Mesalamine (Asacol, Denzicol, Pentasa)

There are a number of different brands of mesalamine, some of which work in different ways. This means that your treatment could be affected by switching between some brands. Each time you collect a new supply from your pharmacy, check to see if it is the same brand as before. If it is different, discuss this with your pharmacist who will advise you.

It is important that you keep your regular appointments with your physician so that your progress can be checked. You may require regular blood tests.

Common side-effects include gastrointestinal symptoms and aches and pains. These tend to be minor.

Rarely, mesalamine can cause problems with your blood. You should tell your physician immediately if you have any unexplained bleeding, bruising, red or purple discolorations of the skin, sore throat or a high temperature (fever), or if you feel generally unwell.

Type of medicineAn aminosalicylate
Used forUlcerative colitis and Crohn's ileo-colitis, proctitis
Also calledAsacol®; Apriso®; Canasa®; Delzicol®; Lialda®; Pentasa®; Rowasa®
Available asCapsules, tablets, suppositories, enemas

Ulcerative colitis causes inflammation of the intestine, which leads to problems such as ulceration and bleeding. This causes symptoms such as abdominal pain and diarrhea. Crohn's disease is a condition which causes inflammation of any part of the gastrointestinal system. When the inflammation is in the area where the small intestine joins the large intestine then it is called Crohn's ileo-colitis. Aminosalicylates are a group of medicines commonly used to treat inflammatory bowel diseases such as these.

Mesalamine is one of the most commonly used aminosalicylates. Although it is not clear exactly how mesalamine works, it is thought to act on cells lining the intestine to change the way these cells make and release certain chemicals. These chemicals are thought to be a factor in causing the symptoms of ulcerative colitis. Mesalamine allows the damaged intestine to recover and helps to prevent symptoms from flaring up again.

There are a number of different mesalamine preparations, strengths and brands. The way the manufacturers make each of these brands differs slightly; this allows the different brands to release mesalamine in specific areas of the intestine. You will be prescribed the brand that allows mesalamine to be released in the part of your intestine which requires it most.

Mesalamine can be taken by mouth as capsules or tablets, or it can be given into the back passage as a suppository or enema.

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking mesalamine it is important that your physician knows:

  • If you are pregnant or breast-feeding. (Although mesalamine is unlikely to be harmful to babies, it is still important that you tell your physician if you are expecting or breast-feeding a baby.)
  • If you have any problems with the way your liver works, or if you have any problems with the way your kidneys work.
  • If you have any problems with your breathing.
  • If you have ever had an allergic reaction to a medicine. It is particularly important that you tell your physician if you have had an unusual reaction to aspirin or a salicylate.
  • If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as as herbal and complementary medicines.
  • Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about mesalamine, and it will also provide you with a full list of the side-effects which you could experience.
  • Your dose will depend upon which brand of mesalamine has been prescribed for you. Your physician will tell you how much to take and when to take it, and these directions will also be printed on the label of the pack to remind you about what the physician said to you. Take mesalamine exactly as your physician tells you to.
  • Some mesalamine tablets are specially coated to pass through your stomach before they are absorbed. These must be swallowed whole and not broken, chewed or crushed. Check the label on your pack carefully and follow any advice it gives. Also, do not take any indigestion remedies within two hours of taking your doses (either before or after), as this will interfere with the special coating.
  • Some mesalamine capsules can be opened and the contents sprinkled  on to soft food such as applesauce or yogurt. Pour the contents on to a spoonful of food and swallow without chewing the granules. Check the label on your pack carefully and follow any advice it gives.
  • If you forget to take a dose, take it as soon as you remember, unless it is nearly time for your next dose, in which case leave out the missed dose and take the next dose as normal. Do not take two doses together to make up for a forgotten dose.

How to use mesalamine enema

  1. Mesalamine works best when your bowel is empty.
  2. The enema should be inserted at bedtime so it can work overnight.
  3. Shake the enema and release the seal on the nozzle.
  4. Lie down on one side and draw your top knee up towards your chest. Insert the enema nozzle into your back passage.
  5. Squeeze the bottle gently to completely empty the contents. This will take around 30-40 seconds.
  6. Remove the nozzle from your back passage whilst still squeezing the bottle. Remain where you are for about 5-10 minutes until the urge to pass the enema has eased.
  7. Throw away the empty enema bottle in a plastic bag (these are provided with some brands of enema).
  8. Wash your hands.

How to use mesalamine suppositories

  1. Mesalamine works best when your bowel is empty.
  2. The suppository should be inserted at bedtime so it can work overnight.
  3. Remove the suppository from the packaging.
  4. Using your finger, gently push the suppository into your back passage, pointed end first. (Some people find it helps to squat, or to lie down on one side and draw their knees up towards their chest to do this.)
  5. Push the suppository in as far as possible. You may have the urge to pass the suppository out again but this should ease after a few minutes.
  6. Wash your hands.
  • Each time you collect a new supply from your pharmacy, check to see if it is the same brand as before. If it is different, discuss this with your pharmacist who will advise you.
  • Try to keep your regular appointments with your physician and clinic. This is so your physician can check on your progress. Your physician will want you to have regular blood tests during the treatment.
  • Treatment with mesalamine may be long-term to prevent symptom flare-ups. Continue to take/use it unless you are advised otherwise.
  • Your physician may advise you make some changes to your diet as part of your treatment. This can include a special diet or a nutritional supplement.

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with mesalamine. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your physician or pharmacist if any of the following continue or become troublesome.

Common mesalamine side-effects (these affect less than 1 in 10 people)What can I do if I experience this?
Indigestion, feeling nauseous or vomiting, stomach painStick to simple foods - avoid rich or spicy meals
DiarrheaDrink plenty of water to replace lost fluids
Headache, muscle aches and painsDrink plenty of water and ask your pharmacist to recommend a suitable painkiller. If the headaches continue, speak with your physician

Important: rarely, mesalamine can cause problems with your blood. You should contact your physician immediately if you have any unexplained bleeding, bruising, red or purple discolorations of your skin, an unexplained sore throat or high temperature (fever), or if you feel generally unwell during the treatment.

If you experience any other symptoms which you think may be due to this medicine, speak with your physician or pharmacist.

  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the emergency room of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

If you are having any surgery or dental treatment, tell the person carrying out the treatment which medicines you are taking.

Do not keep out-of-date or unwanted medicines. Ask your pharmacist about ways to dispose of medicines safely in your local area.

If you have any questions about this medicine ask your pharmacist.

Did you find this information useful?

Author:
Mr Michael Stewart
Peer Reviewer:
Dr John Cox
Document ID:
29394 (v1)
Last Checked:
03 May 2017
Next Review:
03 May 2020
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