Nerlynx side effects: What you should know

Nerlynx (neratinib) is a brand-name oral tablet that’s prescribed for certain types of breast cancer in adults. As with other drugs, Nerlynx can cause side effects, such as nausea, diarrhea, and fatigue.
More common side effects of Nerlynx
Nerlynx can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.
These are just a few of the more common side effects reported by people who took Nerlynx in clinical trials:
clinical trials
fatigue
fatigue
nausea and vomiting
nausea and vomiting
muscle spasms
muscle spasms
skin rash
skin rash
mild diarrhea*
* For more information about this side effect, see the “Side effect specifics” section.
Mild side effects of Nerlynx
Mild side effects can occur with Nerlynx use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Nerlynx’s prescribing information.
prescribing information
Mild side effects that have been reported with Nerlynx include:
fatigue
nausea and vomiting
muscle spasms
skin rash
stomatitis (mouth sores)
stomatitis
back pain
decreased appetite
abdominal pain
dizziness
mild diarrhea*
These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.
Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you develop a side effect while taking Nerlynx and want to tell the FDA about it, visit MedWatch.
MedWatch
* For more information about this side effect, see the “Side effect specifics” section.
Serious side effects of Nerlynx
Nerlynx may cause serious side effects. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Nerlynx’s prescribing information.
prescribing information
If you develop serious side effects while taking Nerlynx, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.
Serious side effects that have been reported and their symptoms include:
kidney failure, which may include symptoms such as: swelling of the legs and feetmetallic taste in the mouthconfusionitchy skin
kidney failure
swelling of the legs and feet
metallic taste in the mouth
metallic taste in the mouth
confusion
itchy skin
liver problems*
liver problems
severe diarrhea*
severe diarrhea
* For more information about this side effect, see the “Side effect specifics” section.
For some people, Nerlynx can cause an allergic reaction. But this side effect wasn’t reported in the drug’s clinical trials.
allergic reaction
clinical trials
In general, symptoms of allergic reaction can be mild or serious.
Ways to manage
For mild allergic reaction symptoms, such as a mild rash, call your doctor right away. They may recommend treatments to help manage your symptoms. They’ll also let you know whether you should keep taking the medication.
For severe allergic reaction symptoms, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms require immediate medical care because they can become life threatening. If you’ve had a serious allergic reaction to Nerlynx, your doctor may recommend taking a different medication instead.
FAQ about the side effects of Nerlynx
Nerlynx may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.
Nerlynx, anastrozole (Arimidex), and Herceptin are different types of breast cancer drugs. Nerlynx is an oral tablet that belongs to a class of drugs called kinase inhibitors. Anastrozole is also an oral tablet, and it belongs to the aromatase inhibitor drug class. Herceptin is given by intravenous (IV) infusion and belongs to the monoclonal antibody drug class. Some side effects of these drugs are similar, but some are different.
Arimidex
Herceptin
breast cancer drugs
intravenous (IV) infusion
Nerlynx, anastrozole, and Herceptin commonly cause mild side effects such as fatigue, diarrhea, dizziness, nausea, and vomiting. Nerlynx may also cause mouth sores, weight loss, indigestion, and abdominal pain. Anastrozole can cause edema (fluid buildup), weight gain, and hot flashes. Injection site reactions are possible with Herceptin, as well as shortness of breath, cough, and an increased risk of infection.
indigestion
edema
Injection site reactions
infection
Herceptin can cause serious side effects, such as blood disorders, heart problems, nerve damage, and kidney problems. Similar to Herceptin, anastrozole can cause heart problems. Anastrozole can also cause liver problems and weakened bones. Serious side effects of Nerlynx include diarrhea and liver problems.
blood disorders
liver problems
Talk with your doctor if you have questions about how the side effects of Nerlynx, anastrozole, and Herceptin compare. To learn more about the side effects of Nerlynx, see the “Mild side effects of Nerlynx” and “Serious side effects of Nerlynx” sections. For details about Herceptin’s side effects, you can view this article.
this article
No, hair loss wasn’t reported as a side effect in clinical trials of Nerlynx.
hair loss
clinical trials
Nerlynx belongs to a class of drugs called kinase inhibitors. Hair loss is most commonly associated with chemotherapy drugs that are used for breast cancer treatment, such as paclitaxel and docetaxel (Taxotere).
chemotherapy drugs
breast cancer treatment
Talk with your doctor if you have questions about hair loss during treatment with Nerlynx.
Side effect specifics
Learn more about some of the side effects that Nerlynx may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Nerlynx.
prescribing information
Nerlynx can cause changes in the levels of certain liver enzymes, called aspartate aminotransferase (AST) and alanine aminotransferase (ALT). These changes were commonly reported in clinical trials of Nerlynx. Elevated liver enzymes can be a sign of liver damage.
aspartate aminotransferase (AST)
alanine aminotransferase (ALT)
clinical trials
Elevated liver enzymes
sign of liver damage
Symptoms of liver damage may include:
pain or tenderness in the upper abdomen
skin rash
fever
nausea and vomiting
jaundice (yellowing of the skin or the whites of your eyes)
jaundice
If you have any symptoms of liver damage, call your doctor right away.
Your doctor will order a blood test called a liver function test to measure your liver enzyme levels. This test helps your doctor check your liver health. They’ll continue to do these tests every month during the first 3 months of Nerlynx treatment and then every 3 months afterward. If your blood test shows signs of severe liver damage, your doctor may recommend that you stop taking Nerlynx.
liver function test
Diarrhea was a common side effect reported in clinical trials of Nerlynx. Most people experienced diarrhea in the first month of treatment, which typically lasted about a week. In some cases, diarrhea was severe and led to serious complications. These included low blood pressure, dehydration, and kidney failure.
clinical trials
low blood pressure
kidney failure
Symptoms of severe diarrhea may include:
not being able to control bowel movements
having seven or more bowel movements per day
diarrhea that affects your daily activities
To help prevent diarrhea, your doctor may start your treatment with a low dose of Nerlynx and slowly increase it over 2 weeks. They may also recommend you take loperamide (Imodium) at the start of your treatment to help prevent diarrhea.
Imodium
If you develop diarrhea while taking Nerlynx, your doctor may recommend you drink lots of fluids and electrolytes as well as take an additional antidiarrheal medication. If your diarrhea is severe, your doctor may pause or permanently stop treatment with Nerlynx.
electrolytes
antidiarrheal medication
Tell your doctor if you have diarrhea that doesn’t go away or if you have more than two bowel movements per day. If you experience severe diarrhea or a fever with symptoms of dehydration, call your doctor right away. Symptoms of dehydration may include feeling dizzy or weak or having a dry mouth.
Precautions for Nerlynx
Below is important information you should consider before taking Nerlynx.
Before taking Nerlynx, discuss your health history with your doctor. Nerlynx may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:
liver problems
previous allergic reaction to Nerlynx or a similar drug
pregnancy
breastfeeding
Disclaimer: Medical News Today 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.