Immunosuppressants are drugs that prevent your immune system from attacking healthy cells and tissues by mistake. Healthcare providers prescribe immunosuppressants to treat certain autoimmune diseases and prevent organ or stem cell transplant rejection. These medications also increase your risk of infection because your immune system isn’t working as it should.


What are immunosuppressants?

Immunosuppressants are drugs that keep your immune system working as it should. Normally, your immune system is an infection-fighting machine that targets intruders like viruses, bacteria and cancerous cells. But sometimes, your immune system attacks healthy cells and tissues by mistake. Immunosuppressants can slow or stop this response. But immunosuppressants also weaken your immune system, increasing your risk of viral, bacterial and fungal infections.

When do healthcare providers use immunosuppressants?

Healthcare providers prescribe immunosuppressants to treat autoimmune diseases. People who have organ transplants or stem cell transplants (bone marrow transplants) receive immunosuppressants so their immune systems don’t attack the transplanted organ or stem cells.

Autoimmune diseases

If you have an autoimmune disease, it means your immune system stops protecting your body from invaders and starts attacking healthy tissue and cells. Immunosuppressants hold back your immune system, helping prevent further cell damage and inflammation. These drugs minimize symptoms. They can even put some autoimmune diseases into remission (where you have no signs of the disease).

You may need immunosuppressants if you have one of these autoimmune diseases:

Stem cell (bone marrow) transplants

Sometimes, people with blood cancers, blood disorders or bone marrow issues have allogeneic stem cell transplants. These transplants use donated stem cells to replace unhealthy stem cells so your body can start building a new immune system. Healthcare providers treat many conditions with stem cell transplants, including:

This new immune system may view your body as foreign and start attacking your healthy tissues and organs. This is called graft-versus-host disease (GvHD). Immunosuppressants can lower the chances of GvHD, and are used to help prevent and treat GVHD. You may receive different intravenous (IV) or oral immunosuppressants for several days, weeks or months during and after a stem cell transplant. You may need to take immunosuppressants for years until your new immune system settles down.

Organ transplants

If you need an organ transplant, immunosuppressants reduce the risk that your body will reject the transplanted organ. Organ rejection happens because your immune system knows the transplanted organ is new to your body and will treat it like an intruder that should be destroyed. Immunosuppressants protect newly transplanted organs by keeping your immune system’s response managed.


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Procedure Details

How would I take an immunosuppressant?

You may receive immunosuppressants as a pill, liquid, injection or intravenously. Depending on your situation, you may need immunosuppressants for several months up to a year, or longer. For example, people with autoimmune disease may take immunosuppressants indefinitely. People with organ or stem cell transplants take immunosuppressants long term, according to the advice of their healthcare provider.

What are the most common immunosuppressants?

Corticosteroids, such as prednisone, are among the most common immunosuppressants that healthcare providers prescribe. But there are many types of immunosuppressants. Your provider will select a medicine (or a combination of immunosuppressants) based on your specific condition and symptoms. Types of immunosuppressants include:

  • Biologics, like adalimumab (Humira®) and infliximab (Remicade®). Biologics are lab-made drugs that reduce your immune system’s response to intruders.
  • Calcineurin inhibitors, like tacrolimus (Envarsus XR® or Protopic®) and cyclosporine (Gengraf®, Neoral® or Sandimmune®). Calcineurin inhibitors work by blocking an enzyme that stimulates T-cells. T-cells are white blood cells that fight infection.
  • Inosine monophosphate dehydrogenase (IMDH) inhibitors, like mycophenolate mofetil (CellCept®), that affect cell growth.
  • Janus kinase inhibitors, like (Xeljanz®). These drugs reduce inflammation by limiting the activity of certain enzymes (Janus kinases). They’re a type of immunomodulator.
  • Mechanistic target of rapamycin (mTOR) inhibitors,such as sirolimus (Rapamune®). mTOR inhibitors keep cells from growing and multiplying.
  • Monoclonal antibodies,likebasiliximab (Simulect®), that stimulate your immune system to prevent organ transplant rejection.

Risks / Benefits

What are immunosuppressants’ potential benefits?

When your immune system attacks your body, immunosuppressants keep it managed. Immunosuppressants treat some autoimmune disorders. If you have a donated organ or stem cells, immunosuppressants help prevent your body from rejecting your new organ or stem cells.


What are immunosuppressant side effects?

Immunosuppressants are powerful drugs that can cause many side effects:

What are the risks or complications of taking immunosuppressants?

Immunosuppressants can successfully treat some autoimmune diseases or help reduce the risk that your body will reject transplanted organs or stem cells. But there are potential risks or complications.

Missing doses

It’s very important that you take immunosuppressants exactly as prescribed. If you have an autoimmune disorder, skipping a dose may cause your condition to flare up or suddenly get worse. If you’re living with donor organs or stem cells, missing doses increases the risk your body will reject them.

Increased risk of infection

Your immune system protects you from intruders like bacteria, viruses or cancer. If you’re taking immunosuppressants, it means your immune system won’t work as well as it should to get rid of harmful invaders. Your provider may call this being immunocompromised. That increases your risk of infections that may be life-threatening, such as:


Recovery and Outlook

Is there anything I can do to make this treatment easier on me?

If you’re taking immunosuppressants, you’re putting a deliberate, but necessary, dent in your body’s ability to protect you from infection. Here are some things you can do to stay healthy while you’re receiving immunosuppressants:

  • Wash your hands.
  • Talk to your healthcare provider about what vaccines you need.
  • Boost your immune system with nutrient-rich food like fruits, vegetables, grains, proteins and dairy.
  • Get enough rest. A good night’s sleep can support your immune system.

When To Call the Doctor

When should I call my healthcare provider?

Your provider will explain what symptoms may be signs your immunosuppressant isn’t working as well as expected. They’ll monitor your overall health while you’re taking immunosuppressants. They’ll do frequent blood tests to ensure the immunosuppressant is working and to watch for side effects.

Additional Common Questions

Do immunosuppressants affect pregnancy?

Anyone who takes immunosuppressants should talk to their healthcare providers before conceiving. Some immunosuppressants can cause birth defects. Some medicines may be harmful to take during pregnancy or while breastfeeding. You may need to switch to a different medicine.

A note from Cleveland Clinic

Immunosuppressants offer lifesaving benefits for many people. But suppressing your immune system can lead to side effects and increase your risk of health complications like infections. In some cases, those infections could be life-threatening. Your healthcare provider will carefully check on your condition and check for medication side effects. They may change medicines or dosage amounts, so you get effective treatment that causes the fewest side effects and complications. Let your provider know if your side effects are more significant than expected.

Medically Reviewed

Last reviewed on 08/01/2023.

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