Neratinib Side Effects

Medically reviewed by Philip Thornton, DipPharm. Last updated on Jul 18, 2024.

Applies to neratinib: oral tablet.

Precautions

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. If you are a woman who can get pregnant, your doctor may do tests to make sure you are not pregnant before starting treatment. Use an effective form of birth control to keep from getting pregnant during treatment with this medicine and for at least 1 month after your last dose. Male patients who have female partners should use effective birth control during treatment with this medicine and for 3 months after the last dose. If you think you have become pregnant while using this medicine, tell your doctor right away.

Check with your doctor right away if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, vomiting, or yellow eyes or skin. These could be symptoms of a serious liver problem.

Neratinib may cause severe diarrhea, which may lead to serious complications, including dehydration, low blood pressure (hypotension), or kidney failure. Your doctor will give you medicines to help prevent diarrhea during treatment with this medicine. If you have any questions about this or if diarrhea continues, or gets worse, check with your doctor.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (eg, St. John's wort) or vitamin supplements.

Serious side effects of neratinib

Along with its needed effects, neratinib may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking neratinib:

Other side effects of neratinib

Some side effects of neratinib may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to neratinib: oral tablet.

General adverse events

The most common adverse reactions (more than 5%) were diarrhea, nausea, abdominal pain, fatigue, vomiting, rash, stomatitis, decreased appetite, muscle spasms, dyspepsia, increased AST or ALT, nail disorder, dry skin, abdominal distention, decreased weight, and urinary tract infection.^[Ref]

Gastrointestinal

• Very common (10% or more): Diarrhea (95%), nausea (43%), abdominal pain (36%), vomiting (26%), stomatitis (14%), dyspepsia (10%)
• Common (1% to 10%): Abdominal distention, dry mouth^[Ref]

Other

• Very common (10% or more): Fatigue (27%)^[Ref]

Dermatologic

• Very common (10% or more): Rash (18%)
• Common (1% to 10%): Nail disorder, rash, skin fissures^[Ref]

Metabolic

• Very common (10% or more): Decreased appetite (12%)
• Common (1% to 10%): Decreased weight, dehydration^[Ref]

Musculoskeletal

• Very common (10% or more): Muscle spasms (11%)^[Ref]

Genitourinary

• Common (1% to 10%): Urinary tract infection^[Ref]

Hepatic

• Common (1% to 10%): Increased ALT, increased AST^[Ref]

Respiratory

• Common (1% to 10%): Epistaxis^[Ref]

Cardiovascular

• Frequency not reported: Hypotension^[Ref]

Renal

• Frequency not reported: Renal failure^[Ref]

See also:

Frequently asked questions

• What’s the difference between tucatinib and neratinib?
• When does diarrhea start when taking Nerlynx?
• Is Nerlynx (neratinib) a chemo drug?
• Can you drink alcohol with Nerlynx?
• How long do you take Nerlynx for?
• Does Nerlynx cause hair loss?
• How does Nerlynx (neratinib) work?
• How do you take Nerlynx?

Further information

Neratinib side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer