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Generic name: neratinibne-RA-ti-nib ]
Drug classes: EGFR inhibitors, HER2 inhibitors

Medically reviewed by Philip Thornton, DipPharm. Last updated on Aug 22, 2023.

What is Nerlynx?

Nerlynx is a cancer medicine that interferes with the growth and spread of cancer cells in the body.

Nerlynx is used alone or with other medicines to treat early-stage HER2-positive breast cancer. Nerlynx is also used to treat HER2-positive breast cancer that is advanced or has spread to other parts of the body (metastatic).

Nerlynx is used for breast cancer only if your tumor tests positive for a protein called human epidermal growth factor receptor 2 (HER2). HER2 protein can speed the growth of cancer cells.

Nerlynx is usually given after you have been treated with another medicine called trastuzumab (Herceptin).


Nerlynx can cause severe diarrhea, which can be life-threatening if it leads to dehydration. You may be given anti-diarrhea medications for the first 2 months of treatment with Nerlynx.

Call your doctor if you are sick with severe diarrhea, or you also have weakness, dizziness, or a fever.

Before taking this medicine

To make sure Nerlynx is safe for you, tell your doctor if you have ever had:

You may need to have a negative pregnancy test before starting this treatment.

Neratinib can harm an unborn baby or cause birth defects if the mother or the father is using this medicine.

Do not breastfeed while using this medicine, and for at least 1 month after your last dose.

How should I take Nerlynx?

Take Nerlynx exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

The usual dose of Nerlynx is 6 tablets taken once daily. Take the medicine with food, at the same time each day.

You may need to take this medicine daily for up to one year. Nerlynx is sometimes taken daily in 21-day treatment cycles until the medicine stops working or until you have serious side effects.

Your doctor will determine how long to treat you with this medicine. Follow your doctor's dosing instructions very carefully.

Swallow the tablet whole and do not crush, chew, or break it.

Nerlynx can cause severe diarrhea, which can be life-threatening if it leads to dehydration. For the first 2 months of treatment with Nerlynx, you may need to take medication to prevent or quickly treat diarrhea.

Your doctor may recommend you have an anti-diarrhea medicine such as loperamide (Imodium) available at all times while you are taking Nerlynx. Take the anti-diarrhea medicine exactly as prescribed by your doctor.

To best control diarrhea, you may need to follow a special diet. Get familiar with the list of foods you should eat or avoid to help control diarrhea. You may also need to drink extra fluids to keep from getting dehydrated.

Tell your doctor if you have more than 2 bowel movements in 1 day.

Call your doctor if you are sick with severe diarrhea, or you also have weakness, dizziness, or a fever. You may need to stop taking this medicine for a short time.

You may need frequent blood tests.

Store at room temperature away from moisture and heat.

Dosing information

Usual Adult Dose for Breast Cancer -- Adjuvant:

240 mg orally once a day continuously for 1 year

NOTE: Antidiarrheal prophylaxis is recommended during the first 2 cycles (56 days) of therapy and should be initiated with the first dose. Titrate loperamide to 1 to 2 bowel movements per day.
-Weeks 1 and 2 (days 1 through 14): 4 mg orally 3 times a day
-Weeks 3 through 8 (days 15 through 56): 4 mg orally 2 times a day
-Weeks 9 through 52 (days 57 through 365): 4 mg as needed (not to exceed 16 mg per day)

Use: For the extended adjuvant treatment of adult patients with early stage HER2-overexpressed/amplified breast cancer (to follow adjuvant trastuzumab-based therapy)

What happens if I miss a dose?

Skip the missed dose and use your next dose at the regular time. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include severe diarrhea or vomiting, stomach pain, increased thirst, decreased urination, dark urine, dizziness, or hot and dry skin.

What to avoid

Grapefruit may interact with neratinib and lead to unwanted side effects. Avoid the use of grapefruit products.

Ask your doctor before using an antacid or stomach acid reducing medicine. Use only the type your doctor recommends.

Nerlynx side effects

Get emergency medical help if you have signs of an allergic reaction to Nerlynx: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

Your cancer treatments may be delayed or permanently discontinued if you have certain side effects.

Common Nerlynx side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Nerlynx?

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

If you also take an antacid: Wait at least 3 hours after taking the antacid before you take Nerlynx.

If you also take a stomach acid reducer: Take your Nerlynx dose 2 hours before or 10 hours after you take the other medicine (this includes cimetidine, famotidine, nizatidine, ranitidine, Axid, Pepcid, Tagamet, Zantac, and others).

You should not use certain stomach acid reducers, such as esomeprazole, lansoprazole, omeprazole, pantoprazole Nexium, Prevacid, Prilosec, Protonix, and others.

Other drugs may interact with neratinib, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Popular FAQ

Tucatinib (Tukysa) is used in the treatment of more advanced or metastatic HER2+ breast cancer or HER2+ colorectal cancer, while Neratinib (Nerlynx) is used in the treatment of both early-stage and advanced or metastatic HER2+ breast cancer, but is not approved for use in colorectal cancer. Continue reading

Diarrhea can start as soon as you start taking Nerlynx – 93% of women experienced diarrhea within the first month of treatment (average time to the onset of diarrhea was 8 days) in trials that did not require anti-diarrheal medication to be taken at the same time. However, the risk of diarrhea developing is greatly reduced in those who take loperamide, an antidiarrheal medication, at the same time as Nerlynx. Continue reading

Nerlynx (neratinib) is not a chemo drug it is a type of targeted treatment that works by irreversibly binding to and inhibiting specific receptors on the surface of cancer cells called HER2, HER4, and EGFR receptors, which receive signals that tell cancer to grow and spread. Continue reading

Although there is no direct interaction between alcohol and Nerlynx, you should not drink excessive quantities of alcohol while you are taking Nerlynx, because it may increase the risk of side effects such as diarrhea, dehydration, dizziness, and liver problems; as well as increase your cancer risk. It is OK to have a glass of alcohol every now and then while taking Nerlynx. Continue reading

Nerlynx is taken for up to a year when it is used to treat early-stage HER2-positive breast cancer, unless unacceptable toxicity or disease progression occurs. When Nerlynx is given to treat advanced-stage or metastatic HER2-positive breast cancer, it is taken for as long as you are getting benefits from the drug (for example your cancer has not got worse while you are taking Nerlynx) and you are tolerating it okay with no unacceptable side effects. Continue reading

Hair loss has not been reported as a side effect of Nerlynx. Hair loss is also not an anticipated side effect of Nerlynx because of the targeted way that it works, so if hair loss were to occur, it is probably due to other causes. Continue reading

Nerlynx is a type of targeted treatment that works by irreversibly binding to and inhibiting specific receptors on the surface of cancer cells called HER2, HER4, and EGFR receptors. These receptors receive signals that tell cancer to grow and spread. By inhibiting HER2 and EGFR receptors, Nerlynx prevents HER2 positive breast cancer cells from growing and multiplying. Continue reading

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Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Nerlynx only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.