Mesalazine (oral)

Sounds like 'me-SAL-a-zeen'

Easy-to-read medicine information about mesalazine– what is it, how to use mesalazine safely and possible side effects.

Type of medicine Also called
  • Belongs to a group of medicines called aminosalicylates
  • Asacol®
  • Asamax 500®
  • Pentasa®

What is mesalazine?

  • Mesalazine is used to treat bowel conditions such as Crohn's disease and ulcerative colitis.
  • It works by reducing inflammation in the gut, and may decrease symptoms such as pain and diarrhoea. It does not cure these conditions. It allows the damaged gut to heal and helps to prevent symptoms from flaring up again.
  • Mesalazine is available in different forms:
    • It can be given by mouth (oral) as tablets or granules.
    • It can be given rectally (through the bottom) as suppositories or enemas.

For more information on mesalazine suppositories and enemas see mesalazine (rectal).

Dose

  • The dose of mesalazine will be different for different people.
  • Mesalazine oral (given by mouth) is available as tablets or granules.
  • Mesalazine tablets are available in different brands which are designed differently. The brands available in New Zealand are:
    • Asacol®
    • Asamax 500®
    • Pentasa®
  • Do not change brands without checking with your doctor or pharmacist. If you are unsure of the brand you are taking, ask your doctor or pharmacist.
  • Sometimes you may need to change to a different brand of mesalazine. Let your doctor know if you notice any changes to your symptoms when you change brands.  
  • 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.

How to take mesalazine

  • Take your mesalazine dose at the same times each day.
  • If you forget to take your dose, take it as soon as you remember that day. But, if it is nearly time for your next dose, just take the next dose at the right time. Do not take double the dose.
  • Mesalazine will start working straight away but it may take a week or so for your symptoms to improve. It will take a few months for the symptoms to go away completely, as it takes time for the gut to heal.

Mesalazine granules

  • Mesalazine granules are in sachets.  
  • You can take mesalazine granules with or without food.
  • To take your dose, cut open the sachet along the dotted line. Empty the granules onto your tongue and wash down with water or juice.
  • Swallow the granules whole without crushing or chewing them. The granules are designed to release mesalazine slowly. Chewing or crushing the granules will cause all the medication to be released at once and will increase your chance of side effects. 

Mesalazine tablets

Asacol tablets®
  • Take Asacol tablets before food.
  • Swallow the tablets whole with a glass of water.
  • Do not break, crush or chew the tablets. They are designed to release mesalazine slowly. Breaking, chewing or crushing the tablets will cause all the medication to be released at once and will increase your chance of side effects. 
Asamax 500 tablets®
  • Take Asamax 500 tablets after food.
  • Swallow the tablets whole with a glass of water.
  • Do not break, crush or chew the tablets. They are designed to release mesalazine slowly. Breaking, chewing or crushing the tablets will cause all the medication to be released at once and will increase your chance of side effects. 
Pentasa tablets®
  • Your can take Pentasa tablets® with or without food.
  • Swallow the tablets whole with a glass of water.
  • Do not break, crush or chew the tablets. They are designed to release the mesalazine slowly. Breaking, chewing or crushing the tablets will cause all the medication to be released at once and will increase your chance of side effects. 
  • If you have trouble swallowing the tablets, you can put them in 50 mL of cold water, stir rapidly and drink straight away.  

Possible side effects

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 troublesome.
  • 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 have problems breathing
  • Tell your doctor immediately or ring HealthLine 0800 611 116

Learn more

Medsafe Consumer Information Sheets:

Asacol® 
Asamax 500® 
Pentasa®

Credits: Sandra Ponen, Pharmacist.