Key takeaways

  • CellCept (mycophenolate mofetil) is a prescription drug that’s used to help prevent organ rejection after an organ transplant. The most common side effects reported with CellCept include diarrhea and vomiting.
  • CellCept works by lowering your immune system. Because of this, it also increases the risk of developing an infection during treatment. In some cases, infections reported with CellCept have been life threatening and even fatal.
  • Side effects of CellCept are similar for adults and children. But children taking CellCept reported certain side effects more frequently than adults, including: stomach pain, respiratory tract infection, anemia, and high blood pressure.

Like other drugs, CellCept can cause mild to serious side effects. Keep reading to learn more.

For more information about CellCept, including details about its uses, see this in-depth article about the drug.

Some people may experience mild to serious side effects during their CellCept treatment. Examples of CellCept’s commonly reported side effects include:

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Some people may experience mild side effects while using CellCept. Examples of mild side effects that have been reported with CellCept include:

  • stomach problems, including diarrhea, vomiting, nausea, and constipation
  • pain in the back, muscles, or stomach
  • swelling in the lower legs, ankles, or feet
  • headache
  • weakness and fatigue

In most cases, these side effects should be temporary. And some may be easily managed. But if you have any symptoms that are ongoing or bother you, talk with your doctor or pharmacist. And do not stop using CellCept unless your doctor recommends it.

CellCept may cause mild side effects other than the ones listed above. See the drug’s prescribing information for details.

In rare cases, it’s possible to have serious side effects from CellCept. Serious side effects that have been reported with CellCept include:

If you develop serious side effects during your CellCept treatment, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Sharing your experience helps make medication safer for everyone by giving doctors and researchers more information about how the drug works in real life. If you develop a side effect while taking CellCept and want to tell the FDA about it, visit MedWatch or call 800-FDA-1088.

CellCept is used to help prevent organ rejection in children ages 3 months and older. It can be used after a liver, kidney, or heart transplant.

Side effects in children using CellCept are similar to those seen in adults. But in CellCept studies, certain side effects were more common in children than in adults. These include:

To learn more about possible side effects your child may have while using CellCept, talk with their doctor.

Allergic reaction

For some people, CellCept can cause an allergic reaction.

This side effect wasn’t reported in the drug’s clinical trials, but serious allergic reactions (including anaphylaxis) have been reported since CellCept was approved for use.

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should keep taking CellCept.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to CellCept, they may have you switch to a different treatment.

Get answers to some frequently asked questions about CellCept’s side effects.

It’s possible. Certain side effects may start during treatment and continue for an extended time. They may start after you’ve been using the drug for a while or after you end your treatment.

Examples of long-term side effects reported in CellCept studies include:

  • risk of cancer

  • risk of serious infections

  • risk of pregnancy complications, including problems with fetal development (commonly known as birth defects) and pregnancy loss

If you have other questions about possible long-term side effects from CellCept, talk with your doctor.

In some cases, it’s possible.

In CellCept studies, people taking the 500-milligram (mg) tablets had the same side effects as people taking the capsules or liquid suspension (a kind of liquid mixture).

In studies, people who received CellCept through an intravenous (IV) infusion generally had the same side effects as people who took the forms that are swallowed. (An IV infusion is an injection into a vein given over a period of time.) In addition, the IV infusion form can cause infusion reactions, such as blood clots or swollen veins.

To learn more about side effects of the different CellCept forms, talk with your doctor or pharmacist.

CellCept has boxed warnings. A boxed warning is the most serious warning from the Food and Drug Administration (FDA).

Risk of cancer: Taking CellCept can increase your risk of developing certain types of cancers. In clinical trials, lymphoma and melanoma (skin cancer) were the two most commonly reported types of cancer with CellCept.

To reduce your risk of skin cancer during your CellCept treatment, you should limit the time you spend in the sun. When you do spend time outdoors, it’s important to use a broad-spectrum sunscreen with a high sun protection factor (SPF). You should also wear clothing that protects your skin, such as a long-sleeved shirt and a hat.

Risk of serious infection: You have an increased risk of serious infection if you take higher doses of CellCept or take CellCept with other drugs that weaken your immune system. These infections can be bacterial, viral, or fungal. They can lead to serious complications that may result in hospitalization and can even be fatal.

Let your doctor know right away if you have symptoms of an infection. They can order tests to determine whether you have an infection and which kind it is. If your doctor confirms you have an infection, they’ll prescribe medication to treat it. They may also lower your CellCept dosage or have you temporarily stop using the medication until your infection has gone away.

Risk of pregnancy complications: It’s not safe to take CellCept during pregnancy. CellCept increases your risk of pregnancy complications, including problems with fetal development (commonly known as birth defects) and pregnancy loss. The risk of pregnancy loss is highest during the first 3 months of pregnancy.

Due to the risk of complications, doctors will not prescribe CellCept to someone who’s pregnant or planning to become pregnant. If you can become pregnant, your doctor will likely have you take a pregnancy test before you start CellCept treatment. They’ll prescribe this medication only if your test is negative. They’ll also have you take another pregnancy test 8 to 10 days after you start using CellCept and then regularly during your treatment.

Pregnancy registry

Your doctor may also talk with you about enrolling in the Mycophenolate REMS pregnancy registry. (Mycophenolate is the active drug in CellCept.) A pregnancy registry helps researchers and doctors gather information about the safety of certain drugs if they’re taken during pregnancy. To learn more, talk with your doctor, call 800-617-8191, or visit the registry website.

Learn more about some of the side effects CellCept may cause.

Neutropenia

Some people may experience neutropenia during their CellCept treatment. With neutropenia, you have low levels of neutrophils (a kind of white blood cell that helps your body fight infections).

Neutropenia was a side effect seen in CellCept studies, but it wasn’t common. Neutropenia is more likely to happen during the first 6 months of your CellCept treatment, though it can occur at any time while you’re using this medication.

Neutropenia doesn’t cause symptoms, but it increases your risk of infection. Symptoms of infection may vary based on the type of infection you have. But examples of symptoms include:

What might help

Your doctor will likely monitor your blood cell levels, including neutrophils, weekly during your first month of CellCept treatment. They’ll then check them twice per month during the second and third months of treatment. After that, they’ll check your blood cell level once per month for the rest of your first year of treatment.

If you develop neutropenia during your CellCept treatment, your doctor may lower your CellCept dosage or have you temporarily stop using CellCept.

Be sure to let your doctor know immediately if you develop symptoms of infection. They’ll do tests to determine whether you have an infection and if needed, they’ll treat the infection.

Anemia

Using CellCept can cause anemia (low level of red blood cells). Red blood cells help carry oxygen to your organs.

Anemia was a common side effect reported in CellCept studies. Symptoms of anemia can include:

What might help

Your doctor will likely check your red blood cell level regularly during your CellCept treatment. If your level becomes low, they’ll provide treatment to raise it.

Tell your doctor if you have symptoms of anemia during your CellCept treatment. They’ll do blood tests to check your red blood cell level. If your doctor confirms that it’s low, they’ll likely recommend treatment with vitamins or supplements that can help your body make more red blood cells. Examples include:

You can also eat foods rich in these nutrients to reduce your risk of anemia or to help increase your red blood cell level. Examples of these foods include:

  • lentils
  • spinach
  • seafood
  • meat
  • eggs

Before taking CellCept, discuss your health history with your doctor. CellCept may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

  • phenylketonuria
  • stomach problems
  • HGPRT enzyme deficiency
  • previous allergic reaction to CellCept or any of its ingredients, including Polysorbate 80
  • plans to donate blood or sperm
  • alcohol consumption
  • pregnancy or breastfeeding

Like all medications, CellCept may cause some mild or serious side effects. Talking with your doctor can help you learn what to expect from this medication before you start treatment. Your doctor can also recommend ways to help you mange any side effects if they occur.

Examples of questions you may want to ask your doctor include:

  • Can CellCept cause anxiety?
  • Does my risk of anemia depend on the dosage I take?
  • How do the side effects of CellCept compare with those of tacrolimus (Prograf)?
  • Is my risk of depression higher when I first start treatment?
  • Does my age affect my risk of side effects from CellCept?

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.