Immunosuppressants are effective treatments for Crohn’s and Colitis. They can help to get your symptoms under control and keep them under control. For many people, taking an immunosuppressant can improve their quality of life.

Immunosuppressants used to treat Crohn’s and Colitis include:

• Steroids, such as prednisolone, beclometasone, and budesonide
• Azathioprine, mercaptopurine and methotrexate
• Anti-TNFs, such as adalimumab, infliximab, and golimumab
• Other biologics, such as risankizumab, ustekinumab and vedolizumab
• JAK inhibitors, such as filgotinib, tofacitinib, and upadacitinib
• Other targeted treatments, such as ozanimod

5-ASAs (aminosalicylates) are not immunosuppressants.

Immunosuppressants affect the way your immune system works. This means you may be at risk of complications associated with a weakened immune system. This includes infections. You can still fight off infections, but not quite as well as other people.

Not all immunosuppressive medicines affect the immune system in the same way. Some affect the immune system more than others, which may put you at greater risk from infection. Or your immunosuppressant might have a greater risk of certain types of infections. Your risk from infection increases as you get older. It is greater if you are under-nourished or obese, if you have certain other illnesses, or if you are in a flare-up. The risk is also greater if you are taking more than one immunosuppressant.

Some immunosuppressants can also slightly increase your risk of developing some types of cancer, in particular skin cancers. This risk is very small.

You can reduce your general risk of infection through good hygiene.

Try to avoid close contact with people who have a serious infection. If this is not possible, some experts recommend taking extra care with hand washing. You could also consider wearing a mask if the person has a respiratory infection.

Some foods can make you unwell from infections such as listeria or salmonella. You can reduce your risk of this through good food hygiene and sensible food choices.

There is little evidence about taking probiotics whilst on an immunosuppressant, but it is generally considered safe.

Your IBD team will make sure your vaccines are up to date before you start an immunosuppressant. Let them know if you are planning to have any vaccines, or you have had a vaccine recently. They will also check:

• If you have ever had chicken pox or been vaccinated against chickenpox. If not, you may be able to be vaccinated before you start treatment.
• You have HIV or hepatitis (a liver infection caused by a virus). You will usually have a blood test to check for these viruses.
• You have ever had tuberculosis (TB) or you have recently been in close contact with someone who has TB. You will usually have a blood test or a chest X-ray to check for TB.

You may also be eligible for:

• Annual flu vaccine
• COVID-19 vaccine and boosters
• Shingles (Shingrix) vaccine
• Pneumococcal vaccine

These are all ‘non-live’ vaccines and are safe for you to have.

You should not have any ‘live’ vaccines while you are taking an immunosuppressant

In the UK live vaccines include:

• Rotavirus vaccine.
• Measles, mumps, and rubella (MMR) vaccine.
• Nasal flu vaccine used in children: the injected flu vaccine used in adults is not live
• Chickenpox vaccine.
• BCG vaccine against TB.
• Yellow fever vaccine.
• Oral typhoid vaccine: but the injected typhoid vaccine is not live

Before you start an immunosuppressant, think about any vaccines that you might need in the future. For example, if you are planning to travel. You might be able to have these before you start treatment.

Close contacts of people who are immunosuppressed should also be up to date with their vaccines. This reduces the risk of spreading infection. If someone you live with has had a live vaccine, they could pass on the infection for up to 2 weeks after. But this risk is very low. If your child is due to receive the live nasal flu vaccine, you can ask for them to have the non-live vaccine instead.

Plan your trip in advance. If you can, try to plan your trip at least 6 to 8 weeks before you go. If you are travelling for more than 3 months, allow a bit longer if you can. This gives you time to get travel advice, order medicines and arrange any vaccines you might need.

IBD passport has useful advice and information on travelling with Crohn’s or Colitis.

See Travelling with Crohn's or Colitis  for more information on planning your trip.

If you are taking an immunosuppressant, you may be slightly more at risk of skin reactions, and in rare cases skin cancer.

Some immunosuppressants make your skin more sensitive to the sun. Exposure to the sun can cause a severe reaction that looks and feels like sunburn. Exposed skin may develop a rash, redness, swelling, blisters, red bumps, or oozing wounds. If the reaction is severe the skin can become infected. Immunosuppressants that can make your skin more sensitive include azathioprine and methotrexate.

People with a weakened immune system are at increased risk of skin infections.

There is likely to be a small risk of skin infection with procedures such as tattooing, body piercing and cosmetic surgery.

In general, laser hair removal is considered safe.

• If you’re on a medicine that increases your sensitivity to sunlight, test laser treatment on a small area of skin first. Immunosuppressants that increase your sensitivity to sunlight include azathioprine and methotrexate.
• Laser treatment around the mouth can re-activate cold sores
• Stay out of the sun for at least 24 hours after treatment

Animals can carry diseases that could make you unwell. Some animals may be more high risk. This includes:

• Reptiles, poultry, rodents, and exotic pets
• Young or sick animals
• Farm animals or wild animals

If you have a weakened immune system, you can still enjoy interacting with animals.

The kennel cough vaccine for dogs is a modified live vaccine. It contains a weakened form of the bacteria that causes kennel cough. If your dog needs a kennel cough vaccine, it can be a good idea to:

• Stay out of the room when the vaccine is given
• Ask someone else to wipe your dog’s face after it has been vaccinated
• Try not to touch or be close to your dog’s face after it has been vaccinated

There is no agreement as to how long you should avoid your dog after it has had a kennel cough vaccine. The product information for the vaccine says that people who have a weakened immune system should avoid contact with vaccinated dogs for up to 6 weeks after vaccination. But the company that makes the vaccine also says that the vaccine is not likely to represent a major risk. And that the risk would be greater if your dog got kennel cough. You may want to discuss precautions or other options with your vet. You could also discuss concerns with your GP or IBD team.

Swimming in open water, such as lakes, rivers, natural pools, and the sea can help your physical and mental health. But it can increase the risk of infections such as tummy bugs and lung, skin, ear, or eye infections.

Who you contact will depend on your local service. But if your symptoms are severe and you need urgent help then contact NHS 111.

Search our Find an IBD nurse specialist page to find your local specialist service.

We follow strict processes to make sure our information is based on up-to-date evidence and easy to understand.

Please email us at evidence@crohnsandcolitis.org.uk if:

• You have any comments or suggestions for improvements
• You would like more information about the sources of evidence we use
• You would like details of any conflicts of interest

You can also write to us at Crohn’s & Colitis UK, 1 Bishop Square, Hatfield, AL10 9NE, or contact us through our Helpline: 0300 222 5700