Mesalazine tablets and granules

Sounds like 'me-SAL-a-zeen'

Key points about mesalazine tablets and granules

  • Mesalazine is used to treat bowel conditions such as Crohn's disease and ulcerative colitis.
  • Mesalazine is also called Asacol or Pentasa.
  • Find out how to take it safely and the possible side effects.
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Mesalazine is used to treat bowel conditions such as ulcerative colitis and Crohn's disease. It works by reducing inflammation in your gut and may lessen symptoms of pain and diarrhoea. It allows the damaged areas to heal and helps to prevent symptoms from flaring up.

Mesalazine tablets and granules are specially designed to release mesalazine in your gut, to treat inflammation. In Aotearoa New Zealand there are different brands of mesalazine tablets and granules.

  • Asacol tablets (400 mg and 800 mg)
  • Pentasa tablets (500 mg)
  • Pentasa granules 1 gram per sachet.

The different brands of tablets are designed differently. Don't change brands without checking with your doctor or pharmacist. If you're changed to a different brand of tablet, let your doctor know if you notice any changes to your symptoms when you change brands.

Note: Mesalazine is also available as suppositories and enemas which are used to treat inflammation in the lower bowel or rectum. Read more about mesalazine suppositories and enemas. 

May 2024: Your box of Asacol brand of mesalazine 800 mg tablets may look different 


The New Zealand pack of Asacol tablets is
expected to be unavailable until July 2024. The alternative product is from Australia and is the same brand and product but the packaging looks different. Find out more about the Mesalazine 800 mg tablets (Asacol) supply issue.(external link)

  • The dose of mesalazine will be different for different people.
  • Take your dose at the same times each day. If you need to take your tablets in divided doses, space the doses evenly throughout the day.
  • If you forget to take your dose, take it as soon as you remember. But, if it's nearly time for your next dose, take the next dose at the right time. Don't take extra doses to make up for a forgotten dose. If you're not sure what to do, ask your healthcare provider.
  • Always take your mesalazine exactly as your doctor has told you. The pharmacy label will tell you how much mesalazine to take, how often to take it, and any special instructions.
  • Mesalazine will start working straight away but it may take a week or so for your symptoms to improve. It'll take a few months for the symptoms to go away completely, as it takes time for the gut to heal.

  • Don't crush or chew the granules.
  • Place the granules onto your tongue and wash them down with water or juice. 
  • You can take mesalazine granules with or without food.

Don't break, crush or chew the tablets. 

  • Asacol tablets®: Take before food and swallow the tablets whole with a glass of water (200–250 mLs).
  • Pentasa tablets®: Take with or without food. Swallow the tablets whole with a glass of water (200–250 mLs). If you have trouble swallowing the tablets, you can put them in 50 mL of cold water, stir rapidly and drink straight away.

Take your tablets at the same times each day. If you need to take your tablets in divided doses, space the doses evenly throughout the day.

Like all medicines, mesalazine can cause side effects, but not everyone gets them. Often side effects improve as your body gets used to the new medicine. You will need to have blood tests to make sure it is not affecting your blood or kidneys.

Side effects What should I do?
  • Tummy pain
  • Feeling nauseous (sick) or being sick (vomiting)
  • Gas or wind in the tummy or feeling bloated
  • Diarrhoea (runny poo)
  • These are quite common when you first start taking mesalazine, and usually go away with time.
  • Tell your doctor if they bother you.
  • Signs of problems with your liver such as severe tummy pain, yellowing of the eyes and skin, dark urine.
  • Tell your doctor immediately or ring Healthline 0800 611 116.
  • Signs of an allergic reaction such as skin rash, itching, blisters, peeling skin, swelling of the face, lips, mouth or breathing problems
  • Tell your doctor immediately or ring Healthline 0800 611 116.
  • Signs of problems with your blood cells such as bruising or bleeding easily, ongoing sore throat, mouth ulcers, dizziness and feeling tired and fever.
  • Tell your doctor immediately or ring Healthline 0800 611 116.
For more information on side effects, see the Medsafe consumer information leaflets below. 

Read more about medicines and side effects and reporting a reaction you think might be a side effect.

The following links have more information on oral mesalazine.

Mesalazine(external link) NZ Formulary 
Asacol®(external link) Medsafe Consumer Information Sheet, NZ
Asamax 500®(external link) Medsafe Consumer Information Sheet, NZ
Pentasa®(external link) Medsafe Consumer Information Sheet, NZ

Resources

Symptom diary [PDF, 114 KB] Use this diary to track your symptoms throughout the day.
5 questions to ask about your medications(external link) Health Quality and Safety Commission, NZ, 2019 English(external link), te reo Māori(external link)

References

Mesalazine(external link) NZ Formulary
Asacol®(external link) Medsafe, NZ
Asamax 500®(external link)  Medsafe, NZ
Pentasa®(external link) Medsafe, NZ

Brochures

symptom diary 05june19

Symptom diary [PDF, 114 KB]

Use this diary to track your symptoms throughout the day.

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Credits: Sandra Ponen, Pharmacist, Healthify He Puna Waiora. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Maya Patel, MPharm PGDipClinPharm, Auckland

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