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Mesalamine

Brand names: Lialda, Asacol HD, Apriso, Pentasa, Canasa, Rowasa

Mesalamine calms inflammation in the lining of the colon. It treats and prevents flares of ulcerative colitis.

Brand namesLialda, Asacol HD, Apriso, Pentasa, Canasa, Rowasa
Type of medicineAnti-inflammatory for bowel disease (5-ASA)
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

It comes as pills, capsules, suppositories, and enemas.

What it's used for

  • Ulcerative colitis (treating flares and keeping it in remission)

How to take it

  • Take it as prescribed; some forms need food, others don't. Swallow pills whole.
  • Drink plenty of fluids.
  • Keep taking it when you feel well to help prevent flares.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Headache
  • Stomach pain
  • Gas
  • Nausea
Call your provider todayCramping, bloody diarrhea, and fever getting worse soon after starting (rare reaction)
Call your provider todayChest pain or shortness of breath
Call your provider todayPeeing less or side pain (kidney problems or stones)
Call 911A blistering, peeling, or widespread red rash, especially with fever

Warnings

  • Your provider will check kidney function.
  • Tell your provider about allergies to aspirin or salicylates.

Other medicines, foods, and alcohol

  • Azathioprine and mercaptopurine raise the risk of low blood counts.
  • NSAIDs may raise kidney risk.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Usually continued in pregnancy. Talk with your provider.

Missed doses, overdose, and storage

If you miss a dose

Take it as soon as you remember, unless it's almost time for your next dose. Then skip the missed dose. Don't take two doses at once.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.