Rectogesic 4 mg/g Rectal Ointment is indicated in adults for relief of pain associated with chronic anal fissure.


What is it used for?

  • Relieving pain due to a tear in the lining of the anus (chronic anal fissure).

How does it work?

  • Rectogesic rectal ointment contains the active ingredient glyceryl trinitrate, which is a type of medicine called a nitrate. It is used to relieve pain associated with anal fissures.
  • An anal fissure is a tear in the lining of the back passage (anus). It is often caused by passing hard stools when you are constipated. The tear is painful and often bleeds when you pass a stool.
  • The tear may also be caused in part by spasm (tightening) of the muscle around the anus (the internal sphincter). Spasm of this muscle also causes pain, because if the muscle around the anus is tight, the blood supply to the anus is reduced.
This can also slow down the healing process.
  • The main treatment for anal fissures involves trying to prevent constipation, because straining to pass the stool and passing large hard stools cause more problems. The tear often heals by itself in a couple of weeks, but may sometimes be ongoing. This is called a chronic anal fissure. Glyceryl trinitrate ointment is used to relieve the pain of a chronic anal fissure and also helps the tear heal.
  • The ointment is applied inside the anus. It works by releasing a chemical called nitric oxide, which is a chemical also made naturally by the body. Nitric oxide relaxes (dilates) blood vessels. It also relaxes the internal sphincter muscle in the anus. This improves the blood supply to the anus, which relieves the pain and helps the fissure to heal.
  • How do I use it?

    • Rectogesic ointment is applied inside the anus using your finger. You can use a finger covering, such as cling film or a finger cot (available from pharmacies) placed on the finger to apply the ointment.
    • Squeeze a strip of ointment 2.5cm long onto the tip of your finger. There is a line on the box containing the ointment that you can use to measure this.
    • Gently insert the finger into the anus up to your first finger joint. Turn your finger to spread the ointment around the inside of the anus.
    • Wash your hands after applying the ointment.
    • You should apply the ointment in this way twice each day (every 12 hours).
    • If you forget a dose don't worry, just apply the ointment as usual when it is next due. Do not apply a double dose to make up for a missed dose.
    • You should keep using the ointment for as long as your doctor has prescribed; this will usually be until the pain has got better (up to a maximum of eight weeks).


    • This medicine is not to be taken by mouth.
    • Although this medicine acts locally when applied to the anus, it is also absorbed into the bloodstream and can therefore have effects on the rest of the body. In particular, it can cause headaches. It may also cause a drop in blood pressure, especially when you move from a lying or sitting position to sitting or standing. The drop in blood pressure can make you feel dizzy or unsteady. To avoid this try changing position slowly. If you do feel dizzy, sit or lie down until the symptoms pass. If affected you should avoid performing potentially hazardous tasks such as driving or operating machinary. Drinking alcohol is likely to enhance any dizziness.
    • The tube of Rectogesic should be disposed of eight weeks after opening it, even if there is still ointment left.

    Not to be used in

    • Children and adolescents under 18 years of age.
    • People who are allergic to nitrates.
    • People using other nitrate medicines or certain medicines for erectile dysfunction (see end of factsheet).
    • People with low blood pressure (hypotension).
    • People who suffer from drops in blood pressure and dizziness when moving from lying or sitting to sitting or standing (postural hypotension).
    • People with a low volume of circulating blood (hypovolaemia), for example due to dehydration or blood loss.
    • People with raised pressure inside the skull, for example due to a head injury or bleeding in the brain (cerebral haemorrhage).
    • People with poor blood flow to the brain.
    • People who suffer from migraines or recurrent headaches.
    • People with narrowing of the main artery leaving the heart (aortic stenosis).
    • People with narrowing of one of the valves in the heart (mitral valve stenosis).
    • Heart disease in which the muscle of the heart grows abnormally (hypertrophic obstructive cardiomyopathy).
    • Inflammation of the sac surrounding the heart, which stops the heart from beating properly (constrictive pericarditis).
    • Fluid in the sac surrounding the heart, which prevents the heart beating properly (pericardial tamponade).
    • Severe anaemia.
    • Closed angle glaucoma.

    This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.

    If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.

    Use with caution in

    • Elderly people.
    • People with severe liver disease.
    • People with severe kidney disease.
    • People taking diuretic medicines.
    • People with heart failure or who have recently had a heart attack.
    • Pregnancy and breastfeeding

    Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

    The safety of this medicine in pregnancy has not been established. The manufacturer states that it should not be used during pregnancy. Seek further medical advice from your doctor.
    It is not known if glyceryl trinitrate passes into breast milk. For this reason, the manufacturer states that the medicine is not recommended for women who are breastfeeding. Seek further medical advice from your doctor.

    Side effects

    Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.

    Very common (affect more than 1 in 10 people)

    • Headache. This can be relieved with painkillers such as paracetamol. If the headaches are unpleasant or not relieved with painkillers, you may need to ask your doctor whether you should stop using the medicine.

    Common (affect between 1 in 10 and 1 in 100 people)

    • Dizziness.
    • Feeling sick.
    • Blurred vision.
    • Tiredness.

    Uncommon (affect between 1 in 100 and 1 in 1000 people)

    • Vomiting.
    • Diarrhoea.
    • Itching.
    • Anal discomfort.
    • Anal burning or itching.
    • Rectal bleeding.
    • Increased heart rate.
    • Chest pain.
    • Low blood pressure.
    • A drop in blood pressure that causes dizziness when getting up from a sitting or lying down position. 
    • Fainting.
    • Allergic skin reactions.

    The side effects listed above may not include all of the side effects reported by the medicine's manufacturer.

    For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

    How can this medicine affect other medicines?

    It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while using this one, to make sure that the combination is safe.

    You should not take any of the following while you are using Rectogesic, as the combination could produce a significant drop in blood pressure, resulting in dizziness, fainting, or even a heart attack:

    • amyl nitrate (also known as poppers)
    • butyl nitrate
    • glyceryl trinitrate (GTN) for angina or heart failure
    • isosorbide mononitrate
    • isosorbide dinitrate
    • avanafil (Spedra)
    • sildenafil (Viagra)
    • tadalafil (Cialis)
    • vardenafil (Levitra).

    As Rectogesic can cause a drop in blood pressure, this effect may be also be enhanced if Rectogesic is used by people who are taking other medicines that lower blood pressure. These combinations could cause dizziness. Other medicines that lower blood pressure include the following:

    • alcohol
    • aldesleukin
    • alprostadil
    • baclofen
    • benzodiazepines, eg temazepam, diazepam
    • certain antipsychotic medicines, eg haloperidol, chlorpromazine, prochlorperazine
    • diuretic medicines, eg furosemide, triamterene, bendroflumethiazide
    • levodopa
    • medicines to treat high blood pressure (antihypertensives), eg beta-blockers, ACE inhibitors, alpha-blockers, diuretics, calcium-channel blockers
    • MAOI antidepressants, eg phenelzine, tranylcypromine, isocarboxazid
    • tricyclic antidepressants, eg amitriptyline, imipramine, clomipramine
    • tizanidine.