Side Effects Of Mesalazine

Like all medicines, mesalazine can cause side effects in some people, but many people have no side effects or only minor ones.

Common side effects of mesalazine

Side effects of mesalazine can vary depending on the type (such as tablets or granules), and the size of your dose. Check the leaflet that comes with your medicine before taking or using.

These common side effects happen in more than 1 in 100 people. There are things you can do to help cope with them:

Speak to a doctor or pharmacist if this advice on how to cope does not help and a side effect is still bothering you or does not go away.

Serious side effects

Serious side effects are rare and happen in less than 1 in 1,000 people

Skin rashes

Severe skin reactions such as Stevens-Johnson syndrome are a rare side effect of mesalazine.

Stevens-Johnson syndrome causes flu-like symptoms, followed by a rash made up of circular patches that are darker in the middle and lighter around the outside (this may not be as obvious on black or brown skin). The affect skin eventually dies and peels off.

This is more likely to happen in the first month of taking mesalazine.

You're more likely to get Stevens-Johnson syndrome if:

• You've had it before after taking mesalazine or certain other medicines
• You have a weakened immune system, for example, from having a condition like HIV or AIDS, or treatment like chemotherapy
• a close family member has had Stevens-Johnson syndrome

To help reduce the chance of you getting a rash that could be confused with Stevens-Johnson syndrome, it's best not to try any new medicines or food during the first 3 months of your treatment.

It's also best to not start taking mesalazine within 2 weeks of a viral infection, vaccination, or rash caused by something else.

Go to A&E now if:

Other serious side effects

Tell your doctor or call 111 straight away if you get:

• unexplained bleeding, an unexplained sore throat or high temperature, bruising, red or purple marks on your skin (these may be less obvious on black or brown skin), or if you feel generally unwell during the treatment - these can be signs of problems with your blood
• a high temperature, chills, a sore throat, ear or sinus pain, a cough, pain when peeing, mouth sores or a wound that will not heal - these can be signs of an infection
• a change in the colour of your pee or the amount you pee, or a sudden pain in the side of your tummy (abdomen)- these can be signs of kidney problems, including kidney stones
• yellowing of the whites of your eyes or your skin (this may be less obvious on black or brown skin), dark pee, stomach pain, high temperature, feeling tired or feeling sick - these can be signs of liver problems
• back or stomach pain, fever, feeling sick or being sick - these can be signs of an inflamed pancreas
• increasingly severe or frequent headaches, changes to your vision, ringing or buzzing in your ears (tinnitus), dizziness, back pain or neck pain - these can be signs of a build-up of pressure around the brain

Call 999 if:

Do not drive yourself to A&E.

The person you speak to at 999 will give you advice about what to do.

Serious allergic reaction

In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to meslazine.

Call 999 now if:

• your lips, mouth, throat or tongue suddenly become swollen
• you're breathing very fast or struggling to breathe (you may become very wheezy or feel like you're choking or gasping for air)
• your throat feels tight or you're struggling to swallow
• your skin, tongue or lips turn blue, grey or pale (if you have black or brown skin, this may be easier to see on the palms of your hands or soles of your feet)
• you suddenly become very confused, drowsy or dizzy
• someone faints and cannot be woken up
• a child is limp, floppy or not responding like they normally do (their head may fall to the side, backwards or forwards, or they may find it difficult to lift their head or focus on your face)

You or the person who's unwell may also have a rash that's swollen, raised, itchy, blistered or peeling.

These can be signs of a serious allergic reaction and may need immediate treatment in hospital.

Other side effects

These are not all the side effects of mesalazine. For a full list, see the leaflet inside your medicines packet.

Reporting side effects

You can report any suspected side effect using the Yellow Card safety scheme.

Visit the Yellow Card website for more information about reporting side effects.

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