Nitroglycerin (Rectal)

Rectal nitroglycerin ointment is an effective medication for reducing muscle pressure and to relieve pain due to chronic anal fissures.


Nitroglycerin is part of a medicinal group known as nitrates that help relax muscles around blood vessels. While there are several types of nitroglycerin, the prescription rectal ointment works to relieve pressure and discomfort caused by chronic anal fissures, which are tears in the skin around the rectum. RECTIV, the brand name for the ointment, helps dilate the blood vessels and relax the muscles so the pressure inside the anus reduces. To ensure the ointment is safe for the individual taking it, a doctor should evaluate other medications and medical conditions of each patient.

Conditions treated

  • Chronic anal fissures

Type Of Medicine

  • Nitrate

Side Effects

In addition to the necessary effects of rectal nitroglycerin, some unwanted side effects may occur. While not all of the side effects do occur, some may require medical attention when they do. If you experience severe side effects or side effects continue or reoccur after using nitroglycerin, please contact your physician for additional information.

Common Side Effects

The most common side effect of this medication is a headache. The purpose of nitrates is to open up blood vessels so blood can flow through more easily. When using medication, however, the blood vessels in the head can open as well, causing a headache. In most cases, the headache can be taken care of with a dose of acetaminophen. However, it may reoccur with each use of the ointment. If this happens, talk to your doctor to determine what you can do to stop a headache from forming.

Less Common Side Effects

  • Burning or itchy feeling
  • Numbness, pins and needles feeling
  • Feeling of heat or warmth throughout the body or on one specific area
  • Swelling of the arms, lower legs, feet, hands or face
  • Increased weight
  • Tightness in chest
  • Sweating
  • Trouble breathing
  • Feeling lightheaded, faint or dizzy
  • Weight loss
  • Tingling in extremities

Rare Side Effects

  • Dark urine
  • Rapid heartbeat
  • Fever
  • Blue/Purple-colored fingernails, palms or lips
  • Pale skin
  • Unusually tired or weak
  • Unusually bruising or bleeding

Side Effects With Incidence Not Known

  • Blurred vision
  • Heaviness or tightness in chest
  • Jaw pain
  • Arm pain
  • Back pain
  • Chest discomfort or pain
  • Scaly skin
  • Fainting
  • Lightheadedness when standing or sitting up
  • Trouble swallowing
  • Cracks in skin
  • Sensation that you're spinning
  • Red skin on the upper chest, arms, neck, or face
  • Hives
  • Weakness


One inch of the ointment is approximately 375mg of ointment, which comes to approximately 1.5mg of nitroglycerin. This is the most common dosage; however, some individuals may require a larger or smaller dose. This can greatly depend on the other types of medications they are taking as well as the medical conditions they suffer from.

To use, cover the finger with a glove and apply one inch of ointment to the finger. If your pain allows, insert the finger into the anus up to the first joint on your finger. Move the finger around, applying the ointment to the inside of the anus. If this causes too much discomfort, you can also apply the rectal nitro ointment to the outside of the anus as well. Dispose of the glove or cot immediately and wash your hands thoroughly.

Repeat this treatment every 12 hours for no more than three weeks. If you miss a dose, apply it as soon as possible. If it's already time for the next dose, continue on with your schedule.

Nitroglycerin acts very quickly in the body and should relieve the pressure and pain in your anus. If your pain does not improve, do not attempt to increase your dose on your own or stop using the medication on your own. Talk to your doctor first. He or she may be able to safely increase your dose or recommend another option.

Overdose Symptoms

This ointment contains serious medication. Overusing it could lead to an overdose. It is also very harmful if swallowed. If you believe the ointment has been swallowed, call the poison control center right away. If you are noticing symptoms related to an overdose, call 911 immediately. Some symptoms to look for are:

  • Double vision
  • Trouble breathing
  • Dark urine
  • Cold, clammy skin
  • Blurred vision
  • Loss of vision
  • Flushed skin
  • Trouble seeing colors
  • Change in consciousness
  • Severe, throbbing headache
  • Paralysis
  • Sore throat
  • Slow heartbeat
  • Loss of appetite
  • Halos around lights
  • Night blindness
  • Bleeding or bruising
  • Tunnel vision


Interactions sometimes change the way a medicine works. While some medicines work fine together, others do not. It's important you tell your doctor about any medications you are taking before the prescription rectal nitroglycerin to you. This includes herbal products, vitamins and supplements as well as nonprescription, over-the-counter drugs. Some of these might interact with the ointment and prevent it from functioning correctly.

Drug Interactions

Avoid any drugs related to the treatment of pulmonary hypertension or erectile dysfunction while using this ointment. These include:

  • Cialis
  • Sildenafil
  • Verapamil
  • Viagra
  • Xanax
  • Aspirin (including low strength)
  • Avanafil
  • Riociguat
  • Tadalafil
  • Vardenafil
  • Alteplase
  • Dihydroergotamine
  • Pancuronium
  • Acetylcysteine

In addition, other medicines may interact with your nitro ointment, including medicines that treat anxiety and depression, diuretics (water pills), heparin and certain over-the-counter drugs.

In some cases, the medication won't be able to be taken while using the ointment. However, with some drugs, a lowered dose may be all that is required. Keep in mind that some medications can increase the risk of particular side effects. Always talk to your doctor or pharmacists about what you take, even if you don't begin taking it until after you've been given the ointment prescription.

Food Interactions

While most food won't interfere with the efficiency of rectal nitroglycerin, alcohol can. Do not consume alcohol of any kind while using this medication.

Disease Interactions

Even if you aren't currently taking any medications, if you have a medical condition, it may affect the use of the nitroglycerin. Some medical problems that would affect this medical ointment include:

  • Severe anemia
  • Congestive heart failure
  • Hypotension (blood pressure that is low)
  • Recent heart attack
  • Heart disease
  • Blood vessel disease
  • Increase head pressure due to trauma
  • Hypovolemia (when the amount of blood in the body is dangerously low)

Be sure to let your doctor know if you're being treated for migraine headaches as well. While the medications you take for a migraine may not interfere with the effects of the nitroglycerin, the ointment may aggravate the migraines. If you experience a headache from the rectal nitro on top of a migraine, it may be more than you can stand. In addition, you might not be able to take acetaminophen for a nitro headache if it interacts with the migraine medicine.


Before using this medication, you should talk to your doctor and weigh the pros and cons. In some cases, it makes sense to use the ointment. In other cases, it might not be best for your overall health. Here are just a few things you should consider before taking the medicine.

Your Age

Nitroglycerin for anal fissures is only suitable for adults over the age of 18. Studies have not been performed on pediatric patients. It is not safe or efficient to use this ointment for younger patients.

In addition to being too young, you might also be too old for the medication. Studies have been performed regarding rectal nitroglycerin and the elderly. However, there has not been proof shown that this ointment is effective for this age group. In fact, the results of the studies were just the opposite. They found that geriatric patients were much more likely to experience side effects like:


Before you use this medicine, make sure you tell your pharmacist or doctor if you are allergic to nitrates, nitroglycerin or isosorbide. Be sure to mention any other allergies you might have as well. While they might not seem like they matter, they could. The drug could contain inactive ingredients that can result in allergic reactions.

If you do have an allergic reaction to the medication, such as swelling of the lips, throat, tongue or face, get immediate medical attention.

Breastfeeding and Pregnancy

There aren't any studies currently that show that using the medication while breastfeeding is bad or good. When making the choice, be sure to weigh the potential benefits against the potential risks prior to using the ointment.

In most cases, a doctor will only recommend this drug during pregnancy and breastfeeding when it is really needed. It isn't known whether this medication will harm an unborn baby or whether the drug will pass to the infant through breast milk.


While using this ointment, avoid operating heavy machinery or driving, especially right after you apply the dosage. You might feel dizzy or lightheaded behind the wheel. Instead, wait a while for the side effects of the medication to stop. In addition, make sure you take the time to stand up or sit up slowly to prevent falling from dizziness.

Don't consume alcohol while you use the medicine. When you use alcohol with the ointment, your blood pressure can be affected. This can result in increased dizziness and lightheadedness.

Storing the Ointment

Swallowing this medication or using too much of it can lead to overdose. Keep it out of the reach of any children to prevent accidental, yet dangerous interactions.

When not using the ointment, store it in a closed container. Keep it at room temperature and away from moisture, heat and direct light. Do not put it in the refrigerator or freezer. It should not be frozen.

Tightly close the tube when you finish using it. In most cases, a doctor will recommend you use the medication for only three weeks. After this time, you can dispose of it. If you still have unused medicine after 8 weeks, talk to your physician and ask him where and how you can dispose of it. Do not keep medicine you don't need any longer. Get rid of medicine that is outdated as well.


Rectal nitroglycerin ointment is an effective medication for reducing muscle pressure and to relieve pain due to chronic anal fissures. This medication acts quickly but can cause mild to severe side effects. The most common side effect is a headache, which can be treated with acetaminophen. If other side effects occur, are severe, don't go away or reoccur with each dose, the patient should seek medical attention right away.

Individuals who are allergic to nitrates or have other allergies should talk to their doctor before using this ointment. The ointment is intended for adults and should not be used on children under 18 or the elderly. If you are breastfeeding or pregnant, discuss the pros and cons of using this medication with your doctor.

Do not drink alcohol when using rectal nitroglycerin. This can affect your blood pressure and result in increased dizziness, lightheadedness and fainting. Avoid driving or operating machinery right after applying the dosage.

Certain medical conditions and medications may change the effectiveness of the medication. If you use medicines for erectile dysfunction, blood vessel disorders, low blood pressure, anxiety, depression or a recent heart attack, your doctor may need to lower your dosage to prevent increased side effects. You may not be able to use the medicine if you have anemia, increased pressure in your brain due to trauma or migraine headaches.

In most cases, the dose is a one-inch strip of the medication, approximately 375mg of the ointment and 1.5mg of nitroglycerin. The dose is repeated every 12 hours as needed for pain and may be taken for as long as three weeks. Between uses, store the tube of ointment in a dry place away from light, heat and freezing air.