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Weak immune system and COVID-19

Having a weak immune system may put you at a higher risk of serious illness from COVID-19 (coronavirus).

Many things can cause a weak immune system (immunosuppressed).

These include:

  • cancer treatment
  • some treatments for autoimmune diseases, such as rheumatoid arthritis, lupus, multiple sclerosis (MS) and inflammatory bowel diseases
  • HIV - if you're not on effective treatment
  • having an organ transplant or a bone-marrow transplant
  • if you have a chronic kidney disease and are on dialysis or have an eGFR <30ml/min

COVID-19 vaccination for people with a weak immune system

Non-urgent advice: Contact your GP or doctor urgently if

you have a weak immune system and:

  • you have COVID-19 symptoms, or
  • you test positive for COVID-19

You may be recommended medication to treat COVID-19.

Immunosuppressive treatments and steroids

Being on immunosuppressive treatments is not known to increase your risk of getting COVID-19.

Do not stop or change your medication unless your doctor advises you to. If you stop your medicine without your doctor's advice, you may be more likely to have a flare-up of your condition during this period.

Examples of immunosuppressive medicines are:

  • steroids
  • biologic agents
  • methotrexate
  • azathioprine


If you take steroid tablets every day, you should take extra care to avoid infection. Steroid tablets include prednisolone (Deltacortril).

With steroids, it is always important to take the lowest dose needed to control your condition.

Check with your doctor if you have questions about the dose you are taking. Keep taking your steroids unless your doctor tells you not to. Stopping steroids suddenly can make you very unwell.

If you become unwell due to COVID-19 or another infection, continue to take your steroids. Never start taking steroids unless your doctor tells you to.

Other steroids, such as inhalers, do not usually cause immunosuppression. Continue to take these medicines as you normally would.

Immunosuppressive treatments (non-steroid)

There is currently no evidence that most other immunosuppressive treatments put you at higher risk of severe disease with COVID-19.

This includes biologic agents, methotrexate and azathioprine.

If you have any questions about medicines you are taking, talk to your GP, pharmacist or neurology team.

But, other infections can cause severe illness in people who are on immunosuppressive treatment. You should take care to follow the advice on how to protect yourself from COVID-19.

Attend any planned treatment or blood tests unless you are told not to.

If you test positive for COVID-19

If you get COVID-19, ask your GP or consultant if they recommend any changes to your treatment. Do this before taking your next dose of treatments.

Staying safe if you are at higher risk

Things you can do to protect your health include:

These include:

  • keeping active and looking after your general health - this improves your chance of recovery if you get COVID-19
  • avoiding crowded indoor spaces when possible
  • wearing a face mask, if you would like to
  • washing your hands properly and often
  • moving away if you see someone coughing or sneezing

At home, everyone you live with should keep up to date with their COVID-19 vaccination.

Check that anyone who visits is well when they arrive. Ask them to wash their hands.

Continue to use the healthcare services you need. If you have an appointment with your GP or at a hospital or clinic, it is important to attend.

Page last reviewed: 18 April 2023