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Generic Name: neratinib (ne RA ti nib)
Brand Names: Nerlynx

Medically reviewed on Nov 1, 2018

What is Nerlynx?

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

Nerlynx is used to treat a certain type of early-stage breast cancer. It is used for this condition 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).

Important information

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

You should not use Nerlynx if you are allergic to neratinib.

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

  • liver disease.

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

Nerlynx can harm an unborn baby. Use effective birth control to prevent pregnancy while you are using this medicine, whether you are a man or a woman. Neratinib use by either parent may cause birth defects.

If you are a woman, keep using birth control for at least 1 month after your last dose of Nerlynx. If you are a man, keep using birth control for at least 3 months after your last dose. Tell your doctor right away if a pregnancy occurs while either the mother or the father is using neratinib.

It is not known whether neratinib passes into breast milk or if it could harm a nursing baby. You should not breast-feed 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. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Take the medicine with food, at the same time each day.

The usual dose is 6 tablets taken once daily for 1 year. Follow your doctor's dosing instructions very carefully.

Do not crush, chew, or break a Nerlynx tablet. Swallow the tablet whole.

Nerlynx can cause severe diarrhea, which can be life-threatening if it leads to dehydration. For the first 2 months of treatment, 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 as directed on the label, or 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.

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.

While using Nerlynx, you may need frequent blood tests.

Drink plenty of liquids while you are taking this medicine.

Store at room temperature away from moisture and heat.

Nerlynx dosing information

Usual Adult Dose for Breast Cancer -- Adjuvant:

240 mg orally once a day with food, continuously for 1 year

-Instruct patients to initiate antidiarrheal prophylaxis with loperamide along with the first dose of neratinib, and to continue using loperamide during the first 2 treatment cycles (56 days); consult the manufacturer product information for loperamide dosing recommendations.
-Advise patients to use additional antidiarrheal agents and/or make dietary changes as needed.

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?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

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 should I avoid while taking Nerlynx?

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

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

Nerlynx side effects

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

Call your doctor at once if you have:

  • more than 2 bowel movements in 1 day;

  • severe or ongoing diarrhea;

  • pain or burning when you urinate; or

  • liver problems - right-sided upper stomach pain, vomiting, tiredness, fever, itching, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

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

Common Nerlynx side effects may include:

  • diarrhea;

  • nausea, vomiting, stomach pain, bloating;

  • upset stomach, loss of appetite;

  • feeling tired;

  • rash, dry skin, problems with your fingernails or toenails;

  • dry mouth, mouth sores;

  • muscle spasms; or

  • weight loss.

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.

Tell your doctor about all your current medicines and any you start or stop using, especially:

  • a stomach acid reducer - such as Nexium, Prevacid, Prilosec, Tagamet, Zantac, and others.

This list is not complete. Other drugs may interact with neratinib, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

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.