Verzenio's Side Effects: What to Know

Medically Reviewed By Brittany A. Duke, PharmD, RPh

Verzenio: Introduction

Verzenio is a brand-name prescription drug. It’s a type of medication called a kinase inhibitor and contains the active drug abemaciclib. It comes as a tablet that you’ll swallow.

Verzenio is approved by the Food and Drug Administration (FDA) for use in adults. It’s prescribed to treat breast cancer that’s all of the following:

Verzenio may be used in certain situations for treating this type of breast cancer. For a general overview of Verzenio, including details about its uses, see this article.

You’ll likely take Verzenio until either your cancer progresses or you have side effects that aren’t tolerable.

Similar to other drugs, Verzenio may cause side effects. Read below for information about possible side effects, including common, mild, and serious ones.

If you’d like to take Verzenio, search here to find a healthcare professional who might prescribe it.

Verzenio: More common side effects

Some of Verzenio’s side effects may be more common than others. These side effects may last only a few days to weeks. However, some side effects may last longer or become severe or bothersome. Tell your doctor or pharmacist if you have concerns about any side effects with Verzenio.

In Verzenio’s clinical studies, these were some side effects that occurred more often:

* For more information about this side effect, see “Verzenio: Side effects explained” below.

Verzenio: Mild side effects

Verzenio can cause mild side effects, which are listed below. However, this list doesn’t include all possible mild side effects. To learn more about Verzenio’s side effects, view the drug’s prescribing information.

Verzenio’s mild side effects include:

The side effects listed above may last only a few days to weeks. However, some side effects may last longer or become severe or bothersome. Tell your doctor or pharmacist if you have concerns about side effects with Verzenio.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you develop a side effect while taking Verzenio and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Verzenio: Side effects explained” below.
† An allergic reaction is possible after taking Verzenio. However, this side effect was not reported in clinical studies.

Verzenio: Serious side effects

It’s possible to have serious side effects with Verzenio. Serious side effects are listed below, but this list may not include all possibilities. To learn more about Verzenio’s side effects, view the drug’s prescribing information.

Call your doctor right away if you have serious side effects with Verzenio. However, if you think you’re having a medical emergency or have life threatening side effects, call 911 or your local emergency number.

Serious side effects of Verzenio and their possible symptoms include:

* For more information about this side effect, see “Verzenio: Side effects explained” below.
† An allergic reaction is possible after taking Verzenio. However, this side effect was not reported in clinical studies.

Verzenio: Side effects explained

Here’s detailed information about some of Verzenio’s side effects.

Diarrhea

Diarrhea was the most common side effect reported by people taking Verzenio in clinical studies. In fact, nearly everyone taking the drug had some degree of diarrhea.

Diarrhea was most common in the first month of treatment with Verzenio. And it lasted 5 to 11 days on average. In some instances, people needed their dose of the medication lowered to help relieve their diarrhea.

In some cases, diarrhea occurred in people who also had an infection as a side effect from Verzenio.

Diarrhea due to Verzenio can lead to dehydration. With this condition, you have a low level of fluid in your body.

What to do

If you have diarrhea while taking Verzenio, call your doctor. Their recommendation will depend on how severe your symptoms are.

If you have mild diarrhea, your doctor will likely have you take a medication to treat diarrhea. This could include loperamide (Imodium A-D), for example. They’ll also instruct you to drink plenty of fluids to avoid dehydration.

If your diarrhea is severe, your doctor will likely have you temporarily stop taking Verzenio until your symptoms ease. They’ll also prescribe a medication to treat the diarrhea. Once your symptoms ease, your doctor will likely restart your Verzenio treatment, but at a lower dose than before. It’s also possible they may have you stop taking the medication permanently and may recommend a different treatment option for you.

Hair loss

Hair loss or thinning was a side effect commonly reported by people taking Verzenio in clinical studies.

In some instances, Verzenio is prescribed with other medications to treat breast cancer. These can include medications that also cause hair loss as a side effect. Examples include anastrozole (Arimidex) and fulvestrant (Faslodex). You may have a higher risk of hair loss if you’re taking Verzenio in combination with these medications.

Hair loss caused by Verzenio and other cancer drugs can vary from person to person. Some people don’t have this side effect from the medication. Other people notice hair that’s thinner than is typical, while some people experience total hair loss.

Also, keep in mind that hair loss caused by Verzenio can affect different parts of the body. For some people, only hair on the head is affected. However, for other people, body areas including the eyebrows or arms can be affected.

What to do

Talk with your doctor if you’re concerned about hair loss while taking Verzenio. Your doctor can discuss strategies to help prevent or slow hair loss, such as using a cooling cap.

Lung problems

Treatment with Verzenio can cause serious lung problems. That said, these issues weren’t common in the drug’s clinical studies. In extreme cases, lung problems can be life threatening.

Specifically, both interstitial lung disease (ILD) and pneumonitis have been reported in people taking Verzenio. ILD and pneumonitis are conditions that both cause inflammation and scarring in the lungs.

Symptoms of ILD and pneumonitis can include:

What to do

Call your doctor if you develop symptoms of lung problems while taking Verzenio. Depending on the severity of your symptoms, your doctor may have you temporarily stop taking Verzenio. Then, they’ll restart your treatment at a lower dose than before and see if this helps your symptoms.

However, your doctor may have you permanently stop taking Verzenio if your symptoms are severe or don’t go away. In this case, your doctor can discuss alternative treatment options with you.

Liver problems

Although rare, Verzenio can cause liver problems as a side effect.

In the drug’s clinical studies, a small number of people had increased liver enzyme levels. Increased liver enzyme levels are often not a cause for concern, and they don’t typically cause symptoms. However, in rare cases, they can be a sign of liver damage. This is particularly true with severely high liver enzyme levels.

In Verzenio’s studies, if severely high liver enzyme levels occurred, they typically started a while after treatment was begun. If the drug was stopped or its dosage was reduced, it took a week or so for the enzymes to return to regular levels.

Symptoms of liver problems can include:

  • fatigue
  • pain in the upper right abdomen
  • loss of appetite
  • bruising or bleeding more easily than is typical

What to do

Tell your doctor if you have any symptoms of liver problems while taking Verzenio.

Your doctor will order a blood test to check your liver health before you start taking Verzenio. They’ll also order this test during your treatment with the drug.

Specifically, they’ll order a test to check your liver enzyme levels every 2 weeks for your first 2 months of treatment. Then, they’ll order this test monthly for the next 2 months. After that, they’ll periodically order the test as needed to check your liver.

If you notice symptoms of liver problems or your liver enzyme levels are high, your doctor may recommend one of the following:

  • temporarily stopping your Verzenio treatment
  • lowering your Verzenio dose
  • having you permanently stop taking Verzenio

Allergic reaction

As with most drugs, some people can have an allergic reaction after taking Verzenio. A more severe allergic reaction is rare but possible. However, this side effect was not reported in clinical studies.

Possible symptoms of mild and serious allergic reactions are listed in the table below.

Mild allergic reaction symptoms Serious allergic reaction symptoms
• itching trouble breathing
rash • swelling in your throat or mouth
flushing • swelling under your skin, possibly in your hands, feet, lips, or eyelids

If you have an allergic reaction to Verzenio, call your doctor right away. This is important to do because the reaction could become severe.

However, if you’re having a medical emergency or your symptoms feel life threatening, call 911 or a local emergency number.

Verzenio: Common questions about side effects

Here are some common questions about the drug’s side effects and answers to them. Talk with your doctor if you have other questions about this drug.

How long does it take Verzenio to work, and does this affect when Verzenio side effects may start?

It’s not known exactly how long it takes Verzenio to work. This is due to how the drug works, and because it’s difficult to know exactly when a drug for treating cancer “starts” working.

Instead, doctors monitor cancer over time to see if a treatment has stopped the cancer from growing or caused cancer tumors to shrink.

Some side effects caused by Verzenio, such as diarrhea, can begin during the first few days of treatment. Other side effects, including liver problems, may not appear for several weeks or months after starting the drug.

Talk with your doctor or pharmacist if you’d like to know more about Verzenio and when its side effects may start. Keep in mind that this can vary from person to person, and each person’s experience with Verzenio will be different.

Is it possible to have long-term side effects from Verzenio?

Yes, it’s possible to have long-term side effects with Verzenio. These are side effects that either:

  • start during treatment and continue for a long time, possibly after treatment ends
  • start after you’ve taken the drug for a long time or after treatment ends

Long-term side effects reported in Verzenio’s clinical studies included the following.

  • Blood clots. Although blood clots are treatable, they can cause long-term problems or require that you take medications for long-term treatment. That said, the risk of blood clots doesn’t appear to continue after Verzenio treatment is stopped.
  • Lung problems. Lung problems with Verzenio include interstitial lung disease and pneumonitis. These conditions can cause long-term scarring in the lungs that can’t be fully reversed. However, there are treatments that help slow the scarring and improve breathing.

Talk with your doctor or pharmacist if you’re interested in learning more about Verzenio and long-term side effects.

Does Verzenio cause any eye side effects?

It doesn’t appear so. Ocular (eye-related) side effects weren’t reported in Verzenio’s clinical studies. And these issues haven’t been reported since Verzenio was approved for use.

However, keep in mind that Verzenio may be taken by itself or in combination with other drugs. Examples include anastrozole (Arimidex) and fulvestrant (Faslodex).

Cataracts (cloudiness in the lens of the eye) have been reported with fulvestrant. Blurry vision, dry eye, and increased tears have been reported with anastrozole.

Talk with your doctor or pharmacist if you have questions about your risk of eye side effects with your cancer treatment plan.

Verzenio: Precautions

Be sure to talk with your doctor about your health history before you take Verzenio. This drug may not be the right treatment option for you if you have certain medical conditions or other factors that affect your health.

The conditions and factors to consider include those described below.

Active infection. Before you start treatment with Verzenio, be sure to talk with your doctor if you have an active infection. (Active infections cause symptoms.) Because the drug can weaken your immune system, it can make it harder for your immune system to fight off an infection. Taking Verzenio may cause your infection to be more difficult than is typical to treat. It’s likely your doctor will want to first treat the infection before prescribing Verzenio to you.

Blood clots. Rarely, Verzenio can cause blood clots as a side effect. If you’ve had a blood clot in the past, tell your doctor before you start treatment with Verzenio. It’s not known if having a past blood clot raises your risk of this side effect with Verzenio. Your doctor can help determine whether the medication is safe for you to take.

Kidney problems. Taking Verzenio can cause your creatinine level to rise. (Creatinine is a substance made naturally by your body that doctors measure to evaluate how well your kidneys are working.) For people without kidney problems, these creatinine increases often don’t cause problems. However, for people with existing kidney problems, such as chronic kidney disease, an increased creatinine level could further worsen kidney health. It’s generally safe for people with kidney problems to take Verzenio. Their doctor may monitor their kidney health closely during treatment, though.

Liver problems. Treatment with Verzenio can rarely cause liver problems as a side effect. If you already have liver problems, such as hepatitis, you may have a higher risk of this side effect. Your doctor can advise whether Verzenio is safe for you to take if you have liver problems. If they prescribe this drug to you, they may want to monitor your liver health closely during treatment. And this may require having blood tests often.

Blood cell problems, such as a low white blood cell level. Verzenio commonly causes blood cell problems, such as a low white blood cell level. In most cases, these blood cell problems are mild and treatable. If you have an existing blood cell problem, you may be at risk of having your condition worsen if you take Verzenio. Talk with your doctor about whether it’s safe for you to take Verzenio if you have a blood cell problem.

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

Consuming alcohol during Verzenio treatment

There’s no known interaction between alcohol and Verzenio.

However, both Verzenio and alcohol can increase liver enzyme levels. So combining the two may raise your risk of liver problems. (For more information about Verzenio and liver problems, see the “Verzenio: Side effects explained” section above.)

Alcohol may also increase your risk of other side effects of Verzenio, including diarrhea.

If you drink alcohol, talk with your doctor about how much, if any, is safe for you to drink while taking Verzenio.

Pregnancy and breastfeeding during Verzenio treatment

Verzenio isn’t safe to take during pregnancy. If you’re able to become pregnant, your doctor may order a pregnancy test to ensure you’re not pregnant before prescribing Verzenio for you.

Additionally, they’ll recommend that you use effective birth control while taking Verzenio and for at least 3 weeks after you take your last dose.

Breastfeeding while taking Verzenio isn’t recommended. This is because it isn’t known whether the drug passes into breast milk. That said, it’s thought Verzenio could cause severe side effects in a child who is breastfed if it does pass into breast milk. Talk with your doctor about safer feeding options for your child.

Verzenio: What to discuss with your doctor

Talk with your doctor or pharmacist to find out more information about Verzenio. If you have questions about the drug’s side effects, your pharmacist or healthcare professional can help answer them for you.

In addition to discussing Verzenio with your doctor, you may find the following articles helpful in learning more.

  • Overview of Verzenio. To read an overview of Verzenio, see this article.
  • Drug comparison. To learn how Verzenio compares with Ibrance, read this article.
  • Details about breast cancer. To learn more about breast cancer, which Verzenio is used to treat, see this article.

Disclaimer: Healthgrades 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.

Medical Reviewer: Brittany A. Duke, PharmD, RPh
Last Review Date: 2022 Jun 7
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.