Rezdiffra (resmetirom) is a prescription drug used to treat certain types of nonalcoholic steatohepatitis (NASH). Rezdiffra can cause side effects that range from mild to serious, such as diarrhea and nausea.

Specifically, Rezdiffra is used to treat a type of nonalcoholic fatty liver disease called nonalcoholic steatohepatitis (NASH) in adults with moderate to advanced liver fibrosis.

Note: Rezdiffra is not used in people with liver cirrhosis.

Rezdiffra comes as a tablet you swallow. It contains the active ingredient resmetirom.

Keep reading to learn about common, mild, and serious side effects Rezdiffra can cause. And for a detailed overview of the drug, check out this in-depth Rezdiffra article.

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

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

Mild side effects have been reported with Rezdiffra. 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 Rezdiffra treatment unless your doctor recommends it.

Rezdiffra 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.

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

If you develop serious side effects while taking Rezdiffra, 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.

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 Rezdiffra, visit MedWatch.

ALLERGIC REACTION

For some people, Rezdiffra can cause an allergic reaction.

In general, symptoms of allergic reaction can be mild or serious.

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 continue Rezdiffra treatment.

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 Rezdiffra, they may have you switch to a different treatment.

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

Dizziness

Dizziness was a common side effect reported in studies of Rezdiffra. You may experience dizziness when you first begin treatment with Rezdiffra. In most cases, this side effect is mild and should ease as you continue treatment.

What might help

If you have dizziness that doesn’t go away or is bothersome, talk with your doctor. They may suggest taking Rezdiffra in the evening so dizziness doesn’t affect your daily activities. You should not drive or perform tasks that require alertness until you know how this medication affects you.

Talk with your doctor if you’re wondering how long this side effect may last.

Gallbladder problems

Treatment with Rezdiffra can cause problems with your gallbladder, including gallstones, cholecystitis, and cholelithiasis.

Gallbladder problems were a serious side effect reported in the drug’s studies and can cause symptoms such as:

  • frequent or severe abdominal pain
  • fever
  • jaundice (yellowing of the skin or the whites of the eyes)
  • pale stools
  • nausea and vomiting

What might help

If you experience symptoms of gallbladder problems with Rezdiffra, call your doctor. They’ll order tests to check your gallbladder and may temporarily or permanently stop your Rezdiffra treatment if needed. They’ll also discuss treatment options if you have gallstones or other gallbladder problems.

Talk with your doctor if you have questions about this side effect of Rezdiffra.

Keeping track of side effects

During your Rezdiffra 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 a new drug or 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 Rezdiffra affects you. They can then use this information to adjust your treatment plan if needed.

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

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

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.