If you have a certain lung condition or are receiving a certain kind of organ transplant, your doctor might suggest that you take Rapamune.

Rapamune is a prescription drug used for:

  • preventing kidney transplant rejection in adults and some children
  • treating a rare lung condition called lymphangioleiomyomatosis (LAM) in adults

The active ingredient in Rapamune is sirolimus. An active ingredient is what makes a drug work.

Rapamune comes in two forms:

  • a liquid solution that you swallow
  • a tablet that you swallow

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

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

These are just a few of the more common side effects reported by people who took Rapamune in studies. These side effects can vary depending on the condition the drug is being used to treat.

More common side effects in people taking Rapamune to prevent kidney transplant rejection include:

* To learn more about this side effect, see the “Side effects explained” section below.

More common side effects in people taking Rapamune for LAM include:

Read on to learn about other possible side effects of Rapamune.

Many side effects of Repatha are mild and don’t require medical attention. Examples of mild side effects that have been reported with Rapamune include:

* To learn more about this side effect, see the “Side effects explained” section below.

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 taking Rapamune unless your doctor recommends it.

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

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Rapamune, visit MedWatch.

Taking Rapamune can cause serious side effects. Serious side effects that have been reported with Rapamune include:

* Rapamune has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effects explained” section below.
† To learn more about this side effect, see the “Side effects explained” section below.
‡ An allergic reaction is possible after using Rapamune. But it’s not clear whether this side effect occurred in studies.

If you develop serious side effects while taking Rapamune, 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.

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

Are there any long-term side effects of Rapamune?

Yes, there are some side effects of Rapamune that may be long term. But many side effects of Rapamune are mild and go away after a short time.

Examples of Rapamune side effects that may become long term include increased cholesterol levels and kidney problems. Some long-term side effects may require treatment.

Other side effects, such as a weakened immune system, can last for as long as you take Rapamune. In some cases, the side effects may continue after you stop treatment.

If you’re concerned about long-term side effects from Rapamune treatment, talk with your doctor or pharmacist. They can tell you more about long-term side effects the drug can cause and suggest ways for you to manage them.

Are there foods that may increase my risk of side effects from Rapamune?

Yes, there are foods that could increase your risk of side effects from Rapamune, specifically grapefruit and grapefruit juice.

Your liver uses an enzyme called CYP3A4 to process certain drugs, including Rapamune. Grapefruit prevents this enzyme from working as well as it should. This can cause Rapamune to build up in your body, which increases your risk of side effects.

Due to this risk, it’s recommended that you do not take Rapamune with grapefruit or grapefruit juice. It’s also recommended that you do not dilute Rapamune liquid solution with grapefruit juice. Instead, only dilute Rapamune using water or orange juice.

If you’re concerned about consuming other foods while taking Rapamune, talk with your doctor or pharmacist.

Can Rapamune cause cancer?

Although rare, it’s possible. Rapamune has a boxed warning for increased risk of certain cancers, as well as infections, due to a weakened immune system. A boxed warning is the most serious warning from the Food and Drug Administration (FDA).

Studies of Rapamune reported a few instances of lymphoma (cancer of the lymph system) and skin cancer occurring.

This side effect happened more often in people taking cyclosporine together with Rapamune. But it’s not clear whether taking cyclosporine with Rapamune increases the risk of developing cancer.

For more about Rapamune’s boxed warning for increased risk of infections and certain cancers due to a weakened immune system, see the “Side effects explained” section below. And if you have questions about your risk of developing certain cancers with Rapamune, talk with your doctor.

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

Increased risk of infections and certain cancers due to a weakened immune system

Rapamune has a boxed warning for increased risk of infections and certain cancers due to a weakened immune system.* Boxed warnings are the most serious warnings from the Food and Drug Administration (FDA).

The immune system helps the body fight infection and disease. Rapamune weakens the immune system, which increases the risk of infections. These infections can be bacterial, viral, or fungal, and in some cases they may be life threatening.

Rapamune can also increase the risk of certain cancers, such as lymphoma (cancer of the lymph system) and skin cancer.

Symptoms of infection include:

Symptoms of the kinds of cancer Rapamune may cause include:

* Rapamune also has a boxed warning for increased risk of serious problems after a lung or liver transplant. For more information, see the “Warnings for Rapamune” section below.

What might help

It’s recommended that only doctors with specialized training in kidney transplants and use of medications that affect immune system response prescribe Rapamune to prevent kidney transplant rejection.

The following tips might help you lower your risk of developing infections during Rapamune treatment:

  • Wash your hands with soap frequently and thoroughly.
  • Avoid large crowds.
  • Get an adequate amount of sleep regularly.
  • Avoid close contact with people who are sick.
  • Include plenty of fruits and vegetables in your diet.

If you have symptoms of infection or an infection that won’t go away, talk with your doctor. They may recommend medication to treat the infection. Your doctor may also have you take antibiotics to prevent infections before you start Rapamune treatment.

Protecting your skin from sunlight, avoiding tanning beds, and maintaining a healthy weight can help reduce your risk of developing cancer.

If you have any of the symptoms of cancer listed above, let your doctor know immediately. They’ll likely do tests to determine if you have cancer and discuss treatment options that are right for you.

If you have concerns about infections or cancer occurring while taking Rapamune, talk with your doctor.

Increased blood levels of cholesterol and triglycerides

Increased blood levels of cholesterol and triglycerides were common side effects reported in studies of Rapamune for preventing kidney transplant rejection. Studies of the drug for treating lymphangioleiomyomatosis reported increased cholesterol levels but not triglyceride levels.

High cholesterol or triglyceride levels can cause heart or blood vessel problems.

You likely won’t have symptoms with this side effect. Your doctor would need to do blood tests to find out if your cholesterol or triglyceride levels have increased.

What might help

While you’re taking Rapamune, your doctor may regularly order blood tests to check your cholesterol and triglyceride levels. If your levels are high, your doctor may prescribe medication to lower your cholesterol or triglycerides. They may also adjust your dosage of Rapamune.

Problems with wound healing

Rapamune may cause wounds to heal more slowly than usual. Or the drug can make it difficult for wounds to heal well.

The following may be symptoms of problems with wound healing:

  • drainage from the wound
  • the wound opening up
  • swelling or warmth around the wound
  • wound healing slowly or not properly

What might help

If you have symptoms of wound healing problems, contact your doctor right away. They can check for signs of infection and prescribe antibiotics if necessary. They can also recommend treatments that may help your wound heal.

Low platelet levels

In studies of Rapamune, low platelet levels were a common side effect. Platelets are cells that help blood clot. Having low platelet levels increases the risk of bleeding or makes it more difficult than usual to stop bleeding.

Symptoms of low platelet levels can include:

What might help

If you have any symptoms of low platelet levels, contact your doctor right away. They’ll order a blood test to check your platelet levels. If your platelet levels are too low, your doctor may prescribe medications or treatments to increase your platelets.

Eating foods that are high in folate and other B vitamins, as well as vitamins D, C, and K, can help maintain healthy platelet levels. Examples of these foods include:

  • dark, leafy greens, such as spinach and Brussels sprouts
  • black-eyed peas
  • eggs
  • fish, such as salmon, clams, or tuna
  • cereals and drinks fortified with folate or vitamins B, C, D, or K

For more information about low platelet levels during Rapamune treatment, talk with your doctor.

Allergic reaction

Like most drugs, Rapamune can cause an allergic reaction in some people. But it’s not clear whether this side effect occurred in studies.

Symptoms can be mild to serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin, usually in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

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. Examples include:

  • an antihistamine you take by mouth, such as Benadryl (diphenhydramine)
  • a product you apply to your skin, such as hydrocortisone cream

If your doctor confirms you’ve had a mild allergic reaction to Rapamune, they’ll decide if you should continue using it.

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 Rapamune, they may have you switch to a different treatment.

Keeping track of side effects

During your Rapamune treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you first start taking new drugs or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were taking when you had the side effect
  • how soon you had the side effect after starting that dose
  • what your symptoms were
  • how it affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

Keeping notes and sharing them with your doctor will help them learn more about how Rapamune affects you. They can then use this information to adjust your treatment plan if needed.

Rapamune has several warnings, which may affect whether the drug is a good treatment for your condition.

Boxed warnings

Rapamune has two boxed warnings, as discussed below. Boxed warnings are the most serious warnings from the Food and Drug Administration (FDA).

Increased risk of infections and certain cancers due to a weakened immune system

Rapamune can weaken your immune system, which increases your risk of developing infections and diseases. It also increases your risk of developing cancer, especially lymphoma (cancer of the lymph system) and skin cancer.

To learn more about this warning, see the “Side effects explained” section above.

Increased risk of serious problems after a lung or liver transplant

In studies, Rapamune increased the risk of serious problems and even death when used after lung or liver transplants. Due to this risk, Rapamune should not be used to prevent organ rejection after liver or lung transplants.

For information about safe and effective treatments that prevent organ rejection for these kinds of transplants, talk with your doctor.

Other warnings

Rapamune may not be right for you if you have certain medical conditions. These are known as drug-condition interactions. Other factors may also affect whether Rapamune is a good treatment option for you.

Talk with your doctor about your health history before starting Rapamune. The list below includes factors to consider.

Allergic reaction. If you’ve had an allergic reaction to Rapamune or any of its ingredients, your doctor will likely not prescribe Rapamune. Ask them what other medications are better options for you.

High blood cholesterol levels. Rapamune can increase blood cholesterol levels. If you already have high cholesterol levels, Rapamune may worsen your condition. Your doctor will check your cholesterol levels regularly while you’re taking Rapamune. If your levels get higher, they may adjust your cholesterol medication if you take any and recommend ways to manage your cholesterol.

Reactivation of viral infections. A weakened immune system increases the risk of reactivating viral infections that are latent (not active and without symptoms). Reactivated infections can lead to serious problems, including decreased kidney function. In some cases, this side effect may be life threatening. Tell your doctor about any infections you may have had. They may monitor you closely during treatment for reactivation of viral infections.

Alcohol and Rapamune

There are no known interactions between Rapamune and alcohol. But alcohol can worsen some of Rapamune’s side effects, such as diarrhea, headache, and nausea.

Also, drinking large amounts of alcohol can weaken your immune system and cause liver problems. Both conditions can increase your risk of side effects from Rapamune.

If you have questions about consuming alcohol during Rapamune treatment, talk with your doctor.

Pregnancy and breastfeeding while taking Rapamune

It is not safe to take Rapamune during pregnancy.

If you can become pregnant, your doctor will have you take a pregnancy test before starting Rapamune. They likely will not prescribe this medication unless your test indicates that you’re not pregnant.

If your pregnancy test is negative, your doctor will recommend that you use an effective method of birth control before starting Rapamune treatment. They’ll also recommend that you use this birth control during treatment and for at least 12 weeks after stopping Rapamune.

It’s not known if Rapamune passes into breast milk. But if it does, it could cause serious side effects in a breastfed child. Talk with your doctor if you’re breastfeeding or planning to do so. They’ll discuss safe ways for you to feed your child while taking Rapamune.

Like with other medications, some people taking Rapamune may have side effects. Talk with your doctor before starting Rapamune treatment. They can answer questions about side effects and how to manage them. Knowing more about this medication may make you feel more comfortable about taking it.

Here are a few examples of questions to ask your doctor:

  • Can Rapamune cause hair loss?
  • Does my risk of having high cholesterol levels depend on the dosage I take?
  • How do the side effects of Rapamune compare with those of Prograf?
  • Does my age affect my risk of side effects from Rapamune?

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.