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Glyceryl trinitrate rectal

Updated 2 Feb 2023 | Anal fissures


Rectal ointment containing glyceryl trinitrate

Drugs List

  • glyceryl trinitrate 0.4% rectal ointment
  • RECTOGESIC 0.4% rectal ointment
  • Therapeutic Indications


    Anal fissure



    Apply 2.5 cm of ointment to the covered finger (approximately 1.5 mg glyceryl trinitrate), which should then be gently inserted in to the anal canal to apply the ointment.

    The dose should be applied every 12 hours. Treatment should be continued until pain abates, up to a maximum of 8 weeks.

    The ointment should be used following conservative treatment failure for acute symptoms of anal fissure.


    (See Dosage; Adult)


    For rectal administration.

    A finger covering, such as cling film or a finger cot may be placed on the finger to be used for application of the ointment.


    Children under 18 years
    Frequent headaches
    Aortic stenosis
    Cardiac tamponade
    Cerebrovascular haemorrhage
    Cerebrovascular insufficiency
    Constrictive pericarditis
    Head trauma
    Hypersensitivity to lanolin
    Hypertrophic obstructive cardiomyopathy
    Mitral stenosis
    Narrow angle glaucoma
    Postural hypotension
    Raised intracranial pressure
    Severe anaemia

    Precautions and Warnings

    Congestive cardiac failure
    Myocardial infarction
    Severe hepatic impairment
    Severe renal impairment

    Advise ability to drive/operate machinery may be affected by side effects
    Contains lanolin
    Contains propylene glycol: may cause irritation
    Monitor patients with cardiac disorders
    May cause postural hypotension especially in elderly
    May interfere with certain laboratory measurements
    Hypotensive effects may be potentiated by alcohol

    The risk/benefit ratio of glyceryl trinitrate has to be established on an individual basis. Re-evaluation of the correct dosing may be required in some patients. Excessive hypotension, especially for prolonged periods of time, must be avoided because of possible deleterious effects on the brain, heart, liver and kidney from poor perfusion and the attendant risk of ischaemia, thrombosis and altered function of these organs. Consequently, patients should be advised to change position slowly when changing from lying or sitting to upright. This advice is particularly important for those patients with low blood volume and under diuretic treatment. Paradoxical bradycardia and increased angina pectoris may accompany glyceryl trinitrate-induced hypotension. The elderly may be more susceptible to the development of postural hypotension, particularly on sudden rising. In the event that glyceryl trinitrate ointment is prescribed to patients with cardiac disorders, careful clinical and haemodynamic monitoring is recommended to avoid the potential hazards of hypotension and tachycardia. Consider discontinuation of glyceryl trinitrate if bleeding associated with haemorrhoids increases. If anal pain persists, differential diagnosis may be required to exclude other causes of the pain.

    Pregnancy and Lactation


    Use glyceryl trinitrate with caution during pregnancy.

    There is limited available data on the use of glyceryl trinitrate in pregnant women. Animal studies are inconclusive with respect to effects of glyceryl trinitrate on pregnancy, embryonal/foetal parturition and postnatal development

    Schaefer (2015) suggests that, at the time of writing, toxic effects on the foetus have not been reported and nitrates may be used during pregnancy for appropriate indications, if considered essential.

    Briggs (2015) suggests that the use of glyceryl trinitrate during pregnancy appears to be risk free. However, the number of women studied is limited, especially with regards to the use of glyceryl trinitrate in the first trimester. At low doses, a temporary decrease in maternal blood pressure may occur, but this does not appear to have an impact on placental perfusion.

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).


    Use glyceryl trinitrate with caution during breastfeeding.

    It is not known whether glyceryl trinitrate is excreted in human milk. Therefore the manufacturer does not recommend the use of glyceryl trinitrate 0.4% rectal ointment in a woman who is breastfeeding due to the potential harmful effects on the infant. Briggs (2015) suggests that the small molecular weight (about 227) indicated that the drug may be expressed in breast milk.

    However, Schaefer (2015) suggests that the short half-lives of nitrates and the usually brief usage argue against a toxic risk for the breastfed infant.

    LactMed suggests the use of glyceryl trinitrate for anal fissures by nursing mothers appears to have no adverse effects on the breastfed infants.

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at

    Side Effects

    Anaphylactoid reaction
    Hypersensitivity reactions
    Irritation with burning (application site)
    Itching at application site
    Orthostatic hypotension
    Pain at application site
    Rebound hypertension
    Rectal bleeding
    Rectal disorders

    Effects on Laboratory Tests

    Glyceryl trinitrate can interfere with the measurement of catecholamines and vanilmandelic acid in urine as it increases the excretion of these products.


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: May 2017

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 3rd edition (2015) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 10th edition (2015) ed. Briggs, G., Freeman, R. Wolters Kluwer Health, Philadelphia.

    Joint Formulary Committee. British National Formulary. 73rd ed. London: BMJ Group and Pharmaceutical Press; 2017.

    Summary of Product Characteristics: Rectogesic 4 mg/g Rectal Ointment. Kyowa Kirin Ltd. Revised May 2016.

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Nitroglycerin. Last revised: 07 September 2013
    Last accessed: 26 April 2017

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