Zortress

Introduction

Written by Ashley Wong, PharmD
Medically reviewed by Victor Nguyen, PharmD, MBA 
Updated on November 22, 2023

Everolimus is a generic medication prescribed for certain types of cancers, tumors, or seizure disorders in adults and some children. It’s also prescribed to prevent organ rejection after kidney or liver transplants. Everolimus belongs to a group of drugs called kinase inhibitors.

The Food and Drug Administration (FDA) has approved everolimus for the following conditions:

• specific types of breast cancer
• tumors in the pancreas, stomach, or lungs
• kidney cancer
• noncancerous kidney or brain tumors related to tuberous sclerosis (TS)
• focal onset seizures related to TS
• prevention of organ rejection after kidney or liver transplants

These approved uses differ based on the form of everolimus your doctor prescribes.

Boxed warnings

Certain strengths of everolimus oral tablet have boxed warnings, which are the most serious warnings from the FDA. These include:

• risk of cancer
• risk of serious infections
• risk of kidney blood clots
• risk of kidney damage if taken with high doses of cyclosporine
• risk of death if used after a heart transplant

For details, see the “Interactions and warnings for everolimus” section.

Side effects of everolimus

Everolimus may cause mild or serious side effects. More common mild side effects of everolimus and its serious side effects are listed below. This article doesn’t include all possible side effects of the drug. Side effects can vary based on your age, overall health, and any other medications you take.

To learn more about everolimus’ side effects, ask your doctor or pharmacist. You can also refer to the prescribing information for everolimus listed in the “Resources” section.

Mild side effects

More common mild side effects reported with some forms of everolimus are listed below. These side effects may differ based on the form of everolimus you take.

This article doesn’t include all possible mild side effects of the drug. To learn more about everolimus’ side effects based on the form, refer to the prescribing information for everolimus listed in the “Resources” section.

With many drugs, mild side effects may go away within a few days or a couple of weeks. If the side effects are bothersome, tell your doctor or pharmacist. They may be able to suggest ways to manage them.

Everolimus oral tablet’s mild side effects include:

• canker sores
• diarrhea
• stomach pain
• fatigue
• mild allergic reaction*

Everolimus tablet for oral suspension’s mild side effects include:

• canker sores
• respiratory tract infection
• fever
• vomiting
• mild allergic reaction*

* For details about this side effect, see the “Interactions and warnings for everolimus” section.

Serious side effects

Serious side effects of everolimus are listed below. These side effects may differ based on the form of everolimus you take.

This article doesn’t include all possible serious side effects of the drug. To learn more about everolimus’ side effects based on the form, refer to the prescribing information for everolimus listed in the “Resources” section.

With many drugs, serious side effects are possible but not common. If you have serious side effects from this drug, call your doctor right away. If you’re having severe symptoms or a medical emergency, call 911 or a local emergency number.

In general, everolimus’ serious side effects include: 

• pneumonitis that’s not caused by an infection
• serious infections, including pneumonia
• giant hives
• kidney failure
• slower wound healing
• severe allergic reaction*

* For details about this side effect, see the “Interactions and warnings for everolimus” section.

Common questions about everolimus

Below you’ll find answers to a few commonly asked questions about everolimus.

What brand names are available for everolimus?

Everolimus is available in two forms: an oral tablet and a liquid suspension. (With a liquid suspension, you dissolve a tablet in water and then drink the liquid.)

The brand-name versions of everolimus oral tablet are Afinitor and Zortress. Afinitor and Zortress are available in different strengths. Afinitor is available in 2.5 milligrams (mg), 5 mg, 7.5 mg, and 10 mg tablets. Zortress is available in 0.25 mg, 0.5 mg, 0.75 mg, and 1 mg tablets. The brand-name version of everolimus liquid suspension is Afinitor Disperz.

A generic medication is an identical copy of the active drug in a brand-name medication. (An active drug is the ingredient that makes a medication work.) Generic drugs are believed to be as effective and safe as brand-name drugs. And generic drugs typically cost less compared to brand-name drugs.

If you have more questions about this, talk with your doctor or pharmacist.

How does everolimus work? And how long does it take to start working?

Everolimus works by blocking a protein called mTOR that helps cells grow and spread. mTOR is more prominent in cancer cells. By blocking this protein, everolimus decreases the blood supply to cancer and tumor cells, which stops their growth. For seizures, blocking mTOR lowers the frequency of seizures. For prevention of transplant rejection, everolimus works by blocking the activity of certain parts of your immune system. Your immune system is programmed to attack any foreign materials. Blocking certain parts helps ensure that your immune system doesn’t attack the transplanted organ.

Everolimus starts to work as soon as you start the medication. But it can take time before you notice its effects.

If you’d like to know more about this, talk with your doctor or pharmacist.

Interactions and warnings for everolimus

Below, you’ll find information about everolimus’ possible interactions and warnings.

Interactions of everolimus

Certain things may affect how a drug works. These include getting vaccines, consuming alcohol or certain foods, or taking the drug with other medications. This effect is called a drug interaction.

Before you take everolimus, ask your doctor to check for possible interactions. Be sure to tell them about any of the following you take or use:

• prescription or over-the-counter drugs 
• vitamins, herbs, or supplements

To learn about drug-condition interactions, see the “Warnings for everolimus” section below.

Warnings for everolimus

Some people should not take everolimus, and others should take it cautiously.

Boxed warnings

Lower strengths of everolimus oral tablet (0.25 mg, 0.5 mg, 0.75 mg, and 1 mg tablets) have boxed warnings about certain risks. Boxed warnings are the most serious warnings from the Food and Drug Administration (FDA).

To learn more about these warnings, read below. You can also talk with your doctor or pharmacist.

Risk of cancer. Taking medications that weaken the immune system, such as everolimus, can increase the risk of developing cancer. This side effect was commonly reported in studies of everolimus. These cancers include lymphomas and skin cancers. Due to this risk, it’s important that you use sunscreen and wear sun protective clothing when you’re outside or exposed to ultraviolet light.

Risk of serious infections. Taking drugs that affect your immune system, including everolimus, may raise your risk of serious and life threatening infections. This side effect was commonly reported in studies of everolimus. Symptoms may include fever, chills, or low energy levels. To lower this risk, your doctor may prescribe antibiotics to prevent certain infections.

Risk of kidney blood clots. Everolimus can increase your risk of forming blood clots in the arteries or veins supplying the kidneys. This can cause your transplanted kidney to lose function. This side effect was rarely reported in studies of everolimus. But due to this risk, your doctor will likely order tests to monitor your kidney for blood clots.

Risk of kidney damage if taken with high doses of cyclosporine. Doctors typically prescribe multiple medications to prevent organ rejection after a transplant. Examples of other drugs used for this purpose include cyclosporine, tacrolimus, and mycophenolate mofetil. Taking everolimus with certain doses of cyclosporine can raise the risk of kidney damage. This side effect was reported in studies of everolimus. Symptoms of kidney damage may include urinating less frequently, swelling, confusion, and shortness of breath. Due to this risk, doctors will likely prescribe low dosages of cyclosporine if you’re taking it in combination with everolimus. They may also order blood tests to ensure both drugs reach safe levels in your body.

Risk of death if used after heart transplant. In studies, participants who had a heart transplant and took everolimus had a higher risk of death compared to those who took other drugs. Due to this risk, everolimus should not be taken by people who had a heart transplant.

Other warnings

Everolimus could cause harm to people with certain health conditions. This effect is called a drug-condition interaction. Other factors can also affect whether everolimus is a safe option for you. These warnings may differ based on the form of everolimus you take.

Ask your doctor about specific warnings for everolimus, and be sure to tell your doctor about your:

• current health, including any allergies to medications
• past health conditions or surgeries

Allergic reaction

Everolimus can cause an allergic reaction in some people. Severe allergic reactions are rare but possible.

If you’ve had an allergic reaction to everolimus or any of its ingredients, your doctor will likely not prescribe everolimus. They can tell you about medications that are safer options for you.

A mild allergic reaction may cause the following symptoms:

• skin rash
• itchiness
• flushing (temporary warmth, redness, or deepening of skin color)

A severe allergic reaction may cause the following symptoms:

• swelling under your skin, usually in your hands, feet, eyelids, or lips
• swelling of your mouth, throat, or tongue, which can cause breathing problems

If you have an allergic reaction to everolimus, call your doctor right away. If you have severe symptoms, call 911 or a local emergency number.

Overdose of everolimus

You should not take more everolimus than your doctor prescribes. For some drugs, doing so may lead to harmful effects or overdose.

If you think you’ve taken too much everolimus, call your doctor or pharmacist right away. Or you could call 800-222-1222 to speak with someone at America’s Poison Centers. You can also use its online resource. If you have concerning symptoms, call 911 or a local emergency number immediately. You can also go to the closest emergency room.

Pregnancy or breastfeeding and everolimus

Information about everolimus and pregnancy and breastfeeding is described below.

Everolimus and pregnancy

Everolimus should not be taken during pregnancy. If you’re planning a pregnancy or can become pregnant, talk with your doctor before taking this medication. Your doctor may suggest birth control options to use during treatment with everolimus.

Everolimus and breastfeeding

Everolimus should not be taken while breastfeeding. If you’re currently breastfeeding or planning to do so, talk with your doctor before taking this medication. Your doctor may recommend other ways to feed your child during treatment with everolimus.

Uses of everolimus

The Food and Drug Administration (FDA) approves prescription drugs such as everolimus for certain conditions. Approved uses for everolimus are described below. These uses differ based on the form of everolimus prescribed.

Use for certain cancers and tumors

Doctors may prescribe everolimus oral tablet and liquid suspension for certain types of cancers and tumors. These include:

• hormone receptor-positive, HER-2 negative breast cancer
• advanced renal cell carcinoma (RCC), which is a type of kidney cancer
• neuroendocrine tumors causing pancreatic cancer, gastrointestinal cancer, or lung cancer
• noncancerous kidney or brain tumors related to tuberous sclerosis (TS)

Everolimus is used for these conditions in adults. For the treatment of noncancerous brain tumors, everolimus can also be used in children ages 1 year and older. It’s usually prescribed as a long-term treatment.

Cancer and noncancerous tumors occur when abnormal cells divide rapidly. With cancer, the abnormal cells grow quickly and can spread to other parts of the body. Noncancerous tumors grow slowly and don’t invade other parts of the body.

Doctors may not prescribe everolimus oral tablet in certain situations, such as to treat carcinoid tumors. Carcinoid tumors are a type of slow-growing neuroendocrine tumor.

Use for certain seizure disorders

Doctors may prescribe everolimus liquid suspension for focal onset seizures related to tuberous sclerosis (TS). It’s used for this purpose in adults and children ages 2 years and older. It’s usually prescribed as a long-term treatment and is used along with other antiseizure drugs.

TS is a genetic condition that causes noncancerous tumors in your body. It causes a wide range of symptoms that vary from person to person. Seizures are a common symptom of TS. And antiseizure medications, such as levetiracetam and topiramate, are typically used to manage seizures.

Use for prevention of organ rejection

Doctors may prescribe everolimus oral tablet to prevent kidney or liver transplant rejection. It’s used for this purpose in adults. It’s usually prescribed as a long-term treatment.

Transplant rejection occurs when your immune system attacks the transplanted organ. This happens because your immune system recognizes the new organ as something foreign in your body. There are a number of ways doctors try to prevent rejection from happening. One way is through prescribing medications that suppress your immune system. Everolimus oral tablet is prescribed at lower doses for this purpose.

Doctors may not prescribe everolimus oral tablet in certain situations, such as for:

• people who are at high risk of having a reaction against the donor kidney
• people who underwent transplantation with organs other than the kidney and liver
• children under the age of 18

What to ask your doctor

Let your doctor know if you have questions about everolimus or would like more details about it.

Here’s a list of some possible questions you may want to ask your doctor:

• How can I lower my risk of side effects from everolimus?
• How long will I take everolimus?
• Are there any drug interactions I should avoid while I’m taking everolimus?

Resources

• Everolimus tablets, for oral use. (2023). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/e3dbbc24-7e55-4069-a305-e2cded2db641/spl-doc
• Everolimus tablets, for oral use. (2023). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/d44998bb-5deb-4ee7-a0a5-979fe3f49557/spl-doc
• Everolimus tablets for oral suspension. (2022). https://nctr-crs.fda.gov/fdalabel/services/spl/set-ids/ca1a987e-f763-4026-93c5-c545ca95826c/spl-doc
• Food and Drug Administration. (2023). Orange Book: Approved drug products with therapeutic equivalence evaluations. https://www.accessdata.fda.gov/scripts/cder/ob/index.cfm   

Disclaimer: Optum Perks 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.