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Updated 2 Feb 2023 | Aspirin


Suppositories containing 150mg aspirin
Suppositories containing 300mg aspirin

Drugs List

  • aspirin 150mg suppository
  • aspirin 300mg suppository
  • Therapeutic Indications


    Relief of mild to moderate pain, including headache, neuralgia, sore throat, migraine

    Relief of pyrexia in colds and influenza

    Management of pain and inflammation in acute and chronic rheumatic disorders, arthritis, sciatica



    150mg suppositories

    Three to four to be used every four hours.

    Not more than 24 suppositories to be used in 24 hours.

    300mg suppositories

    Two to three to be used every four hours.

    Not more than 12 suppositories to be used in 24 hours.


    150mg suppositories

    Three to four to be used every four hours.

    Not more than 24 suppositories to be used in 24 hours.

    300mg suppositories

    Two to three to be used every four hours.

    Not more than 12 suppositories to be used in 24 hours.


    Children over 16 years

    As for adult dose

    Children under 16 years

    Not to be used, unless specifically indicated (e.g. for Kawasaki syndrome)


    Children over 16 years

    As for adult dose

    Children under 16 years

    Not to be used, unless specifically indicated (e.g. for Kawasaki syndrome)

    Patients with Renal Impairment

    Use with caution in renal impairment
    Avoid in severe renal impairment

    Patients with Hepatic Impairment

    Use with caution in hepatic impairment
    Avoid in severe hepatic impairment.


    Active peptic ulceration

    History of peptic ulceration

    Haemophilia, hypoprothrombinaemia or other clotting disorders

    Asthma, urticaria, rhinitis or other evidence of hypersensitivity to aspirin or non steroidal anti-inflammatory drugs.

    Children under 16 years unless specifically indicated (e.g. Kawasaki syndrome)


    Severe renal impairment

    Severe hepatic impairment


    Precautions and Warnings

    Owing to an association with Reye's syndrome, aspirin-containing preparations should not be given to children under 16 years, unless specifically indicated, e.g. for Kawasaki syndrome.

    Asthma - NSAIDs may provoke or exacerbate asthma

    Allergic disorders - NSAIDs may provoke bronchospasm/urticaria in susceptible patients




    Renal impairment

    Hepatic impairment

    Pregnancy, especially third trimester


    Aspirin should be discontinued several days before scheduled surgical procedures.

    Advise patients to contact their doctor if symptoms persist.

    CSM Warnings

    Do not give aspirin to children under 16 unless medically indicated (e.g. for Kawasaki syndrome)

    Any degree of worsening of asthma may be related to the ingestion of NSAIDs, either prescribed or (in the case of ibuprofen and others) purchased over the counter.

    Pregnancy and Lactation


    This medication should be used with extreme caution during the first and second trimester. This product should not be used during the third trimester. Aspirin has been used for many years during pregnancy, however, the safety of aspirin in pregnancy is still under question. Aspirin crosses the placenta and can accumulate in the foetus due to slow elimination by the foetus. Briggs (2008) states that aspirin used near term may prolong gestation and labour, and increase the risk of haemorrhage during delivery. Premature closure of the ductus arteriosus may occur if aspirin is used late in the pregnancy, with the possibility of the associated complication of persistent pulmonary hypertension of the newborn. Therefore, this product is contraindicated during the third trimester and extreme caution is advised if this product is to be used during the first and second trimesters.

    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 14-17 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 at ( ) or if this is unavailable at the backup site ( ).

    Licensed in pregnancy? - No

    Recommended for use in pregnancy? - No

    Known human teratogen? - Unknown

    Crosses placenta? - Aspirin is known to cross the placenta.

    Effects on foetus - There is still a question about the safety of aspirin during the pregnancy, however, use near term is associate with premature closure of the ductus arteriosus, persistent pulmonary hypertension of the newborn, and haemorrhage.

    Pregnancy-specific adverse effects on the mother - Aspirin is associated with prolonged gestation and labour, and haemorrhage.


    The medication is contraindicated while breastfeeding. Aspirin in excreted in breast milk in small amounts, although aspirin clearance from breast milk is slower than that from plasma. High doses of aspirin present a potential risk to the infants platelet function. There is a possible association between aspirin and Reye's syndrome when given to children. Reye's syndrome is a very rare disease, which affects the brain and liver, and can be fatal. Aspirin is associated with significant effects on some nursing infants and should be given to nursing mothers with caution. However, Schaefer (2007) and Lee (2000) both suggest that aspirin should not be used chronically in nursing mothers.

    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

    Drug excreted in breast milk? - Yes.

    Considered suitable or recommended by manufacturer? - No

    UK Drugs in Lactation Advisory Service Classification - Aspirin is classified as - insufficient information relating to breast-feeding available to allow classification as a safe drug.

    Drug substance licensed in infants? - No


    Advise patients to contact their doctor if symptoms persist and to avoid prolonged use without medical supervision.

    Side Effects

    Acute asthma
    Skin reactions
    Swelling of lips and face
    Gastro-intestinal irritation
    Gastro-intestinal ulceration with occult bleeding
    Gastro-intestinal haemorrhage
    Subconjunctival haemorrhage
    Prothrombin time increased
    Blood disorders
    Gastic erosions
    Hypersensitivity reactions
    Local irritation
    Anorectal stenosis


    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 ( ).

    The MHRA have produced 'generic' overdose sections for the top ten drugs for which the NPIS received the greatest number of queries about management of overdose in 2002. This information is attached below:

    Salicylate poisoning is usually associated with plasma concentrations >350 mg/L (2.5 mmol/L). Most adult deaths occur in patients whose concentrations exceed 700 mg/L (95.1 mmol/L). Single doses less than 100 mg/kg are unlikely to cause serious poisoning.

    Signs and Symptoms

    Common features include vomiting, dehydration, tinnitus, vertigo, deafness, sweating, warm extremities with bounding pulses, increased respiratory rate and hyperventilation. Some degree of acid-base disturbance is present in most cases.

    A mixed respiratory alkalosis and metabolic acidosis with normal or high arterial pH (normal or reduced hydrogen ion concentration) is usual in adults and children over the age of four years. In children aged four years or less, a dominant metabolic acidosis with low arterial pH (raised hydrogen ion concentration) is common. Acidosis may increase salicylate transfer across the blood brain barrier.

    Uncommon features include haematemesis, hyperpyrexia, hypoglycaemia, hypokalaemia, thrombocytopaenia, increased INR/PTR, intravascular coagulation, renal failure and non-cardiac pulmonary oedema.

    Central nervous system features including confusion, disorientation, coma and convulsions are less common in adults than in children.


    Give activated charcoal if an adult presents within one hour of ingestion of more than 250 mg/kg. The plasma salicylate concentration should be measured, although the severity of poisoning cannot be determined from this alone and the clinical and biochemical features must be taken into account. Elimination is increased by urinary alkalinisation, which is achieved by the administration of 1.26% sodium bicarbonate. The urine pH should be monitored. Correct metabolic acidosis with intravenous 8.4% sodium bicarbonate (first check serum potassium). Forced diuresis should not be used since it does not enhance salicylate excretion and may cause pulmonary oedema.

    Haemodialysis is the treatment of choice for severe poisoning and should be considered in patients with plasma salicylate concentrations >700 mg/L (5.1 mmol/L), or lower concentrations associated with severe clinical or metabolic features. Patients under ten years or over 70 have increased risk of salicylate toxicity and may require dialysis at an earlier stage.

    Shelf Life and Storage

    Do not store above 25 degrees C

    Reference Sources

    Summary of Product Characteristics: Aspirin Suppositories 150mg and 300mg. Martindale Pharmaceuticals. Last revised May 2006

    British National Formulary, 61st Edition (2011) Pharmaceutical Press, London.

    Martindale: The Complete Drug Reference, 36th edition (2009) ed. Sweetman, S. Pharmaceutical Press, London.

    MHRA 22nd January 2007
    Last accessed: 9th May 2011

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 2nd edition (2007) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 8th edition (2008) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

    Medications and Mother's Milk, 12th edition (2006) Hale, T.W. Hale Publishing, Amarillo, Texas.

    Therapeutics in Pregnancy and Lactation (2000) Lee, A., Inch, S. and Finnigan, D. Radcliffe Medical Press, Abingdon.

    UK Drugs in Lactation Advisory Service.
    Available at:
    Last accessed: March 9, 2009.

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Aspirin Last revised: December 27, 2007.
    Last accessed: March 9, 2009.

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