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INREBIC® (fedratinib) is a prescription medicine used to treat adults with certain types of myelofibrosis (MF). It is not known if INREBIC is safe and effective in children.

Understand Side Effects

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On this page:

    What’s the most important information to know about side effects?

    It’s important to understand the possible side effects of treatment. Talk to your doctor about any side effects that you may experience.

    patient and caregiver

     

    INREBIC may cause serious side effects, such as encephalopathy (including Wernicke’s encephalopathy). A serious and sometimes fatal neurological problem called encephalopathy (including Wernicke’s encephalopathy) has happened in some people who take INREBIC.

    Wernicke’s encephalopathy is a neurologic emergency that can happen if you do not have enough vitamin B1 (thiamine) in your body. Your healthcare provider will do a blood test to check your vitamin B1 level before starting and during treatment with INREBIC.

    Your healthcare provider may tell you to stop taking INREBIC and take a B1 vitamin if you develop side effects during treatment with INREBIC.

    Call your healthcare provider right away if you develop diarrhea, nausea, or vomiting that does not respond to treatment.

     

    Get emergency medical help right away if you develop the following:

    confusion, memory problems, or drowsiness

    Confusion, memory problems, or drowsiness

    problems with balance and movement

    Problems with balance and movement, such as difficulty walking

    eye problems

    Eye problems, such as double or blurred vision or abnormal eye movements

    Call your healthcare provider if you experience rapid weight loss or weight loss that does not get better with treatment.

    INREBIC can cause serious side effects, including:

    Low blood cell counts

    INREBIC may cause low red blood cell counts (anemia) and low platelet counts (thrombocytopenia) in some people. You may need a blood transfusion if your blood counts drop too low. Your healthcare provider will do blood tests to check your blood counts before you start and during treatment with INREBIC. Tell your healthcare provider if you develop any bleeding or bruising during treatment with INREBIC.

     

    Nausea, vomiting, and diarrhea

    Your healthcare provider may give you certain medicines to help treat your nausea, vomiting, and diarrhea. Call your healthcare provider or get emergency medical help right away if you have nausea, vomiting, or diarrhea that does not get better with treatment.

     

    Liver problems

    Your healthcare provider will do blood tests to check your liver function before starting and during treatment with INREBIC.

     

    Amylase and lipase increases

    You may have changes in your blood amylase or lipase levels that may indicate a problem with your pancreas. Your healthcare provider will do blood tests to check your amylase or lipase levels before starting and during treatment with INREBIC.

    The most common side effects of INREBIC include:

    • Diarrhea
    • Nausea
    • Low red blood cell counts (anemia)
    • Vomiting

     

    These are not all the possible side effects of INREBIC. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

    Talk to your doctor or pharmacist about possible side effects.

     

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    Indication

    What is INREBIC® (fedratinib)?

    INREBIC is a prescription medicine used to treat adults with certain types of myelofibrosis (MF). It is not known if INREBIC is safe and effective in children.


    Important Safety Information

    WARNING: ENCEPHALOPATHY INCLUDING WERNICKE’S

    What is the most important information I should know about INREBIC?
    INREBIC may cause serious side effects, including:

    • Encephalopathy (including Wernicke’s encephalopathy). A serious and sometimes fatal neurological problem called encephalopathy (including Wernicke’s encephalopathy) has happened in some people who take INREBIC.

       

      Wernicke’s encephalopathy is a neurologic emergency that can happen if you do not have enough vitamin B1 (thiamine) in your body. Your healthcare provider will do a blood test to check your vitamin B1 level before starting and during treatment with INREBIC. Your healthcare provider may tell you to stop taking INREBIC and take a vitamin B1 supplement if you develop side effects during treatment with INREBIC.

       

      Call your healthcare provider right away if you develop diarrhea, nausea, or vomiting that does not respond to treatment.

       

      Get emergency medical help right away if you develop the following:

      • confusion, memory problems, or drowsiness
      • problems with balance and movement, such as difficulty walking
      • eye problems, such as double or blurred vision or abnormal eye movements

       

      Call your healthcare provider if you experience rapid weight loss or weight loss that does not get better with treatment.

       

    Before taking INREBIC, tell your healthcare provider about all your medical conditions, including if you:

    • have low red blood cell or platelet counts
    • have or have had liver problems
    • have or have had kidney problems
    • are breastfeeding or plan to breastfeed. It is not known if INREBIC passes into your breast milk. You should not breastfeed during treatment with INREBIC and for at least 1 month after your last dose. Talk to your healthcare provider about the best way to feed your baby during treatment with INREBIC.

     

    Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

     

    INREBIC and other medicines may affect each other causing unwanted side effects. Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine.

     

    How should I take INREBIC?

     

    What are the possible side effects of INREBIC?
    INREBIC can cause serious side effects, including:

     

    The most common side effects of INREBIC include:

     

    These are not all of the possible side effects of INREBIC.

     

    Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

     

    Please see full Prescribing Information, including Boxed WARNING and Medication Guide, for INREBIC.