Zydelig (idelalisib) is a prescription drug used to treat chronic lymphocytic leukemia (CLL). The drug comes as an oral tablet that’s typically taken twice per day.

Zydelig is prescribed to treat relapsed CLL in adults. It’s taken together with Rituxan (rituximab) in people who are able to take rituximab on its own.

Zydelig belongs to a group of drugs called kinase inhibitors and contains the active ingredient idelalisib. (An active ingredient is what makes a drug work.)

This article describes Zydelig’s dosage, as well as its strengths and how to take it. To learn more about Zydelig, see this in-depth article.

This section describes the usual dosage of Zydelig.

What is Zydelig’s form?

Zydelig comes as an oral tablet.

What strengths does Zydelig come in?

Zydelig comes in two strengths: 100 milligrams (mg) and 150 mg.

What’s the usual dosage of Zydelig?

The information below describes dosages that are commonly used or recommended. But be sure to take the dosage your doctor prescribes for you. They’ll determine the best dosage to fit your needs.

Dosage for CLL

The typical Zydelig dosage for adults with relapsed CLL is 150 mg taken twice per day. Zydelig is taken in combination with Rituxan (rituximab) treatment.*

You’ll likely take Zydelig until your condition worsens or you cannot tolerate the medication.

If you have questions about your dosage, talk with your doctor.

* Rituxan comes as a liquid solution given as an intravenous (IV) infusion (an injection into a vein given over time). You’ll receive Rituxan infusions from a healthcare professional in a clinic, doctor’s office, or hospital.

Is Zydelig used long term?

Yes, Zydelig is usually a long-term treatment. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely take it long term.

The dosage of Zydelig you’re prescribed may depend on several factors. These include:

  • side effects you may experience, such as liver problems, colitis, and severe diarrhea
  • other medications you take

Zydelig comes as an oral tablet. You can take it with or without food. Do not cut, crush, or chew Zydelig tablets. Swallow them whole. If you have trouble swallowing tablets, see this article for tips on how to take this form of medication.

For information on the expiration, storage, and disposal of Zydelig, talk with your doctor or pharmacist.

Accessible drug containers and labels

Some pharmacies provide medication labels that:

  • have large print
  • use braille
  • feature a code you can scan with a smartphone to change the text to audio

Your doctor or pharmacist may be able to recommend pharmacies that offer these accessibility features if your current pharmacy doesn’t.

Let your pharmacist know if you have trouble opening medication bottles. They may have tips to help, or they may be able to supply Zydelig in an easy-open container.

If you miss a dose of Zydelig, take it as soon as you remember. But if it’s been 6 hours or more since your missed dose, skip the missed dose and take your next scheduled dose at its usual time. If you’re not sure whether you should take a missed dose, talk with your doctor or pharmacist.

If you need help remembering to take your dose of Zydelig on time, try using a medication reminder. This can include setting an alarm or downloading a reminder app on your phone.

Do not take more Zydelig than your doctor prescribes, as this can lead to harmful effects.

What to do in case you take too much Zydelig

Call your doctor right away if you think you’ve taken too much Zydelig. You can also call 800-222-1222 to reach America’s Poison Centers or use its online resource. But if you have severe symptoms, immediately call 911 (or your local emergency number) or go to the nearest emergency room.

Below are answers to some commonly asked questions about Zydelig’s dosage.

Is Zydelig’s dosage similar to that of Venclexta?

No. Both Zydelig and Venclexta (venetoclax) are prescribed to treat CLL (and Venclexta is used to treat other types of cancer). Both drugs come as oral tablets, but they have different active ingredients. (An active ingredient is what makes a drug work.) And the dose in milligrams and dosing schedules for the two drugs differ.

Talk with your doctor to learn more about how these drugs compare. They’ll prescribe the best drug and dosage for treating your condition.

How long does it take for Zydelig to start working?

Zydelig starts to work after your first dose. But because of how it works, you likely won’t feel the drug working in your body. Your doctor will monitor you during treatment to be sure the drug is effectively treating your condition.

If you have other questions about what to expect from your Zydelig treatment, talk with your doctor.

The sections above describe the usual dosage provided by Zydelig’s manufacturer. If your doctor recommends this drug, they’ll prescribe the dosage that’s right for you.

Do not change your dosage of Zydelig without your doctor’s recommendation. Only take this drug exactly as prescribed. Talk with your doctor if you have questions or concerns about your current dosage. Examples of questions you may want to ask include:

  • Will a lower dosage of Zydelig still work to treat my condition?
  • Does my dosage of Zydelig need to change if I’m taking other medications?
  • How does Zydelig’s dosage compare with that of Gazyva (obinutuzumab)?

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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.