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Zydelig
Generic name: idelalisib
What is Zydelig?
Zydelig is a cancer medication that interferes with the growth and spread of cancer cells in the body.
Zydelig is used together with rituximab (Rituxan) to treat chronic lymphocytic leukemia, and certain types of lymphoma. It should not be used as the first medicine to treat anyone, and should not be used in combination with bendamustine and rituximab, or in combination with rituximab to treat people with follicular lymphoma, small lymphocytic lymphoma, and other slow growing non-Hodgkin lymphomas.
Zydelig is sometimes given after at least two other cancer treatments did not work or have stopped working.
Zydelig was approved by the US Food and Drug Administration (FDA) on an "accelerated" basis to treat lymphoma. In clinical studies, some people responded to this medicine, but further studies are needed.
How should I take Zydelig?
Zydelig is usually taken twice per day. Follow all directions on your prescription label and read all medication guides or instruction sheets.
You may take Zydelig with or without food.
Swallow the tablet whole and do not crush, chew, or break it.
You may have severe or life-threatening diarrhea while taking Zydelig. Tell your doctor at once if your daily bowel movements increase by 6 or more.
You may need frequent medical tests to be sure this medicine is not causing harmful effects. Your cancer treatments may be delayed based on the results.
Do not stop using Zydelig without your doctor's advice.
Store this medicine in the original container at room temperature, away from moisture and heat.
Warnings
Zydelig can cause serious harm to your liver, lungs, or intestines, and can cause serious infections. Some of these conditions may lead to fatal complications. Call your doctor right away if you have: upper stomach pain, easy bruising or bleeding, dark urine, yellowing of your skin or eyes, cough, wheezing, shortness of breath, fever, chills, worsening stomach pain, vomiting, or any signs of an infection.
You may have severe or life-threatening diarrhea while taking Zydelig. Tell your doctor at once if your daily bowel movements increase by 6 or more. Zydelig can also cause a perforation (a hole or tear) in your intestines. Call your doctor at once if you have diarrhea that is watery or bloody, if you have bloody or tarry stools, or if you cough up blood that looks like coffee grounds.
Before taking this medicine
You should not use Zydelig if you have had a serious allergic reaction to idelalisib, or if you have ever had a severe skin reaction called toxic epidermal necrolysis (TEN) to any medicine.
To make sure Zydelig is safe for you, tell your doctor if you have ever had:
- liver disease;
- lung disease;
- a perforation (a hole or tear) in your intestines; or
- an infection.
Idelalisib can harm an unborn baby if the mother or the father is using this medicine.
- If you are a woman, do not use Zydelig if you are pregnant. You may need to have a negative pregnancy test before starting this treatment. Use effective birth control to prevent pregnancy while you are using this medicine and for at least 1 month after your last dose.
- If you are a man, use effective birth control if your sex partner is able to get pregnant. Keep using birth control for at least 3 months after your last dose.
- Tell your doctor right away if a pregnancy occurs while either the mother or the father is using Zydelig.
Do not breastfeed while using this medicine, and for at least 1 month after your last dose.
It is not known if Zydelig is safe and effective in children.
Zydelig side effects
Get emergency medical help if you have signs of an allergic reaction to Zydelig (hives, difficult breathing or swallowing, cough, feeling dizzy or faint, a fast heartbeat, swelling in your face, lips, or tongue) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).
Seek medical treatment if you have a serious drug reaction that can affect many parts of your body. Symptoms may include: skin rash, fever, swollen glands, muscle aches, severe weakness, unusual bruising, or yellowing of your skin or eyes.
Zydelig can cause serious harm to your liver, lungs, or intestines, and can cause serious infections. You may have severe or life-threatening diarrhea, or a perforation (a hole or tear) in your intestines. Some of these conditions may lead to fatal complications.
Call your doctor at once if you have:
- severe diarrhea, increased number of stools per day;
- easy bruising, unusual bleeding, purple or red spots under your skin;
- intestinal problems - worsening stomach pain, fever, chills, vomiting;
- liver problems - upper stomach pain, loss of appetite, dark urine, jaundice (yellowing of the skin or eyes);
- lung problems - worsening cough, wheezing, cough with mucus, or shortness of breath;
- low white blood cell counts - fever, mouth sores, skin sores, sore throat;
- signs of infection - fever or any other signs of an infection.
Your cancer treatments may be delayed or permanently discontinued if you have certain side effects.
Common Zydelig side effects may include:
- nausea, stomach pain, diarrhea;
- fever, cough, lung problems;
- low white blood cells;
- abnormal liver function tests;
- rash; or
- feeling tired.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Dosing information
Usual Adult Dose of Zydelig for non-Hodgkin's Lymphoma:
150 mg orally 2 times a day until disease progression or unacceptable toxicity Comments: -This drug can be taken with or without food. -Tablets should be swallowed whole. -If the patient misses a dose within 6 hours of the time it is usually taken, the patient should take the missed dose as soon as possible and resume the normal dosing schedule. -If a patient misses a dose by more than 6 hours, the patient should not take the missed dose and simply resume the usual dosing schedule. Uses: -In combination with rituximab, for the treatment of patients with relapsed chronic lymphocytic leukemia (CLL) for whom rituximab alone would be considered appropriate therapy due to other co-morbidities. -The treatment of patients with relapsed follicular B-cell non-Hodgkin lymphoma (FL) who have received at least 2 prior systemic therapies. -The treatment of patients with relapsed small lymphocytic lymphoma (SLL) who have received at least 2 prior systemic therapies.
Usual Adult Dose of Zydelig for Chronic Lymphocytic Leukemia:
150 mg orally 2 times a day until disease progression or unacceptable toxicity Comments: -This drug can be taken with or without food. -Tablets should be swallowed whole. -If the patient misses a dose within 6 hours of the time it is usually taken, the patient should take the missed dose as soon as possible and resume the normal dosing schedule. -If a patient misses a dose by more than 6 hours, the patient should not take the missed dose and simply resume the usual dosing schedule. Uses: -In combination with rituximab, for the treatment of patients with relapsed chronic lymphocytic leukemia (CLL) for whom rituximab alone would be considered appropriate therapy due to other co-morbidities. -The treatment of patients with relapsed follicular B-cell non-Hodgkin lymphoma (FL) who have received at least 2 prior systemic therapies. -The treatment of patients with relapsed small lymphocytic lymphoma (SLL) who have received at least 2 prior systemic therapies.
Usual Adult Dose of Zydelig for Lymphoma:
150 mg orally 2 times a day until disease progression or unacceptable toxicity Comments: -This drug can be taken with or without food. -Tablets should be swallowed whole. -If the patient misses a dose within 6 hours of the time it is usually taken, the patient should take the missed dose as soon as possible and resume the normal dosing schedule. -If a patient misses a dose by more than 6 hours, the patient should not take the missed dose and simply resume the usual dosing schedule. Uses: -In combination with rituximab, for the treatment of patients with relapsed chronic lymphocytic leukemia (CLL) for whom rituximab alone would be considered appropriate therapy due to other co-morbidities. -The treatment of patients with relapsed follicular B-cell non-Hodgkin lymphoma (FL) who have received at least 2 prior systemic therapies. -The treatment of patients with relapsed small lymphocytic lymphoma (SLL) who have received at least 2 prior systemic therapies.
What happens if I miss a dose?
Take the medicine as soon as you can, but skip the missed dose if you are more than 6 hours late for the dose. Do not take two doses at one time.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
Follow your doctor's instructions about any restrictions on food, beverages, or activity.
What other drugs will affect Zydelig?
Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.
Other drugs may interact with idelalisib, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.
Common questions about Zydelig
What is Zydelig used for and how does it work?
Is Zydelig a chemotherapy drug?
Related medicines
Content is provided for education and is not medical advice. See our medical disclaimer. Source page medically reviewed by Philip Thornton, DipPharm on September 11, 2026.