8 Ibrance Side Effects and How to Manage Them

Ibrance (palbociclib) is a convenient, once-daily oral breast cancer medication. It treats a specific form of breast cancer called hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+/HER2-) advanced or metastatic breast cancer. 

Even though it treats cancer, Ibrance isn’t a chemotherapy medication. It’s a type of targeted therapy known as a cyclin-dependent kinase 4 and 6 (CDK 4/6) inhibitor. And it’s usually taken in combination with hormone therapy. By blocking CDK 4 and CDK 6 enzymes (proteins), Ibrance helps slow the growth of breast cancer cells.

Ibrance fights cancer with a strategic approach. But it can still cause some relatively significant side effects. Most side effects are mild and manageable, but serious risks are also possible.

Ibrance side effects at a glance

As with all medications, Ibrance can cause side effects. The most common Ibrance side effects include:

• Fatigue

• Weakness

• Nausea

• Diarrhea

• Lower appetite

• Lower blood cell counts

• Infections

• Mouth sores

• Hair loss

• Vomiting

• Skin rashes

• Dry skin

Rare, but serious Ibrance side effects include:

• Serious infection

• Lung inflammation

Here’s a closer look at how to manage eight notable Ibrance side effects.

1. Fatigue

Fatigue is one of the most common side effects of Ibrance. About 40% of people who took it in clinical studies reported feeling tired.

If you’re feeling tired while taking Ibrance, there are a few things you can try to help boost your energy:

• Perform light exercise daily, which can be energizing.

• Listen to your body — take short naps or breaks when you feel tired.

• Stay well hydrated and eat a healthy, balanced diet to keep you fueled throughout the day.

• Schedule activities when you have the most energy.

• Ask people in your inner circle for support managing daily tasks or chores.

Talk to your healthcare provider if tiredness becomes unmanageable while taking Ibrance. They may be able to recommend other ways to manage your energy levels.

2. Diarrhea

Diarrhea is another common side effect of Ibrance. It happened in a quarter of people who took it in initial studies.

If you experience diarrhea while taking Ibrance, there’s a few ways to manage it. At the first sign of a loose stool, you can take an over-the-counter antidiarrheal, such as loperamide (Imodium A-D). It’s also important to stay well hydrated with non-sugary liquids to help replenish lost fluids and electrolytes. Also, try to avoid spicy and greasy trigger foods — they can make diarrhea worse.

Let your healthcare provider know if your diarrhea doesn't resolve within about 24 hours. Depending on how severe the diarrhea is, they may recommend that you temporarily stop taking Ibrance and restart it at a lower dose once the diarrhea goes away.

3. Nausea

Like many other cancer medications, Ibrance can cause nausea. A few tips to help manage nausea from Ibrance include eating more frequent smaller meals, temporarily eating bland foods (like toast or crackers), and relaxing with meditation or deep breathing. 

If you’re feeling really nauseous, let your healthcare provider know. Cancer specialists are very familiar with anti-nausea medications. They may recommend an anti-nausea medication, such as ondansetron (Zofran) or prochlorperazine, to help combat nausea.

4. Changes in blood cell counts

Ibrance can cause your blood cell counts to drop. This includes your white blood cells, red blood cells, and platelets. Of these, Ibrance has the greatest effect on lowering white blood cell counts.

When your red blood cells or platelets are lower than normal, you may bruise or bleed more easily. When white blood cell counts are lower than normal, it’s easier to get sick. This is also when serious infections can happen — and some can be life-threatening.

Because of these risks, your healthcare provider will check your blood cell counts before you start taking Ibrance. They’ll also check them regularly while you’re taking it. If your blood cell counts become too low, your provider may recommend you stop taking Ibrance or lower your dosage.

5. Infection

Because Ibrance causes low white blood cells, it can weaken your immune system. When certain types of white blood cells (called neutrophils) get too low, it can lead to a serious condition called neutropenia. Neutropenia tends to happen after about 2 weeks of taking Ibrance and can last for about a week.

People with neutropenia are at a higher risk of developing a serious infection. Having a fever while you’re neutropenic, also known as febrile neutropenia, is especially serious. 

If you develop neutropenia while taking Ibrance, your healthcare provider will likely have you temporarily stop taking it to allow your white blood cell counts to recover. They may also lower your dose. Neutropenia usually happens less frequently over time as you continue to take Ibrance.

You should let your provider know if you have symptoms of an infection, such as fever, chills, or a new cough. This is especially important if you’re neutropenic, as infections can become serious and need to be treated right away.

It’s also important to try to protect yourself from getting sick while taking Ibrance. Some ways to do this are washing your hands often, wearing a facemask in public places, and avoiding crowded areas and people who are sick.

6. Mouth sores

Ibrance can cause mouth sores and ulcers. This can lead to mouth pain that makes it difficult to eat and drink.

These mouth sores can affect your quality of life. Here are some tips to help manage the discomfort:

• Keep your mouth clean and brush your teeth with a soft toothbrush.

• Avoid alcohol and acidic or spicy foods.

• Avoid crunchy foods that may cut the inside of your mouth.

• Stay hydrated.

• Try to avoid dry mouth symptoms; consider chewing sugar-free gum or sucking on ice chips.

If mouth sores become hard to tolerate, let your healthcare provider know. They may recommend a magic mouthwash, which is an oral rinse that contains several different soothing medications.

7. Hair loss

In clinical studies, over one-third of people taking Ibrance experienced some degree of hair loss. It’s rare to have total hair loss with Ibrance. Hair thinning is more common.

Keep these tips in mind if you experience hair thinning while taking Ibrance:

• Limit hair treatments like chemical hair dyes or straighteners.

• Only use shampoos that are labeled as mild, gentle, or sulfate free.

• Be gentle when brushing or combing your hair.

• Avoid overusing heat styling tools, such as curlers and hair dryers.

• Get a haircut in a new style or try a wig.

• Wear a scarf or hat on your head to stay warm.

Let your healthcare provider know if you’re concerned about hair loss while taking Ibrance. They may be able to recommend other hair loss treatment options.

Keep in mind: Ibrance isn’t the only possible cause of hair loss. Hormone therapy you’re taking with Ibrance may also contribute to hair loss.

8. Lung-related risks

Rarely, Ibrance can cause interstitial lung disease (ILD). This is a type of lung inflammation. ILD can be life-threatening if it happens. 

Let your healthcare provider know if you experience any new or worsening respiratory symptoms, including shortness of breath, cough, or chest pain, while taking Ibrance. They may ask you to temporarily stop taking Ibrance while they assess your lungs. 

If you develop severe ILD while taking Ibrance, you’ll likely need to stop taking it altogether.

When should you contact your cancer specialist about Ibrance side effects?

Many of Ibrance’s side effects are mild and improve on their own over time. But some side effects are serious. Contact your cancer specialist if any side effects are hard to tolerate or worsen at any point.

If you think you're having a serious side effect of Ibrance, seek medical attention right away. Be on the lookout for symptoms such as:

• Trouble breathing

• Shortness of breath

• Sudden or worsening cough

• Chest pain

• Easy bruising

• Bleeding

• Fever

• Chills

Why trust our experts?

Written by:

Sonja Jacobsen, PharmD, BCPS, BCOP

Sonja Jacobsen, PharmD, BCPS, BCOP,  is a clinical oncology pharmacy specialist currently practicing in Seattle. She has been practicing as a pharmacist since 2015 and is licensed to practice in Washington state and North Carolina.

Edited by:

Joshua Murdock, PharmD, BCBBS

Joshua Murdock, PharmD, BCBBS, is a licensed pharmacist in Arizona, Colorado, and Rhode Island. He has worked in the pharmacy industry for more than 10 years and currently serves as a pharmacy editor for GoodRx.

Reviewed by:

Vanessa Carranza, PharmD

Vanessa Carranza, PharmD, is a pharmacist who has dedicated her career to the advancement of medical education for healthcare providers, patients, and caregivers, most notably in the oncology space.

Our editorial standards

Meet our experts