and Drug Administration (FDA) approves prescription drugs such as nitroglycerin for certain conditions. Approved uses for nitroglycerin are described below. These uses differ based on the form of nitroglycerin prescribed.

Use for chest pain

Doctors may prescribe nitroglycerin sublingual tablet and spray* for treating and helping prevent sudden attacks of chest pain caused by coronary artery disease. These forms start working within minutes to help relieve chest pain or prevent it from occurring. Doctors may prescribe intravenous (IV) injection† to treat chest pain, but not to prevent it.

Doctors may prescribe nitroglycerin transdermal patch‡ or oral extended-release (ER)^§ capsule for helping to prevent chest pain caused by coronary artery disease. But these forms do not start working quickly, so they aren’t used to treat or prevent a sudden attack of chest pain.

Nitroglycerin is used for these purposes in adults. It may be prescribed as a long-term or short-term treatment.

With coronary artery disease, you have less blood flow to your heart. When your heart doesn’t get enough blood, your heart muscles don’t have enough oxygen to function properly. This leads to a type of chest pain called angina. 

* These forms are absorbed when placed under your tongue.
† This is an injection given into your vein over time.
‡ This is a patch you place on your body, and the medication is absorbed through your skin.
^§ “Extended release” (ER) means the drug is slowly released into your body over a long period of time. Note: The FDA has not approved nitroglycerin ER oral capsule. This is because this form of the drug has been available since before the FDA began its drug approval process.

Use for other conditions related to the heart and blood vessels

Doctors may prescribe nitroglycerin intravenous (IV) injection* to lower blood pressure before, during, and after surgery. In addition, nitroglycerin IV injection is used to manage heart failure after a heart attack. 

It’s used for these purposes in adults. It’s usually prescribed as a short-term treatment.

* This is an injection given into your vein over time.

Common questions about nitroglycerin

Below you’ll find answers to a few commonly asked questions about nitroglycerin.

What brand names are available for nitroglycerin?

Nitroglycerin is a generic medication. Available brand-name versions include:

• Nitromist, which comes as a spray that you apply on or under your tongue
• Nitro-Dur, which comes as a transdermal film (skin patch) that you place on your body, and the medication is absorbed through your skin
• Nitrostat, which comes as a tablet that’s absorbed when placed under your tongue
• Rectiv, which comes as an ointment you apply inside your anus

Nitroglycerin intravenous (IV) injection* and nitroglycerin extended-release (ER)† oral capsules are not available in brand-name versions.

A generic medication is an identical copy of the active drug in a brand-name medication. (An active drug is the ingredient that makes a medication work.) Generic drugs are believed to be as effective and safe as brand-name drugs. And generic drugs typically cost less than brand-name drugs.

Talk with your doctor or pharmacist to learn more about the differences between generic and brand-name medications for nitroglycerin.

* This is an injection given into your vein over time.
† “Extended release”(ER) means the drug is slowly released into your body over a long period of time. Note: The Food and Drug Administration (FDA) has not approved nitroglycerin ER oral capsule. This is because this form of the drug has been available since before the FDA began its drug approval process.

How does nitroglycerin work? And how long does it take to start working?

Nitroglycerin forms a substance called nitric oxide in your body. Nitric oxide leads to higher levels of another substance called cyclic GMP. This causes certain muscles to relax and blood vessels to widen, which increases blood flow to your heart. This helps your heart pump blood more effectively and can help relieve chest pain.

Certain forms of nitroglycerin start working within a few minutes to relieve chest pain. These include:

• nitroglycerin sublingual tablets, which are absorbed when placed under your tongue
• nitroglycerin spray that you apply on or under your tongue
• nitroglycerin intravenous (IV) injection, which is given into your vein over time

The other forms of the drug take longer to start working, so they aren’t used to relieve a sudden attack of chest pain. These forms include:

• nitroglycerin transdermal patch, which is placed on your body, and the medication is absorbed through your skin
• nitroglycerin extended-release oral capsule, which slowly releases the drug into your body over a long period of time

If you’d like to know more about nitroglycerin’s mechanism of action (how it works), talk with your doctor or pharmacist. 

Interactions and warnings for nitroglycerin

Below, you’ll find information about nitroglycerin’s possible interactions and warnings. 

Interactions of nitroglycerin

Certain things may affect how a drug works. These include getting vaccines, consuming alcohol or certain foods, or taking the drug with other medications. This effect is called a drug interaction. 

Before you start nitroglycerin, ask your doctor to check for possible interactions. Be sure to tell them about any of the following you take or use:

• prescription or over-the-counter drugs
• vitamins, herbs, or supplements

To learn about drug-condition interactions, see the “Warnings for nitroglycerin” section below.

Warnings for nitroglycerin

Some people should not take nitroglycerin, and others should use it cautiously.

Nitroglycerin could cause harm to people with certain health conditions. This effect is called a drug-condition interaction. Other factors can also affect whether nitroglycerin is a safe option for you. These warnings may differ based on the form of nitroglycerin prescribed.

Ask your doctor about specific warnings for nitroglycerin, and be sure to tell your doctor about your:

• current health, including any allergies to medications
• past health conditions or surgeries

Allergic reaction

Nitroglycerin can cause an allergic reaction in some people. Severe allergic reactions are rare but possible.

If you’ve had an allergic reaction to nitroglycerin or any of its ingredients, your doctor will likely not prescribe nitroglycerin. They can tell you about medications that are safer options for you.

A mild allergic reaction may cause the following symptoms:

• skin rash
• itchiness
• flushing (temporary warmth, redness, or deepening of skin color)

A severe allergic reaction may cause the following symptoms:

• swelling under your skin, usually in your hands, feet, eyelids, or lips
• swelling of your mouth, throat, or tongue, which can cause breathing problems 

If you have an allergic reaction to nitroglycerin, call your doctor right away. If you have severe symptoms, call 911 or a local emergency number.

Overdose of nitroglycerin

If you take nitroglycerin by mouth or apply it, you should not take or use more nitroglycerin than your doctor prescribes. For some drugs, doing so may lead to harmful effects or overdose.

If you think you’ve taken or used too much nitroglycerin, call your doctor or pharmacist right away. Or you could call 800-222-1222 to speak with someone at America’s Poison Centers. You can also use its online resource. If you have concerning symptoms, call 911 or a local emergency number immediately. You can also go to the closest emergency room.

Pregnancy or breastfeeding and nitroglycerin

Information about nitroglycerin and pregnancy and breastfeeding is described below.

Nitroglycerin and pregnancy

It’s not known whether nitroglycerin should be taken or used during pregnancy. If you’re planning a pregnancy or can become pregnant, talk with your doctor before starting this medication.

Nitroglycerin and breastfeeding

It’s not known whether nitroglycerin should be taken or used while breastfeeding. If you’re currently breastfeeding or planning to do so, talk with your doctor before starting this medication. 

What to ask your doctor

Let your doctor know if you have questions about nitroglycerin or would like more details about it.

Here’s a list of some possible questions you may want to ask your doctor:

• Do any of my other medications interact with nitroglycerin?
• Is it safe to take expired nitroglycerin sublingual tablets for sudden chest pain?
• What should I do if I have chest pain that doesn’t get better after taking nitroglycerin?

Resources

• Food and Drug Administration. (2023). Orange Book: Approved drug products with therapeutic equivalence evaluations. https://www.accessdata.fda.gov/scripts/cder/ob/index.cfm
• Nitroglycerin injection, solution. (2022). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/578d8159-5ec6-457f-b4a8-9add624d43a8/spl-doc
• Nitroglycerin lingual spray. (2019). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/fadd07b7-189b-4678-ad0f-bf1e4d3d1300/spl-doc
• Nitroglycerin patch. (2020). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/4f85d2e0-2e37-fcd1-276d-5a6466554289/spl-doc
• Nitroglycerin sublingual tablets. (2023). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/8b0c1500-430a-45dd-a316-5da5ccde2514/spl-doc
• Nitroglycerin sustained-release capsules. (2011). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/bd2f4e87-e595-4099-acb9-e36803170f72/spl-doc 

Disclaimer: Optum Perks has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.