What is Nitroglycerin: Uses, Warnings & Interactions

Follow all the prescriber’s directions. Do not change the dose without talking to the healthcare provider.

Nitroglycerin sublingual tablets and spray are taken as needed during chest pain episodes.

• Take a dose as soon as chest pain starts.

• Alternatively, a dose can be taken five to ten minutes before any activity that might cause chest pain.

• If the first dose does not work, take another one five minutes later.

• Take only three doses in 15 minutes.

• Call a prescriber if chest pain persists after three doses.

• Sit down when taking a dose because it might cause dizziness.

Taking nitroglycerin tablets:

• Put the tablet under the tongue or in the pouch between the cheek and gums. Allow it to dissolve completely.

• Do not chew, crush, or swallow the tablet.

• Store nitroglycerin tablets in their original container at room temperature.

Administering nitroglycerin sublingual spray:

• Prime the spray pump before administering the first dose.

• With the pump close to the mouth, spray the medicine onto or under the tongue.

• Close your mouth.

• Do not spit or rinse your mouth for five to 10 minutes.

• Store the spray at room temperature.

Nitroglycerin capsules, topical ointment, and skin patches are used to prevent angina episodes.

• Take doses every day as prescribed.

• It’s important to have 12 hours off every day, or the medicine will lose its effectiveness. Take doses as prescribed at the times prescribed.

Taking nitroglycerin extended-release capsules:

• Swallow the capsule whole with a drink of water. Do not chew, break, or open it.

• Store nitroglycerin capsules at room temperature.

Administering nitroglycerin topical ointment:

• Take the first dose when you get out of bed in the morning.

• Take the second dose six hours later.

• Take no more doses for the rest of the day.

• Use the applicator when measuring out a dose.

• Squeeze the dose onto the applicator.

• Spread the ointment on the chest or other skin area.

• Tape the applicator in place.

• Store nitroglycerin ointment in the original package at room temperature.

Using the nitroglycerin patch:

• Please read the Patient Information sheet for instructions on applying and removing the patch.

• Place the patch on clear, dry skin only.

• Do not place the patch on skin that is injured, damaged, or recently shaved.

• If the patch falls off, replace it with a new patch.

• Leave the patch on for no more than 12 hours.

• Store nitroglycerin patches at room temperature.

Administering nitroglycerin rectal ointment:

• Nitroglycerin rectal ointment only treats anal fissures.

• Apply to the anus only.

• Apply the ointment every 12 hours.

• Measure a dose onto your finger. Make sure the finger is covered with plastic wrap or a disposable surgical glove.

• Use the dosage guide on the carton to measure a line of ointment onto the finger.

• Insert the covered finger into the anus up to the first joint.

• Smear the ointment around the anal wall.

• If inserting a finger is too painful, apply the dose to the area outside the anus.

• Throw away the finger covering and wash your hands.

• Store nitroglycerin rectal ointment in a closed container at room temperature.

• Throw away any unused medicine after eight weeks.

For acute chest pain, take a missed dose when remembered if necessary.

For chronic chest pain or anal fissure, ask the prescriber how to handle a missed dose.

Do not take extra medicine to make up for a missed dose.

This medicine is not right for everyone. 

Do not use any form of nitroglycerin if you have had an allergic reaction to nitroglycerin, nitrates, or nitrites.

Do not use nitroglycerin tablets, spray, or rectal ointment if you have:

• Severe anemia

• Increased pressure in the head

• A very recent heart attack

Tell any healthcare provider or other healthcare provider who treats you that you are using this medicine. 

Nitroglycerin treatment typically requires regular visits to a healthcare provider and tests to monitor therapy and heart health. Keep all appointments with the prescriber.

Tell your healthcare provider if you are pregnant, breastfeeding, or if you have:

• Low blood pressure

• A recent heart attack

• Heart problems

• Blood disorders

• Migraines

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.

Nitroglycerin may cause headaches, especially at the beginning. These should improve over time.

Do not breastfeed when using this medicine.

Excessive use of nitroglycerin may lead to tolerance. Do not increase the dose or take doses more often than prescribed.

Nitroglycerin should never be used with:

• The erectile dysfunction or pulmonary embolism medications sildenafil, tadalafil, vardenafil, or avanafil

• Adempas (riociguat) or Verquvo (vericiguat)

To avoid potentially serious drug interactions, tell the prescriber about all the drugs and supplements regularly used, particularly:

• Other nitrates or nitrites

• Blood pressure medications

• Drugs that make you urinate (diuretics)

• Drugs that treat migraines, called ergots

• Aspirin

Do not drink alcohol while you are using this medicine.

Tell other doctors or healthcare providers who treat you that you are taking nitroglycerin.