Mesalamine (mesalazine)

Pronunciation: me-SAL-a-meen / me-SAL-a-zeen.

Generic name
mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand)
Drug class
Aminosalicylate (5-ASA) -- topical intestinal anti-inflammatory
Form
Delayed-release or extended-release tablet/capsule, granules, suppository, or enema, in a range of strengths depending on brand
Route
Oral or rectal (tablet, capsule, granules, suppository, or enema depending on brand and indication)
Legal status
Prescription-only

Availability and supply rules vary by country

Trade names by country: United States · United Kingdom · Canada · Australia · New Zealand

Australia: Salofalk (5), Pentasa (5) · Full directory

What mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand) is and how it works

Mesalamine (mesalazine) is a prescription-only anti-inflammatory medicine that acts directly in the lining of the bowel. It is used to reduce inflammation in ulcerative colitis, and some formulations are also used to help maintain remission in Crohn's ileocolitis. (1) (2)

Take mesalamine/mesalazine exactly as your prescriber directs, including the specific brand and formulation prescribed -- different products release the medicine in different parts of the bowel and are not interchangeable with each other. Your dose depends on which formulation you use, how active your disease is, and whether you are starting treatment or on maintenance therapy.

Mechanism of action: how mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand) works

Mesalamine/mesalazine (5-aminosalicylic acid) has topical anti-inflammatory action within the intestinal mucosa, reducing prostaglandin and leukotriene synthesis and reactive oxygen species release; different formulations use pH-dependent coatings, sustained-release matrices, or direct rectal delivery to target release to different parts of the colon. (1) (2)

What mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand) is used for

Ulcerative colitis

Used to bring mild to moderately active ulcerative colitis under control (induction) and to help keep it in remission (maintenance), in adults and, for some formulations, children. (1) (2)

Crohn's ileocolitis (maintenance, some formulations)

Some mesalazine brands are also used to help maintain remission of Crohn's disease affecting the ileum and colon (Crohn's ileocolitis). (2)

Before taking mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand)

Do not take / not appropriate for

  • Do not take mesalamine/mesalazine if you are allergic to salicylates, aminosalicylates, or any ingredient in the specific product. (all countries) (1) (2)
  • Some formulations are contraindicated in severe kidney impairment (for example a GFR below 20 mL/min) or severe liver impairment, or in an active stomach/duodenal ulcer or bleeding tendency -- your prescriber will check whether this applies to you and the specific product prescribed. (United Kingdom / Canada label detail, generally applicable) (2) (4)

Tell your clinician about

  • Any kidney or liver problems, past or present.
  • Any history of a reaction that looked like a colitis flare shortly after starting a mesalamine/mesalazine product before (acute intolerance syndrome).
  • Whether you have asthma, since closer monitoring is advised.
  • All other medicines you take, especially azathioprine, 6-mercaptopurine/thioguanine, NSAIDs (like ibuprofen), sulfonylurea diabetes medicines, or warfarin-type anticoagulants.
  • Pregnancy, plans for pregnancy, or breastfeeding.
(1) (2)

How to take mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand)

  • Take exactly the brand, strength, and formulation your prescriber has chosen -- dosing and release mechanism vary between products and are not directly interchangeable.
  • Swallow tablets/capsules whole with food, without splitting or crushing, unless your prescriber or the product information for your specific formulation says otherwise.
  • Use suppositories, enemas, or granules exactly as instructed for that formulation.
  • Drink enough fluids during treatment to help reduce the risk of kidney stones.
(1) (2)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6)

Missed dose

Take a missed dose as soon as you remember unless it is nearly time for the next one, in which case skip the missed dose. Do not take a double dose to make up for one you missed. Contact your prescriber or pharmacist if you are unsure, since the right approach can depend on your specific formulation and dosing schedule.

Overdose

Seek urgent medical attention or contact a poison control service if an overdose is suspected, especially if you develop severe abdominal pain, persistent diarrhoea, or signs of kidney problems. (1)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Headache.

What to notice: Headache.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1) (2)

Abdominal pain, diarrhoea, nausea, indigestion, flatulence, or vomiting.

What to notice: Abdominal pain, diarrhoea, nausea, indigestion, flatulence, or vomiting.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1) (2)

Abnormal liver function test results.

What to notice: Abnormal liver function test results.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Upper respiratory tract infection.

What to notice: Upper respiratory tract infection.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1) (2)

Serious warnings

Mesalamine-induced acute intolerance syndrome — high caution

Symptoms: Worsening cramping, acute abdominal pain, and bloody diarrhoea, sometimes with fever, headache, or rash, typically appearing shortly after starting treatment. This can look very similar to a flare of the underlying disease.

Action: Contact your prescriber promptly if these symptoms develop -- a clinician needs to assess whether this is the underlying disease flaring or a reaction to the medicine, and will decide whether the medicine needs to be stopped. (1) (2)

Kidney problems (including interstitial nephritis) — high caution

Symptoms: Usually no early symptoms; detected through blood and urine tests. Rarely, reduced urination, swelling, or flank pain from kidney stones can occur.

Action: Attend all scheduled kidney function tests before and during treatment. Contact your prescriber promptly if you notice reduced urination or flank pain -- a clinician will decide whether the medicine needs to be adjusted or stopped. (1) (2)

Signs of a serious hypersensitivity reaction affecting the heart, liver, lungs, or blood — emergency

Symptoms: Chest pain, shortness of breath, yellowing of the skin or eyes, unusual bruising or bleeding, unexplained fever, or sore throat.

Action: Seek emergency medical help or contact your prescriber immediately -- a clinician will urgently assess whether the medicine needs to be stopped. (1) (2)

Severe skin reaction — emergency

Symptoms: Widespread rash, blistering or peeling skin, mouth sores, or fever with a rash.

Action: Seek emergency medical help immediately -- these can be signs of a rare but serious skin reaction (such as Stevens-Johnson syndrome, toxic epidermal necrolysis, or DRESS) that needs urgent clinical assessment. (1) (2)

Severe or recurrent headache with visual changes — high caution

Symptoms: Severe or recurrent headache, visual disturbances, or ringing in the ears (tinnitus).

Action: Contact your prescriber promptly for assessment -- this can rarely signal a condition called idiopathic intracranial hypertension. (2)

Interactions

  • NSAIDs (such as ibuprofen or naproxen) can increase the risk of kidney problems when combined with mesalamine/mesalazine. (1) (2)
  • Azathioprine, 6-mercaptopurine, or thioguanine combined with mesalamine/mesalazine can increase the risk of blood cell abnormalities -- regular blood count monitoring is needed. (1) (2)
  • Lactulose may reduce how well some mesalazine formulations work by lowering colonic pH. (2)
  • May increase the blood-sugar-lowering effect of sulfonylurea diabetes medicines. (2)
  • May increase the effect of warfarin-type (coumarin) anticoagulants. (2)
  • Can cause falsely elevated results on certain urinary normetanephrine laboratory tests -- tell any clinician ordering this test that you take mesalamine. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Available data have not shown a reliable link to birth defects, and keeping ulcerative colitis or Crohn's disease under control during pregnancy is generally important. Discuss the benefits and risks of your specific formulation with your prescriber. (1) (2) (3) (4) (5) (6)

Breastfeeding

Mesalamine/mesalazine passes into breast milk in small amounts. Discuss with your prescriber; if breastfeeding, watch the infant for diarrhoea and mention it promptly if it occurs. (1) (2) (3) (4) (5) (6)

Children

Some formulations are approved for children (for example those weighing 24 kg or more in the US label reviewed) -- dosing is weight- and product-specific. (1) (2) (3) (4) (5) (6)

Elderly

No specific dose adjustment based on age alone is described in the sources reviewed, but kidney function is often reduced with age and may be monitored more closely. (1) (2) (3) (4) (5) (6)

Hepatic_impairment

Severe liver impairment is a contraindication for some formulations; mild-to-moderate impairment requires an individual risk/benefit assessment with your prescriber. (1) (2) (3) (4) (5) (6)

Renal_impairment

Severe kidney impairment is a contraindication for some formulations; kidney function should be checked before starting and periodically during treatment for all patients. (1) (2) (3) (4) (5) (6)

Source_ids

US-DAILYMED-MESALAMINE-2026,UK-EMC-MESALAZINE-ASACOL-2026 (1) (2) (3) (4) (5) (6)

Monitoring

Before starting

  • Baseline kidney function (serum creatinine)
  • Baseline liver function where relevant
  • Review of other medicines, especially azathioprine/6-mercaptopurine/thioguanine and NSAIDs

During treatment

  • Periodic kidney function tests (commonly every 3 months in year one, then less often, per UK labelling reviewed).
  • Liver function monitoring if there is pre-existing liver disease.
  • Complete blood counts if unexplained bleeding, bruising, fever, or sore throat occur, especially when combined with azathioprine-type medicines.
  • Watching for symptoms of acute intolerance syndrome, especially in the first weeks of treatment.
(1) (2)

Storage

Store at room temperature, around 15-25C (59-77F), with brief excursions up to 30C generally permitted; keep containers tightly closed. Check the specific storage instructions for your exact formulation (tablet, granules, suppository, or enema), as these can differ.

Professional information

Clinician-facing context only, sourced from the current US FDA prescribing information and UK SmPC reviewed; verify against the current full label for the exact product before prescribing.

United States

Indication: Ulcerative colitis (delayed-release tablet formulation reviewed)

Dose summary: Induction: 2.4-4.8 g once daily with food. Maintenance: 2.4 g once daily. Pediatric (>=24 kg): weight-based dosing for 8 weeks then reduced maintenance dose.

Renal context: Evaluate renal function before and periodically during therapy; avoid concurrent nephrotoxic agents. (1)

United Kingdom

Indication: Ulcerative colitis and Crohn's ileocolitis maintenance (modified-release tablet formulation reviewed)

Dose summary: Mild exacerbation: 2.4 g/day. Moderate exacerbation: 4.8 g/day. Maintenance: up to 2.4 g/day.

Renal context: Contraindicated in severe renal impairment (GFR <20 mL/min); monitor renal function periodically in all patients. (2)

Mechanism of action

Hepatic guidance

Reports of hepatic failure exist in patients with pre-existing liver disease; assess risk/benefit individually and monitor liver function where indicated.

Overdose note

Overdose management is largely supportive; monitor renal function and manage gastrointestinal symptoms as needed. Contact a poison control service for current guidance. (1) (2)

Frequently asked questions

Is mesalamine the same medicine as mesalazine?

Yes -- mesalamine is the US name and mesalazine is the name used in the UK, EU, Canada, Australia, and New Zealand for the same active ingredient (5-aminosalicylic acid, 5-ASA). (1) (2)

Can I switch between different mesalamine/mesalazine brands?

Not without checking with your prescriber or pharmacist first. Different brands release the medicine at different points in the bowel and are not automatically interchangeable, even at what looks like the same total daily dose. (1) (2)

Why might my prescriber order regular kidney function blood tests?

Mesalamine/mesalazine has been linked to rare kidney problems, including interstitial nephritis. Regular blood tests can catch this early, often before you would notice any symptoms. (1) (2)

Is mesalamine/mesalazine available in the US, UK, Europe, Canada, Australia, and New Zealand?

Yes, it is approved and available in all of these regions under various brand names. (1) (2) (3) (4) (5) (6)

What is the mechanism of action of mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand)?

Mesalamine/mesalazine (5-aminosalicylic acid) has topical anti-inflammatory action within the intestinal mucosa, reducing prostaglandin and leukotriene synthesis and reactive oxygen species release; different formulations use pH-dependent coatings, sustained-release matrices, or direct rectal delivery to target release to different parts of the colon. (1) (2)

What is the generic name of Mesalamine (mesalazine)?

The generic name is mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand). (1) (2)

What class of drug is mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand)?

Mesalamine (mesalazine) is classed as: Aminosalicylate (5-ASA) -- topical intestinal anti-inflammatory. (1) (2)

References

  1. MESALAMINE delayed-release tablet (LIALDA-type formulation) -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information · United States · accessed 2026-07-29 · source 1
  2. Asacol 800mg MR Tablets -- Summary of Product Characteristicselectronic medicines compendium (emc), United Kingdom -- AbbVie Ltd · United Kingdom · accessed 2026-07-29 · source 2
  3. Mesalazine -- PSUSA scientific conclusions and list of nationally authorised medicinal products (Asacol, Pentasa, Salofalk, and others)European Medicines Agency (EMA) -- Periodic Safety Update Report Single Assessment (PSUSA) for mesalazine, and nationally authorised EU marketing status · European Union · accessed 2026-07-29 · source 3
  4. MEZAVANT (mesalamine) Product MonographHealth Canada product monograph · Canada · accessed 2026-07-29 · source 4
  5. SALOFALK and PENTASA mesalazine -- ARTG registrationsTherapeutic Goods Administration (TGA), Australia · Australia · accessed 2026-07-29 · source 5
  6. PENTASA New Zealand Data SheetMedsafe (New Zealand regulator) · New Zealand · accessed 2026-07-29 · source 6

Brand names by country

Single-ingredient mesalamine (US); mesalazine (UK, EU, Canada, Australia, New Zealand) names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • Lialda (1)FDA approved currently labeled · 1.2 g · Shire/Takeda
  • Asacol HD / Delzicol (1)FDA approved · 400 mg, 800 mg · Allergan/AbbVie
  • Apriso (1)FDA approved · 0.375 g · Bausch Health
  • Pentasa (1)FDA approved · 250 mg, 500 mg · Takeda

United Kingdom

  • Asacol MR (2)MHRA licensed emc smpc confirmed · 400 mg, 800 mg · AbbVie Ltd
  • Pentasa (2)MHRA licensed · various · Ferring
  • Salofalk (2)MHRA licensed · various · Dr Falk Pharma

Canada

  • Mezavant (4)Health Canada approved confirmed · 1.2 g · Shire Pharma Canada / Takeda
  • Salofalk (4)Health Canada approved confirmed · various · Dr Falk Pharma Canada

Australia

  • Salofalk (5)TGA ARTG registered confirmed · 500 mg, 1 g, 1.5 g, 3 g · Dr Falk Pharma Australia Pty Ltd
  • Pentasa (5)TGA ARTG registered confirmed · 1 g · Ferring Pharmaceuticals Pty Ltd

New Zealand

  • Pentasa (6)Medsafe approved confirmed · 1 g, 2 g, 4 g · Ferring New Zealand
  • Asacol / Asamax (6)Medsafe approved confirmed · 500 mg · varies
View brands in additional countries.

European Union

Asacol / Pentasa / Salofalk (3)