9 Everolimus (Afinitor) Side Effects You Should Know About

Everolimus (Afinitor) is an oral medication that treats certain types of cancer. Everolimus is also available at lower doses under the brand name Zortress, which helps prevent organ rejection after a transplant. But the focus of this article is Afinitor. 

If you’ve been prescribed everolimus, you may be wondering what to expect while taking it. Here, we’ll look at nine possible everolimus side effects and how to manage them.

Side effects at a glance

Below, there are overview lists of the common and serious side effects you may experience while taking everolimus. If any of your side effects become bothersome, in many cases, your provider will lower your dose or pause treatment until your symptoms improve.

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Common side effects of everolimus include:

• Mouth sores

• Infections

• Rashes or itchy skin

• Fatigue

• Diarrhea

• Nausea

• Low appetite

• Stomach pain

• Swelling

• Weakness

• Menstrual changes

• Increased blood glucose levels

• Increased blood lipids

• Increased liver enzymes

Serious side effects of the medication include:

• Pneumonitis (inflammation of the lungs)

• Severe allergic reactions

• Low blood cell counts

• Kidney failure

Let’s look at some of these side effects in greater detail.

1. Mouth sores

Mouth sores are one of the most common everolimus side effects. You may also have swollen gums or a burning sensation in your mouth. These symptoms usually occur during the first 2 months of treatment. And they can be painful and make it hard to eat or drink normally.

You can help prevent or manage mouth sores by following these steps:

• Gently brush your teeth and tongue using a soft toothbrush after each meal.

• Floss daily.

• Avoid spicy, salty, and crunchy foods, which could irritate your mouth.

• Swish with a mixture of baking soda and salt water or an over-the-counter (OTC) rinse for mouth sores throughout the day.

• Ask your healthcare provider if a prescription mouthwash, such as “magic mouthwash,” is right for you.

Check your mouth regularly while you’re taking everolimus. And let your healthcare provider know right away if you notice any mouth sores or have pain. They may recommend a lower everolimus dose or a pause in treatment while your mouth heals.

2. Nausea and vomiting

Like many cancer treatments, everolimus can cause nausea and vomiting. Follow your healthcare provider’s instructions for managing these side effects. The American Cancer Society also has tips that might help.

Reach out to your provider before your next appointment if you have trouble keeping food down, feel dizzy, or lose weight quickly. They may recommend a nausea medication or a change in your everolimus treatment.

3. Diarrhea

Diarrhea is another common everolimus side effect. You can often manage mild diarrhea on your own by drinking beverages with electrolytes and sticking to a bland diet. Your healthcare provider may also recommend an OTC diarrhea medication, such as loperamide (Imodium AD). 

Keep in mind that severe diarrhea can lead to dehydration, and in rare cases it can be life-threatening. Symptoms of dehydration include dry mouth, headaches, and dark-yellow urine. If you notice these symptoms, let your provider know right away. You should also reach out to your provider if your diarrhea worsens or doesn’t improve after a few days.

4. Increased risk of infection

Another potential everolimus side effect is an increased risk of infections. The medication can weaken your immune system, which makes it harder for your body to fight off invaders. This can cause you to get sick more often or have infections that last longer than usual.

You can take steps to help prevent infections. Wash your hands often, avoid close contact with people who are sick, and disinfect household items (such as doorknobs and light switches). It may also be a good idea to wear a face mask in crowded spaces to help protect yourself.  And be sure you’re up to date on your vaccines before you start taking everolimus.

Contact your healthcare provider at the first sign of an infection, such as a cough or fever. They may decide to pause treatment with everolimus until you’re feeling better.

5. Low blood counts

Everolimus can lower the amount of different blood cells in your body. Your healthcare provider will likely check your blood count often to watch for this. But there are symptoms you can watch out for, too.

It’s common for everolimus to make people feel tired or weak. But severe fatigue may be due to a low red blood cell count (anemia). If your white blood cell count is low, your risk for infections goes up, as discussed above. Everolimus can also lower your platelet count, which makes it easier for you to bleed or bruise.

Remember to listen to your body and rest when you need to. And try to stay hydrated and eat regularly to keep your energy levels up. If you’re able, taking a walk outside can also give you a boost.

Contact your healthcare provider if you have severe weakness, trouble breathing, or any unusual bleeding or bruising. They may recommend a change or pause in your treatment if your blood counts are too low. 

6. Body rash

It’s common to develop an itchy rash during the first few months of treatment with everolimus. This rash can appear on your head, face, and neck, as well as your arms, legs, and trunk.

Regular use of a thick moisturizer, such as Aquaphor or Eucerin, can help protect your skin and lessen itching. And be sure to use sunscreen with an SPF of at least 15 when you’re outdoors.

Let your provider know if you develop a rash while taking everolimus. If it’s mild, your provider may recommend an OTC antihistamine or steroid cream or a prescription treatment. But if the rash is severe, you may need a lower everolimus dose or a break from treatment. Your provider will help you decide what’s best.

7. Increased blood glucose and blood lipids

Over 70% of people taking everolimus have an increase in their blood glucose (sugar) and blood lipids (fats, cholesterol). In many cases, these increases don’t cause any noticeable symptoms. But they may still need to be addressed. So your healthcare provider will likely check your blood glucose and blood lipids before you start taking everolimus and regularly thereafter. And you may need other medications to help manage high levels.

But if your blood glucose or lipid levels don’t improve, your provider may lower your everolimus dose or stop treatment altogether.

8. Lung issues

A more serious everolimus side effect is inflammation of the lungs, also called pneumonitis. Up to 19% of people taking the medication develop this side effect.

You may not always have symptoms with pneumonitis, but in most cases it causes a cough and trouble breathing. As mentioned, everolimus can also increase your risk of infection, so it may be hard to know what’s causing your symptoms. Let your provider know if you begin to cough or wheeze at any time during treatment. They may need to lower your dose or hold treatment until your symptoms resolve.

9. Kidney failure

Rarely, taking everolimus can lead to kidney failure. This is a severe side effect that requires immediate medical attention. Symptoms include peeing less often, swelling in the legs or feet, and feeling weak.

Your healthcare provider will likely keep an eye on your kidney function while you’re taking everolimus. But if you experience the above symptoms, contact your provider right away.

When should I contact my healthcare provider about everolimus side effects?

It’s best to let your provider know about any side effects that you experience while you’re taking everolimus. This will help them monitor how you’re doing with the medication and determine if you need a lower everolimus dose or a pause in treatment.

Contact your provider right away if you have any of the following symptoms:

• Trouble breathing

• A fever that doesn’t go away

• Severe cough

• Severe fatigue

• Unusual bleeding or bruising

• Severe dizziness

• Trouble peeing

Don’t hesitate to seek emergency care for any side effects that feel severe or life-threatening.

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Written by:

Alex Evans, PharmD, MBA

Alex Evans, PharmD, MBA, has been a pharmacist for 12 years. His first job was floating in a community chain pharmacy.

Edited by:

Stacia Woodcock, PharmD

Stacia Woodcock, PharmD, is a pharmacy editor for GoodRx. She earned her Doctor of Pharmacy degree from the University of Kentucky and is licensed in New York and Massachusetts.

Reviewed by:

Daphne Berryhill, RPh

Daphne Berryhill, RPh, has two decades of experience as a clinical pharmacist. She spent most of her career in the Chicago area practicing in-home infusion.

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