Lumakras (sotorasib) is a prescription oral tablet used to treat non-small cell lung cancer in certain adults. Lumakras can cause side effects that range from mild to serious. Examples include diarrhea and liver damage.

Some people may experience mild to serious side effects during Lumakras treatment. Examples of the drug’s commonly reported side effects include:

* To learn more about this side effect, see the “Side effects explained” section below.

Mild side effects have been reported with Lumakras. These include:

In most cases, these side effects should be temporary. And some may be easily managed. But if you have symptoms that are ongoing or bothersome, talk with your doctor or pharmacist. And do not stop taking Lumakras unless your doctor recommends it.

Lumakras may cause mild side effects other than those listed above. See the drug’s prescribing information for details.

* To learn more about this side effect, see the “Side effects explained” section below.

Serious side effects have been reported with Lumakras. These include:

If you develop serious side effects while taking Lumakras, 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.

* To learn more about this side effect, see the “Side effects explained” section below.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Lumakras, visit MedWatch.

Allergic reaction

For some people, Lumakras may cause an allergic reaction, but this side effect wasn’t reported in the drug’s studies.

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should keep taking Lumakras.

If you have symptoms of a severe allergic reaction, such as swelling or difficulty breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Lumakras, they may have you switch to a different treatment.

Learn more about some of the side effects Lumakras may cause.

Diarrhea

Mild diarrhea was a common side effect reported in studies of Lumakras, while severe diarrhea was less common.

With diarrhea, you may have watery, loose stools. In extreme cases, severe diarrhea may lead to dehydration or require hospital treatment.

What might help

If you have diarrhea during Lumakras treatment, talk with your doctor. They’ll likely advise you to stay hydrated by drinking liquids that contain electrolytes, such as Pedialyte or Gatorade. They may also recommend treatments such as loperamide (Imodium A-D) to relieve your symptoms.

If your diarrhea symptoms do not ease with treatment, contact your doctor right away. They may temporarily pause your Lumakras treatment until your symptoms improve. They can also tell you whether your symptoms are severe enough to seek hospital treatment.

Liver damage

High levels of liver enzymes (proteins) were common in studies of Lumakras. This side effect may be a sign of liver damage. More severe forms of liver damage, such as hepatitis, were less common in the drug’s studies.

Liver damage may cause symptoms such as:

What might help

Before starting Lumakras, your doctor will order blood tests to check how well your liver is working. They’ll repeat this from time to time during your Lumakras treatment. If you have a liver problem before starting this drug, your doctor will determine whether this drug is the best option for you.

If you have liver damage during Lumakras treatment, your doctor may have you temporarily pause or permanently stop taking this medication.

Lung problems

Lung problems were rare in studies of Lumakras but may include pneumonia, inflammation of the lungs, and interstitial lung disease (lung scarring).

Symptoms can vary depending on the specific lung problem but may include:

What might help

If you have symptoms of a lung problem during Lumakras treatment, talk with your doctor. They can help determine whether your symptoms are related to a side effect of Lumakras or non-small cell lung cancer.

If you have lung problems related to Lumakras treatment, your doctor may have you permanently stop taking the drug.

Keeping track of side effects

During your Lumakras treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you first start taking a new drug or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were taking when you had the side effect
  • how soon you had the side effect after starting that dose
  • what your symptoms were
  • how your symptoms affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

Sharing notes with your doctor will help them learn more about how Lumakras affects you. They can then use this information to adjust your treatment plan if needed.

Lumakras can sometimes cause harmful effects in people with certain conditions. This is known as a drug-condition interaction. Other factors may also affect whether this drug is a good treatment option for you.

Talk with your doctor about your health history before starting Lumakras. Be sure to tell them if any of the following factors apply to you:

  • lung problems (other than non-small cell lung cancer)
  • liver problems, such as liver failure
  • previous allergic reaction to Lumakras
  • pregnancy
  • breastfeeding
  • alcohol consumption

Disclaimer: Healthline 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.