Warning: Encephalopathy including Wernicke'sSerious and fatal encephalopathy, including Wernicke’s, has occurred in patients treated with fedratinib. Wernicke’s encephalopathy is a neurologic emergency. Assess thiamine levels in all patients prior to starting fedratinib, periodically during treatment, and as clinically indicated. Do not start fedratinib in patients with thiamine deficiency; replete thiamine prior to treatment initiation. If encephalopathy is suspected, immediately discontinue fedratinib and initiate parenteral thiamine. Monitor until symptoms resolve or improve and thiamine levels normalize .
Medically reviewed by Drugs.com. Last updated on Jan 17, 2020.
Commonly used brand name(s)
In the U.S.
Available Dosage Forms:
Therapeutic Class: Antineoplastic Agent
Uses for fedratinib
Fedratinib is used to treat intermediate-2 or high-risk myelofibrosis, including primary or secondary (post-polycythemia vera and post-essential thrombocythemia) myelofibrosis. Myelofibrosis is a life-threatening bone marrow problem which is manifested by the following symptoms: enlarged spleen (splenomegaly), severe itching, fever, night sweats, weight loss, bone pain, or unusual tiredness or weakness.
Fedratinib is available only with your doctor's prescription.
Before using fedratinib
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For fedratinib, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to fedratinib or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies have not been performed on the relationship of age to the effects of fedratinib in the pediatric population. Safety and efficacy have not been established.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of fedratinib in the elderly.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking fedratinib, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using fedratinib with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- St John's Wort
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of fedratinib. Make sure you tell your doctor if you have any other medical problems, especially:
- Anemia (low number of red blood cells) or
- Liver disease or
- Thrombocytopenia (low number of platelets)—Use with caution. May make these conditions worse.
- Kidney disease, moderate or severe—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
- Severe liver disease or
- Thiamine (Vitamin B1) deficiency—Should not be started in patients with this conditions.
Proper use of fedratinib
Take fedratinib only as directed by your doctor. Your dose depends on your blood tests and needs to be changed several times in order to find out what works best for you. Do not use more medicine, do not use it more often, and do not use it for a longer time than your doctor ordered.
Fedratinib comes with a Medication Guide. Read and follow the instructions carefully. Ask your doctor if you have any questions.
You may take fedratinib with or without food. However, taking fedratinib with a high fat meal may prevent nausea and vomiting.
Keep using fedratinib for as long as your doctor has told you to. Do not change your dose or stop taking fedratinib without first talking with your doctor.
Do not eat grapefruit or drink grapefruit juice while you are using fedratinib. Grapefruit and grapefruit juice may change the amount of fedratinib that is absorbed in the body.
The dose of fedratinib will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of fedratinib. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage form (capsules):
- For myelofibrosis:
- Adults—400 milligrams (mg) once a day, depending on your blood test results. Your doctor may adjust your dose as needed and tolerated.
- Children—Use and dose must be determined by your doctor.
- For myelofibrosis:
If you miss a dose of fedratinib, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Precautions while using fedratinib
It is very important that your doctor check your progress at regular visits to make sure fedratinib is working properly. Blood tests will be needed to check for unwanted effects.
Tell your doctor if you are using ruxolitinib (Jakafi®) before starting fedratinib. Using these medicines together may cause serious side effects.
Fedratinib may cause encephalopathy (brain disease), including Wernicke’s encephalopathy, which may be serious and life-threatening. Wernicke’s encephalopathy is caused by acute thiamine (Vitamin B1) deficiency. Check with your doctor right away if you have confusion, drowsiness, double vision, diarrhea, nausea, vomiting, problems with muscle control or coordination, shakiness and unsteady walk, trembling, trouble remembering, and weight loss (leading to malnutrition and lower thiamine levels).
Fedratinib will lower the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.
Fedratinib often causes diarrhea, nausea, and vomiting. However, it is very important that you continue to receive the medicine even if you begin to feel ill. Your doctor may give you a medicine to help prevent these side effects.
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 or vitamin supplements.
Fedratinib side effects
Along with its needed effects, a medicine 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:
- Black, tarry stools
- bleeding gums
- blood in the urine or stools
- lower back or side pain
- painful or difficult urination
- pale skin
- pinpoint red spots on the skin
- sore throat
- troubled breathing with exertion
- ulcers, sores, or white spots in the mouth
- unusual bleeding or bruising
- unusual tiredness or weakness
- Bladder pain
- cloudy urine
- difficult, burning, or painful urination
- frequent urge to urinate
- lower back or side pain
- shakiness and unsteady walk
- trouble remembering
- uncontrolled eye movements
- unsteadiness, trembling, or other problems with muscle control or coordination
Some side effects 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:
- Bone pain
- lack or loss of strength
- muscle spasms
- pain in the arms or legs
- weight gain
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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More about fedratinib
- Side Effects
- During Pregnancy
- Dosage Information
- Drug Interactions
- En Español
- Drug class: multikinase inhibitors
Other brands: Inrebic