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Terms Of Use


Brand Name(s) : Asacol, Asacol MR, Ipcol, Mesren MR, Mezavant XL, Pentasa, Salofalk, Octasa
Side Effects


Mesalazine should be used with caution in: the elderly, patients with kidney or liver problems, active stomach ulcer disease or bleeding disorders, and women who are pregnant or who are breastfeeding.

It should not be used in: children under 2 years of age, patients with severe kidney or liver problems, or in those who have previously had hypersensitivity to any salicylate drugs (e.g. salicylic acid or aspirin) or had a history of problems (sensitivity to) with sulphasalazine.

Also see list of precautions and interactions.


Store tablets below 25°C and protect from direct sunlight. Keep the bottle tightly closed.


What is it used for?

  • Mesalazine is used to treat a number of problems.
  • It is a member of a class of drugs called aminosalicylates, and it is sometimes called 5-aminosalicylic acid.
  • It is used in the treatment of inflammatory bowel (gut) diseases.
  • In general this drug is used to control the symptoms of a type of inflammatory bowel disease called ulcerative colitis, which is a disease of the lower intestine (colon) characterised by open sores (ulcers) with symptoms such as frequent diarrhoea mixed with blood.
  • Benefits of being on this drug include the prevention of the symptoms of ulcerative colitis and remission (absence of active ulcerative colitis), though active ulcerative colitis is likely to reoccur and so another benefit with ongoing maintenance treatment is to prevent active disease from happening again. It is also used to maintain remission of a Crohn's ileo-colitis, a condition in which the small bowel (known as the ileum) and large bowel (the colon) linings become swollen and sore.

Listed below are the typical uses of balsalazide.

  • Treatment of mild-to-moderate ulcerative colitis
  • Maintaining remission of ulcerative colitis (preventing active ulcerative colitis from reocurring) when given as maintenance treatment
  • Maintaining remission of Crohn's ileo-colitis.

On occasion your doctor may prescribe this medicine to treat a condition not on the above list.


How often do I take it?

  • Take tablets orally, every day. Swallow whole with water, and do not break, crush or chew the tablets before swallowing. Sachets of oral granules should be placed on the tongue and washed down with water or orange juice. It is also available as a suppository or enema, which should be taken rectally.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • It may take several months before the full benefit of this drug takes effect.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • No.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.


Only the most common side effects have been listed. If any of these persist or you consider them severe then inform your doctor.

Tell your doctor immediately if you develop any of the following symptoms: unexplained bleeding, bruising, purpura (red spots/rash caused by a local bleeding within the skin), sore throat, fever, or generally feeling unwell as these symptoms may indicate a blood disorder.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking mesalazine, tell your doctor or pharmacist if you are allergic to it; or to other aminosalicylate drugs, or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: severe liver problems or severe kidney problems, or if hypersensitive to any salicylate drugs (e.g. salicylic acid or aspirin).

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: any previous liver or kidney problems, or a history of problems (sensitivity) to sulphasalazine or salicylate drugs (e.g. salicylic acid or aspirin).

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Not known.

Pregnancy and breastfeeding - please ensure you read the detailed information below


The safety of mesalazine has not been established during pregnancy. Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Mesalazine is not safe to take if you are breastfeeding.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur:

  • None known.

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

  • Cytotoxic agents (e.g. azathioprine or mercaptopurine)
  • Non-steroidal anti-inflammatory drugs (NSAIDs) (e.g. paracetamol)
  • Others: methotrexate (used to treat rheumatoid arthritis, Crohn's disease, psoriasis and cancers) and lactulose (used to treat constipation).

This information does not contain all possible interactions. Therefore, before using mesalazine, tell your doctor or pharmacist of all the products you use.


Side effects of an overdose have not been reported.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of ezetimibe or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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