AminosalicylatePrescription only
Mesalazine
Tablet, granules, suppository or enema
Quick Summary
Mesalazine reduces inflammation in the bowel lining and helps prevent flares.
Ulcerative colitis
Some Crohn's disease
Medical Uses
Ulcerative colitis: Treating flares and keeping it settled.
Some Crohn's disease: Less commonly.
How it's taken
Swallow tablets whole. Take long term as prescribed.
Your doctor decides the right dose for you and how long to take it.
Your doctor decides the right dose for you. Follow their instructions and the label.
Common Side Effects
Headache
Sometimes.
Tummy pain
Or diarrhoea.
Rash
Rarely.
Interactions
Azathioprine
Monitoring needed.
Critical Warnings
Kidney checks
Regular blood tests.
Unexplained bruising, fever or sore throat
Report straight away.
Sources and further reading
Last updated 21 October 2026. For more detail, see these trusted health organisations.
- Mesalamine: drug information(opens in a new tab) · MedlinePlus, US National Library of Medicine
- Mesalazine: a medicine to treat inflammatory bowel conditions including ulcerative colitis and Crohn's disease(opens in a new tab) · NHS