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Nitroglycerin (Into the rectum)

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

Treats pain caused by anal fissures (tear in the skin around the opening for bowel movements). This medicine is a nitrate.

Brand Name(s):


There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

You should not use this medicine if you have had an allergic reaction to nitroglycerin or similar medicines, such as isosorbide (Isordil®, Monoket®, or Sorbitrate®). You should not use this medicine if you have severe anemia or increased pressure in the head from an injury or bleeding. Do not use this medicine if you are also using medicine for erectile dysfunction such as sildenafil, tadalafil, vardenafil, Cialis®, Levitra®, or Viagra®.

How to Use This Medicine:


  • Your doctor will tell you how much medicine to use. Do not use more than directed.
  • This medicine is for rectal use only. Do not get it in your eyes, nose, mouth, or vagina. If it does get in these areas, rinse it off right away.
  • To apply the ointment:
    • Wash your hands, then cover your finger with a plastic wrap, disposable surgical glove, or finger cot.
    • Lay the covered finger next to the dosing line on the side of the medicine box. The tip of your finger should be at one end of the dosing line.
    • Squeeze the ointment onto your finger. The amount of medicine should be the same length as the dosing line.
    • Gently insert your finger with the ointment into the anal canal. Do not push your finger past the first finger joint.
    • Carefully apply the ointment around the inner sides of the anal canal.
    • If you have too much pain in the anal canal, apply the ointment directly to the skin on the outside.
    • Throw the finger covering in the garbage and wash your hands.
  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.

If a dose is missed:

  • Apply a dose as soon as you can. If it is almost time for your next dose, wait until then and apply a regular dose. Do not apply extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine:

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep the tube tightly closed after you use the medicine. Throw away any unused medicine 8 weeks after opening the tube for the first time.
  • Ask your pharmacist or doctor how to dispose of the medicine container and any leftover or expired medicine.
  • Keep all medicine out of the reach of children. 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.

  • Make sure your doctor knows if you are also using alteplase (Activase®), aspirin, heparin, reteplase (Retavase®), tenecteplase (TNKase®), ergot medicines (such as dihydroergotamine, ergotamine, Ergomar®, or Migranal®), or a heart or blood pressure medicine (such as atenolol, diltiazem, metoprolol, nifedipine, propranolol, verapamil, Cardizem®, Lotrel®, Norvasc®, Procardia®, Toprol®, or Verelan®).
  • Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

  • Make sure your doctor knows if you are pregnant or breastfeeding, or if you have heart or blood vessel disease, congestive heart failure, low blood pressure, low blood volume, or have had a recent heart attack.
  • This medicine may cause headaches. The headaches are a sign that the medicine is working. Do not stop using the medicine or change how you use it to avoid the headaches.
  • This medicine may make you dizzy or lightheaded. Avoid driving, using machines, or doing anything else that could be dangerous if you are dizzy. You may feel lightheaded when you get up quickly from a lying or sitting position. Getting up slowly will help.
  • Do not use this medicine to treat a skin problem your doctor has not examined.
  • Call your doctor if your symptoms do not improve or if they get worse.
  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments.

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
  • Severe or ongoing dizziness, lightheadedness, or fainting.
  • Throbbing, severe, or ongoing headache.

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

  • Rash or red, swollen skin.
  • Warmth or redness in your face, neck, arms, or upper chest.

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: 5/1/2020

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