Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Idhifa (Enasidenib). If you are concerned about side effects, discuss the risks and benefits of Idhifa (Enasidenib) with your doctor.

The following side effects have been reported by at least 1% of people taking Idhifa (Enasidenib). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• changed sense of taste
• decreased appetite
• Diarrhea
• fatigue
• nausea
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• difficulty breathing at rest or worsens when lying down
• Fever
• signs of Anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of clotting problems (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don’t stop bleeding)
• signs of infection (e.g., fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)

Stop taking the medication and seek immediate medical attention if any of the following occur:

• low levels of oxygen (hypoxia; changes in skin colour, confusion, fast heart rate, rapid breathing, shortness of breath, sweating, wheezing)
• symptoms of differentiation syndrome (e.g., fever, cough, shortness of breath, arm, leg or neck swelling, fast weight gain, dizziness, lightheadedness, bone pain)
• symptoms of tumour lysis syndrome (e.g., producing less urine, cloudy urine, kidney problems, muscle spasms, nausea, shortness of breath)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Idhifa (Enasidenib).

50 mg
Each pale yellow-to-yellow, oval tablet, debossed "ENA" on one side and "50" on the other side, contains 50 mg of Idhifa (Enasidenib) as Idhifa (Enasidenib) mesylate. Nonmedicinal ingredients: colloidal silicone dioxide, hydroxypropyl cellulose, hypromellose acetate succinate, iron oxide yellow, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polyvinyl alcohol, sodium lauryl sulfate, sodium starch glycolate, talc, and titanium dioxide.

100 mg
Each pale yellow-to-yellow, capsule-shaped tablet, debossed "ENA" on one side and "100" on the other side, contains 100 mg of Idhifa (Enasidenib) as Idhifa (Enasidenib) mesylate. Nonmedicinal ingredients: colloidal silicone dioxide, hydroxypropyl cellulose, hypromellose acetate succinate, iron oxide yellow, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polyvinyl alcohol, sodium lauryl sulfate, sodium starch glycolate, talc, and titanium dioxide.

Do not take Idhifa (Enasidenib) if you are allergic to Idhifa (Enasidenib) or any ingredients of the medication.

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Idhifa (Enasidenib).

Anemia: Idhifa (Enasidenib) may cause low levels of red blood cells. If you experience symptoms of reduced red blood cell count (anemia) such as shortness of breath, feeling unusually tired, or pale skin, contact your doctor as soon as possible. Your doctor will order routine blood tests to make sure potential problems are caught early.

Bleeding: Idhifa (Enasidenib) may cause a reduced number of platelets in the blood, which can make it difficult to stop cuts from bleeding. If you notice any signs of bleeding, such as frequent nosebleeds, unexplained bruising, or black and tarry stools, notify your doctor as soon as possible. Your doctor will order routine blood tests to make sure potential problems are caught early.

Birth control: Women of childbearing age who are taking Idhifa (Enasidenib) or whose male partners are taking Idhifa (Enasidenib) should use an effective method of birth control such as condoms during treatment and for at least 8 weeks after stopping the medication. If you become pregnant while taking Idhifa (Enasidenib), contact your doctor immediately.

White blood cells: As well as preventing cancer cells from forming, Idhifa (Enasidenib) can reduce the number of cells that fight infection in the body (white blood cells). If possible, avoid contact with people with contagious infections. Tell your doctor immediately if you notice signs of an infection, such as fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness. Your doctor will do blood tests regularly to monitor the number of specific types of blood cells in your blood.

Early in treatment, Idhifa (Enasidenib) can also cause the body to produce too many white blood cells. When this happens, it is usually within 3 months of starting the medication. If you experience fever for no apparent reason, contact your doctor as soon as possible.

Differentiation syndrome: Differentiation syndrome occurs when there is a rapid overproduction of certain blood cells. This condition can be severe and even life-threatening. It may occur 10 days to 5 months after you start to take Idhifa (Enasidenib). If you experience symptoms of differentiation syndrome, such as unexplained fever, cough, shortness of breath, swelling of the arms or legs, or swelling around the neck, groin, or underarms, rapid weight gain or fluid retention, bone pain, dizziness or lightheadedness contact your doctor as soon as possible.

Liver function: Idhifa (Enasidenib) may cause a decrease in liver function. If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Tumour lysis syndrome: Idhifa (Enasidenib), like many other cancer medications, causes many cancer cells to be suddenly killed when treatment is first started. This can overwhelm the body with waste products from the cells. As a result, the body may not be able to keep up with getting rid of all the waste. When this happens, you may experience nausea, shortness of breath, cloudy urine, or joint pain. This is called tumour lysis syndrome. Your doctor may prescribe some medications to help your body get rid of the waste products. Make sure you understand how to use these medications and report any of these signs or symptoms to your doctor immediately.

Pregnancy: Idhifa (Enasidenib) should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking Idhifa (Enasidenib), contact your doctor immediately.

Breast-feeding: It is not known if Idhifa (Enasidenib) passes into breast milk. If you are a breast-feeding mother and are taking Idhifa (Enasidenib), it may affect your baby. Women should avoid breast-feeding while taking Idhifa (Enasidenib) and for 8 weeks after the last dose of the medication.

Children: The safety and effectiveness of using Idhifa (Enasidenib) have not been established for children.