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Nerlynx

neratinib

Used for Breast Cancer

Nerlynx (neratinib) is an oral medication that treats HER2-positive breast cancer. Depending on the stage of breast cancer, it’s taken by itself (early stage) or together with another anticancer medication (advanced or metastatic stage). Nerlynx (neratinib) is typically used for people who’ve received other previous breast cancer treatments. It’s conveniently taken once a day, but usually causes diarrhea.

Reviewed by:

Lauren Morton, PharmD, BCPS

Cydnee Ng, PharmD

Last reviewed on December 15, 2022

Basics Side effects Pros & cons Pharmacist tips FAQs Warnings Dosage Alternatives Latest news Images Prices Medicare

What is Nerlynx (neratinib)?

What is Nerlynx (neratinib) used for?

HER2-positive breast cancer

How Nerlynx (neratinib) works

Nerlynx (neratinib) is a kinase inhibitor. It works by blocking the action of specific proteins called human epidermal growth factor receptor 2 (HER2) and epidermal growth factor receptor (EGFR). HER2 and EGFR are both found on normal and cancer cells, and they play a role in cell growth.

In some cancers like HER2-positive breast cancer, the cancer cells have more HER2 and EGFR proteins than normal cells. When these proteins are blocked by Nerlynx (neratinib), the cancer cells can’t grow and spread as well.

Are you looking for information on Zejula (niraparib) instead?

Drug Facts

Common BrandsNerlynx

Drug ClassKinase inhibitor

Controlled Substance ClassificationNot a controlled medication

Generic StatusNo lower-cost generic available

AvailabilityPrescription only

What are the side effects of Nerlynx (neratinib)?

The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

Common Side Effects

Diarrhea (up to 95%)
Nausea (up to 53%)
Vomiting (up to 46%)
Tiredness (up to 45%)
Stomach pain (up to 36%)
Lower appetite (up to 35%)
Constipation (up to 31%)
Weight loss (up to 20%)
Rash (up to 18%)
Redness, pain, or swelling inside of the mouth (up to 14%)
Dizziness (up to 14%)

^*These side effects happened when Nerlynx (neratinib) was taken by itself or together with other chemotherapy.^

Other Side Effects

Indigestion
Swelling of the stomach area
Muscle spasms
Back or joint pain
Symptoms of urinary tract infection (e.g., pain while urinating, needing to urinate more often)
Infection of the sinuses or throat (upper respiratory tract infection)
Nail changes
Dry skin
Dry mouth

Serious Side Effects

Contact your healthcare provider immediately if you experience any of the following.

Severe diarrhea
Liver damage: yellowing of skin or whites of your eyes, dark-colored urine, right upper stomach pain or discomfort

Source: DailyMed

The following side effects have also been reported

Side effects that you should report to your care team as soon as possible:

Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
Severe or prolonged diarrhea

Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):

Change in nail shape, thickness, or color
Fatigue
Loss of appetite with weight loss
Muscle spasms
Nausea
Pain, redness, or swelling with sores inside the mouth or throat
Stomach pain

Pros and cons of Nerlynx (neratinib)

Pros

Available as pills that are swallowed once a day

A treatment option if you have metastatic breast cancer and you’ve already tried other medications that didn’t work

Can be used to further help lower the risk of the cancer coming back after surgery if you have early-stage breast cancer

Cons

Must take many pills all at once each day

Commonly causes diarrhea, so you might have to also take an antidiarrheal medication called loperamide (Imodium A-D)

Only available as a brand medication

Pharmacist tips for Nerlynx (neratinib)

Take Nerlynx (neratinib) once a day at the same time each day. Don’t chew, split, or crush the tablets before swallowing to make sure the medication works the way it should.

Take your Nerlynx (neratinib) dose with food each day. This helps the medication get absorbed into your body better.

If you miss a dose of Nerlynx (neratinib), don’t take any tablets that day. Wait and take your next dose the next day at your usual time.

Since Nerlynx (neratinib) commonly causes diarrhea, your provider might give you instructions to take an antidiarrheal medication called loperamide (Imodium A-D) along with your Nerlynx (neratinib) treatment (either regularly or on an as-needed basis). Other things you can do to help include avoiding spicy and greasy foods and eating small meals with foods that are easier on the stomach.

Drink plenty of fluids (e.g., water, broth) to avoid dehydration from possible diarrhea. Let your provider know during treatment if you get dehydrated (e.g., dry mouth, not urinating as much, lightheadedness, dizziness).

If you need to take heartburn medications, take them at different times than Nerlynx (neratinib) or avoid them altogether, since they can affect how well the cancer medication works. Take Nerlynx (neratinib) 3 hours after antacids like calcium carbonate (Tums). Also, take Nerlynx (neratinib) at least 2 hours before or 10 hours after medications like famotidine (Pepcid AC). But avoid proton pump inhibitors (PPIs) like omeprazole (Prilosec) during Nerlynx (neratinib) treatment.

Whether you’re female or male, if you’re taking Nerlynx (neratinib) and you or your partner is able to become pregnant, use birth control during treatment and for at least 1 month (for females) or 3 months (for males) after your last dose. Let your provider know right away if you or your partner becomes pregnant during this time

Ask your provider or pharmacist about the best way to handle and throw away Nerlynx (neratinib) safely. Cancer medications can be very harmful to anyone who handles or comes into contact with them.

Frequently asked questions about Nerlynx (neratinib)

Why do some people start at a low dose of Nerlynx (neratinib) when beginning treatment?

To help manage having diarrhea from Nerlynx (neratinib), your provider might start you at a lower dose (3 tablets daily), and then slowly raise it up to the typical dose (6 tablets daily) over 2 weeks. This is an alternative dosing option compared to starting treatment at the typical dose right off the bat along with taking the antidiarrheal medication loperamide (Imodium A-D) regularly for at least the first 2 months of treatment. Talk with your provider about the best dosing strategy for you.

How long can you take Nerlynx (neratinib)?

For early-stage breast cancer, you typically continue treatment until the cancer comes back. But keep in mind that treatment with Nerlynx (neratinib) is also limited to 1 year for this stage of breast cancer, since there haven’t been any studies about how well the medication works or how safe it is beyond that time. On the other hand, for advanced or metastatic breast cancer, you typically continue treatment as long as Nerlynx (neratinib) is preventing your cancer from getting worse. But in general, if you don’t tolerate Nerlynx (neratinib) well, experience certain side effects like severe diarrhea, or your provider determines the medication is causing liver problems, your care team will discuss with you about what this means and if you need to stop treatment. Don’t stop taking Nerlynx (neratinib) without talking with your healthcare provider first.

Does Nerlynx (neratinib) cause hair loss?

In clinical studies, hair loss wasn’t a reported side effect of Nerlynx (neratinib). Hair loss is more commonly related to other anticancer medications for breast cancer like docetaxel (Taxotere) and paclitaxel. If you experience hair loss during Nerlynx (neratinib) treatment, contact your provider so they can check what’s causing it and address your concerns.

Is Nerlynx (neratinib) a chemotherapy medication?

Nerlynx (neratinib) isn’t considered chemotherapy. Chemotherapy medications kill cancer cells in your body. Nerlynx (neratinib) doesn’t kill cancer cells, but rather slows or stops cancer cells from growing.

Is it safe to breastfeed while taking Nerlynx (neratinib)?

It isn’t recommended to breastfeed while taking Nerlynx (neratinib). It's not known if the medication can be found in breast milk, but there’s a risk of serious harm to nursing infants if it is. Because of this risk, don’t breastfeed during Nerlynx (neratinib) treatment and for at least 1 month after your last dose. Talk with your provider if you have any questions about breastfeeding or recommendations for other ways to feed your baby while taking Nerlynx (neratinib).

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What are the risks and warnings for Nerlynx (neratinib)?

Nerlynx (neratinib) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.

Diarrhea

Most people taking Nerlynx (neratinib) have diarrhea during treatment. Diarrhea typically happens within the first month of treatment and lasts less than a week. Though rare, severe cases of diarrhea can sometimes lead to dehydration, very low blood pressure, and kidney damage. To prevent, manage, and treat diarrhea, your provider will likely instruct you to take an antidiarrheal medication such as loperamide (Imodium A-D) along with your Nerlynx (neratinib) treatment. Let your provider know if you begin to have any diarrhea. They might adjust your antidiarrheal medication, lower your Nerlynx (neratinib) dose, or stop your Nerlynx (neratinib) treatment.

Liver damage

Nerlynx (neratinib) can cause liver damage. Your provider will track your liver health through lab work while you’re taking this medication. Let your provider know if you develop any symptoms of liver problems, such as yellowing of skin or whites of your eyes, dark urine, and pain or discomfort in the right upper stomach area. Your provider might lower your Nerlynx (neratinib) dose, pause, or stop your treatment.

Harm to unborn baby

Nerlynx (neratinib) might cause harm to an unborn baby. If you're a female who can get pregnant, your provider might double check to make sure you’re not pregnant before you start treatment. Use birth control while taking Nerlynx (neratinib) and for at least 1 month after your last dose. If you’re a male taking Nerlynx (neratinib) and your partner is able to become pregnant, you should use birth control while you’re taking Nerlynx (neratinib) and for at least 3 months after your last dose. Let your provider know right away if you or your partner becomes pregnant during this time.

Nerlynx (neratinib) dosage forms

Typical dosing for Nerlynx (neratinib)

Each tablet contains 40 mg of neratinib.

The typical dose is 6 tablets (total of 240 mg of neratinib) taken at one time each day. Some people might start on a lower dose of Nerlynx (neratinib) first before the dose is slowly raised to 240 mg (see FAQs for more information).

Your dose might be different if you have liver problems or if you experience side effects.