Ibrance (palbociclib) is a prescription drug that’s used to treat certain types of breast cancer. Ibrance can cause side effects that range from mild to serious. Examples include skin rash, infections, and inflammation or scarring in the lungs.

Ibrance is used in adults to treat advanced or metastatic breast cancer that is also hormone receptor-positive and HER2-negative.

Ibrance comes as either a tablet or a capsule that you take by mouth. If Ibrance works for you, it’s likely that you’ll take it long term.

Ibrance is taken along with other medications to treat your breast cancer. It can be used with either fulvestrant (Faslodex) or an aromatase inhibitor, such as letrozole (Femara) or anastrozole (Arimidex), based on your specific condition.

For more information about Ibrance, including details about its uses, see this article.

As with other drugs, Ibrance can cause mild or serious side effects. Keep reading to learn more.

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

  • fatigue (low energy)
  • nausea, vomiting, or diarrhea
  • hair loss
  • fever
  • skin rash*
  • infections

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

Ibrance may cause mild side effects in some people. Examples of mild side effects that have been reported with Ibrance include:

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

Some of these side effects may be easily managed. But if you have any symptoms that are ongoing or that bother you, talk with your doctor or pharmacist. Don’t stop using Ibrance unless your doctor recommends it.

Ibrance may cause mild side effects other than the ones listed above. For details, see the prescribing information for Ibrance capsules and tablets.

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 Ibrance, visit MedWatch.

Serious side effects that have been reported with Ibrance include:

* To learn more about this side effect, see “Side effects explained” below.
? An allergic reaction is possible after using Ibrance. But it’s not clear whether this side effect occurred in studies.

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

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

Are there any foods I should avoid while taking Ibrance?

Yes, you should avoid grapefruit and grapefruit juice while taking Ibrance. Grapefruit and grapefruit juice can cause the levels of Ibrance in your body to become too high. This may increase your risk of side effects from Ibrance.

If you have questions about foods to avoid during Ibrance treatment, talk with your doctor.

Does Ibrance cause any eye-related side effects?

Although uncommon, it’s possible that Ibrance may cause ocular (eye-related) side effects. In studies, people taking Ibrance with either letrozole (Femara) or fulvestrant (Faslodex) reported blurry vision and dry eye. (For information on these studies, see the prescribing information for Ibrance capsules and tablets.) In addition, people taking Ibrance experienced an increase in tear production.

In most cases, eye-related side effects from Ibrance were mild.

But other medications used to treat breast cancer may cause more serious eye-related side effects. For example, tamoxifen (Soltamox) can cause:

  • changes in color vision
  • disease of the retina, which may cause vision loss
  • cataracts
  • retinal vein thrombosis (a blood clot in the retina)
  • changes to your cornea

If you have questions or concerns about eye-related side effects from taking Ibrance, talk with your doctor or pharmacist.

When do side effects from Ibrance typically start?

It depends. Ibrance can reach its highest concentration up to 12 hours after you take your dose. So symptoms such as nausea or vomiting may occur at that time.

Other side effects, such as liver damage, may take longer to occur. Your doctor will monitor you throughout your treatment for symptoms of any side effects.

If you have questions about when you may experience certain side effects from Ibrance, talk with your doctor or pharmacist.

Does Ibrance cause any long-term side effects?

It’s possible that Ibrance can cause long-term side effects. However, long-term side effects weren’t reported in studies of the drug. (For information on these studies, see the prescribing information for Ibrance capsules and tablets.)

Examples of long-term side effects that may occur from Ibrance treatment include:

If you’re concerned about your risk of long-term side effects from taking Ibrance, talk with your doctor. They can help monitor you during your treatment. If you do begin to develop these side effects, your doctor may recommend ways to treat them or other medications to treat your breast cancer.

Could Ibrance cause any cardiac (heart-related) side effects?

No, Ibrance is not known to cause any heart-related side effects. These were not reported in studies of people taking Ibrance. (For information on these studies, see the prescribing information for Ibrance capsules and tablets.)

But other medications used to treat breast cancer, such as ribociclib (Kisqali), may cause heart-related side effects. For example, Kisqali can cause long QT syndrome (atypical electrical activity in your heart).

If you think you’re experiencing heart problems during your Ibrance treatment, talk with your doctor. They can determine what may be causing the problem and the best way to treat it.

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

Inflammation or scarring in your lungs

It’s possible to develop pneumonitis (inflammation in your lungs) from taking Ibrance. This drug may also cause interstitial lung disease (scarring of lung tissue).

Inflammation and scarring in the lungs were rare in studies of Ibrance, but these side effects can be life threatening if they occur. (For information on these studies, see the prescribing information for Ibrance capsules and tablets.)

During your Ibrance treatment, you should watch for symptoms of lung inflammation or scarring. These may include:

  • cough
  • trouble breathing
  • feeling tired or weak
  • unexplained weight loss

What might help

If you experience any of the symptoms listed above, tell your doctor right away. They’ll likely do tests to determine whether you’re developing interstitial lung disease or pneumonitis. If you do develop either condition, your doctor will have you stop taking Ibrance and switch to a different medication.

Skin rash

Some people may develop a rash from taking Ibrance. In studies, this was one of the most common side effects that people taking Ibrance reported. (For information on these studies, see the prescribing information for Ibrance capsules and tablets.)

Symptoms of a rash may include:

  • itching
  • redness or discoloration
  • swelling
  • blistering

What might help

If you develop a rash from taking Ibrance, talk with your doctor. A rash is usually not serious. But in some cases, it can cause blistering and may become serious. It’s also possible that a rash may be a sign of an allergic reaction. Your doctor can determine how serious your rash is, and they can recommend treatment for it if needed.

Mouth sores or mouth pain

Some people may develop sores or pain in their mouth while taking Ibrance. This was a common side effect reported by people taking Ibrance in studies. (For information on these studies, see the prescribing information for Ibrance capsules and tablets.)

Throughout your Ibrance treatment, watch for mouth sores or pain. Other symptoms to be aware of include:

  • swelling inside your mouth
  • chapped lips
  • swelling of your tongue

What might help

If you develop mouth sores or pain while taking Ibrance, tell your doctor. They may be able to recommend treatment to relieve your symptoms.

Changes in results of liver function tests

It’s possible that taking Ibrance can cause changes in the results of your liver function tests. Specifically, Ibrance may increase blood levels of certain liver enzymes. (Enzymes are proteins that aid chemical changes in your body.) This may be a sign of liver disease or liver damage.

Although not as common as other lab abnormalities, changes in liver function test results were reported in studies of Ibrance. (For information on these studies, see the prescribing information for Ibrance capsules and tablets.)

During your Ibrance treatment, you should watch for symptoms of liver damage. Symptoms may include:

  • jaundice (yellowing of the skin or the whites of your eyes)
  • abdominal pain
  • nausea

What might help

Your doctor will monitor your liver function throughout your Ibrance treatment. If your liver function tests show changes, your doctor may recommend more testing to determine the cause. In some cases, they may have you stop taking Ibrance and switch to a different medication.

If you develop symptoms of liver damage, tell your doctor right away. They can do testing to determine what may be causing your symptoms.

If you have concerns about liver damage while you’re taking Ibrance, talk with your doctor.

Allergic reaction

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

Symptoms can be mild or serious and may include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin, typically 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 an over-the-counter oral antihistamine, such as Benadryl (diphenhydramine), or a topical product, such as hydrocortisone cream, to manage your symptoms.

If your doctor confirms you had a mild allergic reaction to Ibrance, they’ll decide whether 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 had a serious allergic reaction to Ibrance, they may have you switch to a different treatment.

Keeping track of side effects

During your Ibrance treatment, consider keeping notes on any side effects you’re having. Then, you can share this information with your doctor. This is especially helpful to do 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 drug you were taking when you had the side effect
  • how soon after starting that dose you had the side effect
  • what your symptoms were from the side effect
  • how it affected your daily activities
  • what other medications you were also taking
  • any other information you feel is important

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

Ibrance may not be right for you if you have certain medical conditions or other factors that affect your health. Talk with your doctor about your health history before you take Ibrance. The list below includes factors to consider.

Current infection. If you currently have any infections, be sure to tell your doctor before you start taking Ibrance. This drug may weaken your immune system, which can make it harder for your body to fight an infection after you start Ibrance treatment. If you currently have an infection, your doctor will likely treat it before you start taking Ibrance.

Lactose intolerance. Ibrance capsules contain lactose. If you have lactose intolerance, tell your doctor. They’ll likely prescribe the Ibrance tablets instead for your condition, as the tablets do not contain lactose.

Allergic reaction. If you’ve had an allergic reaction to Ibrance or any of its ingredients, you shouldn’t take Ibrance. Ask your doctor what other medications are better options for you.

Liver problems. If you have liver problems, tell your doctor before taking Ibrance. This medication may increase your risk of liver damage. If you already have a liver condition, Ibrance may make it worse. Talk with your doctor to see whether Ibrance is a safe treatment option for you.

Lung problems. Ibrance may cause inflammation or scarring in your lungs. If you currently have a lung condition, talk with your doctor before starting Ibrance treatment. This medication may make your lung condition worse. Your doctor may want to monitor you more closely during your treatment, or they may recommend a different treatment for you.

Alcohol use and Ibrance

There are no known interactions between Ibrance and alcohol. But alcohol may make some of the side effects of Ibrance worse.

For example, Ibrance can cause nausea or vomiting, or more serious side effects such as liver problems. Alcohol can also cause nausea or vomiting, so these symptoms may worsen if you drink alcohol while taking Ibrance. In addition, alcohol can damage your liver, so drinking alcohol while taking Ibrance may increase your risk of liver damage.

If you drink alcohol, talk with your doctor about how much (if any) is safe for you to drink during your Ibrance treatment.

Pregnancy and breastfeeding while taking Ibrance

You should not take Ibrance if you’re pregnant or planning to become pregnant. This medication can cause harm to a fetus.

Because of this risk, if you’re female* and can become pregnant, your doctor will give you a pregnancy test before you start taking Ibrance. You’ll also need to use birth control during your treatment and for at least 3 weeks after your last dose of Ibrance.

If you’re male* and sexually active with a partner who can become pregnant, you should also use birth control while taking Ibrance and for at least 3 months after stopping treatment.

It’s not known whether Ibrance is safe to take while breastfeeding. Studies haven’t looked at whether the drug passes into breast milk or what effects it may have on a child who is breastfed. But because of the risk of harm to a fetus, Ibrance use is not recommended while breastfeeding. You also shouldn’t breastfeed for at least 3 weeks after your last dose of Ibrance.

If you’re pregnant or breastfeeding, or planning to become pregnant or to breastfeed, talk with your doctor before taking Ibrance.

* In this article, we use the terms “male” and “female” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, see this article.

You may experience side effects during your Ibrance treatment. Most side effects are usually mild, but in rare cases, serious side effects could occur.

Before taking Ibrance, you should talk with your doctor about your risk of side effects and any other questions that you have. Examples of questions you may want to ask include:

  • Do I have a higher risk of side effects because of the other medications I take?
  • How should I manage side effects that I experience from Ibrance?
  • What should I do if I become pregnant while taking Ibrance?

To learn more about Ibrance, see these articles:

To get information on different conditions and tips for improving your health, subscribe to any of Healthline’s newsletters. You may also want to check out the online communities at Bezzy. It’s a place where people with certain conditions can find support and connect with others.

Q:

Can my dose be decreased if I’m experiencing negative side effects from Ibrance?

Anonymous

A:

Yes, it’s possible your dose of Ibrance could be decreased if you experience side effects. This may depend on the specific side effect you experience and how severe it is.

You should talk with your doctor about any side effects that you have while taking Ibrance so they can determine whether your dose should be adjusted.

The Healthline Pharmacist TeamAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

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.