Health Library

Nitroglycerin (By mouth)

Nitroglycerin (nye-troe-GLIS-er-in)

Treats or prevents angina (chest pain). This medicine is a nitrate.

Brand Name(s):

Nitro-Time, Nitrostat

When This Medicine Should Not Be Used:

How to Use This Medicine:

Long Acting Capsule, Tablet, Long Acting Tablet

• Your doctor will tell you how much medicine to use. Do not use more than directed. Sit down before you take this medicine, because it could make you lightheaded.
• Most people use this medicine for only part of the day or as needed.
• Extended-release capsule or extended-release tablet:
  • Take on an empty stomach with a full glass of water.
  • Swallow whole. Do not crush, break, or chew it.
• Buccal tablet:
  • Place it between your gum and upper cheek or upper lip. Let the tablet dissolve slowly in your mouth over several hours. Do not chew, crush, or swallow the tablet or put it under your tongue.
  • Avoid drinking anything hot while the tablet is in your mouth and do not touch the tablet with your tongue.
  • Do not go to sleep with a buccal tablet in your mouth.
• Sublingual tablet:
  • Wet the tablet with saliva and place it under your tongue or inside your cheek. Let the tablet dissolve. Do not chew, crush, or swallow the tablet. Wait 5 minutes. If you still have pain, take a second tablet. Do not take more than 3 tablets in 15 minutes. If you still have pain after you take a total of 3 tablets, this is an emergency. Call 911. Do not drive yourself to the hospital.
  • You may use this medicine 5 to 10 minutes before an activity that can cause angina. This may help prevent the attack.
• Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
• Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Store the sublingual tablets at room temperature in the original glass container, away from heat, moisture, and direct light.

How to Store and Dispose of This Medicine:

• Store the medicine at room temperature in a closed container, away from heat, moisture, and direct light. Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
• Keep all medicine out of the reach of children and never share your medicine with anyone.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Do not use this medicine if you are also using avanafil, riociguat, sildenafil, tadalafil, or vardenafil.
• Some medicines can affect how nitroglycerin works. Tell your doctor if you are using any of the following:
  • Alteplase, aspirin, heparin
  • Blood pressure medicine
  • Diuretic (water pill)
  • Ergot medicine
• Tell your doctor if you are using any medicine that makes your mouth dry, such as medicines that treat depression.
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, anemia, congestive heart failure, enlarged heart, low blood pressure, or a recent heart attack. Tell your doctor if you have a history of a head injury.
• This medicine may make you dizzy or lightheaded. Do not drive or do anything else that could be dangerous until you know how this medicine affects you. These symptoms may be worse if you drink alcohol.
• Medicines that treat chest pain sometimes cause headaches when you first start using it. This is normal. Do not stop using the medicine or change the time you use it to avoid headaches. Ask your doctor if you can take aspirin or acetaminophen to treat the headache.
• Tell any doctor or dentist who treats you that you are using this medicine. This medicine may affect certain medical test results.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Blurred vision, dry mouth
• Increased chest pain, fast or slow heartbeat
• Severe or ongoing dizziness, lightheadedness, or fainting
• Throbbing, severe, or ongoing headache, confusion, low fever, or trouble seeing
• Trouble breathing, cold sweat, blue skin, lips, or nails
• Warmth or redness in your face, neck, arms, or upper chest

If you notice these less serious side effects, talk with your doctor:

• Nausea, vomiting, weakness

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024