Xtandi (enzalutamide) is a brand-name drug that’s prescribed for prostate cancer in some situations in adults. Xtandi comes as an oral capsule and an oral tablet and is typically taken once per day.

Xtandi is approved by the Food and Drug Administration (FDA) to treat prostate cancer in adults in the following situations:

  • the cancer is responding to treatments that lower testosterone levels and:
  • the cancer is resistant to treatments that lower testosterone levels

Xtandi belongs to a drug class called androgen receptor blockers. Xtandi isn’t available in a generic version.

Keep reading for specific information about the dosage of Xtandi, including its strengths and how to take the medication. For a comprehensive look at Xtandi, see this article.

Note: This article describes typical dosages for Xtandi provided by the drug’s manufacturer. When taking Xtandi, always follow the dosage prescribed by your doctor.

Below is information about Xtandi’s forms, strengths, and dosages.

Xtandi forms

Xtandi comes as an oral tablet and an oral capsule.

Xtandi strengths

Xtandi oral capsule comes in one strength of 40 milligrams (mg).

Xtandi oral tablet comes in two strengths: 40 mg and 80 mg.

Typical dosages

Your doctor will ultimately prescribe the smallest dosage that provides the desired effect.

The following information describes dosages that are commonly prescribed. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Dosage for prostate cancer

Doctors may prescribe Xtandi to treat prostate cancer. The drug may be taken with other medications to manage your cancer.

If your doctor prescribes Xtandi for your prostate cancer, your dose will likely be 160 mg. Typically, you’ll take this once per day.

For more information about your specific dosage, talk with your doctor.

Long-term treatment

Xtandi is meant to be a long-term treatment. If you and your doctor determine that Xtandi is safe and effective for you, you’ll likely take it long term.

Before you start taking Xtandi, your doctor will discuss your treatment plan with you.

The Xtandi dosage your doctor prescribes will depend on several factors. These include:

  • other medications you take
  • side effects you may have with Xtandi

Other medical conditions you have can also affect your Xtandi dosage.

Dosage adjustments

Your doctor may need to adjust your dosage if you take certain medications, such as strong CYP2C8* inhibitors and CYP3A4* inducers. Examples of these drugs are gemfibrozil (Lopid) and rifampin (Rimactane). These drugs can affect the level of Xtandi in your body. To find out what other drugs may interact with Xtandi, see the “Interactions” section of this article.

Your doctor may also need to adjust your dosage if you have any side effects from taking Xtandi. To learn about Xtandi’s side effects, see this article.

Be sure to tell your doctor about all medications you take and any health conditions you may have.

* CYP2C8 and CYP3A4 are enzymes (a type of protein) in your liver that break down medications.

Xtandi is available as capsules and tablets that you swallow whole. Do not divide, crush, chew, or place the capsule or tablet in water. You should also not dissolve or open the capsules. You can take your dose with or without food.

It may be helpful to take Xtandi around the same time of day. This helps maintain a steady level of the drug in your body so Xtandi can work effectively.

If you have trouble swallowing Xtandi capsules or tablets, see this article for tips on how to take this form of medication. You can also talk with your doctor or pharmacist.

If you have questions about how to use Xtandi, talk with your doctor or pharmacist.

ACCESSIBLE DRUG LABELS AND CONTAINERS

Some pharmacies offer labels with large print, braille, or a code you scan with a smartphone to convert text to speech. If your local pharmacy doesn’t have these options, your doctor or pharmacist might be able to recommend a pharmacy that does.

If you’re having trouble opening medication bottles, ask your pharmacist about putting Xtandi in an easy-open container. They also may recommend tools that can make it easier to open bottles.

If you miss a dose of Xtandi, take it as soon as you remember. If you don’t remember until the following day, skip the missed dose. Then take your next dose at the usual time. Do not take two doses to make up for the missed one. If you’re not sure whether you should take a missed dose or skip it, talk with your doctor or pharmacist.

To help make sure that you don’t miss a dose, try using a medication reminder. This can include setting an alarm or putting a note where you’ll see it, such as on your bathroom mirror or bedside table. You could also download a reminder app on your phone.

It’s important that you don’t take more Xtandi than your doctor prescribes. For some medications, taking more than the recommended amount may lead to harmful effects or overdose. To learn about Xtandi’s side effects, see this article.

Effects of an overdose

It’s possible for an overdose of Xtandi to cause seizures. For more information about this, talk with your doctor.

If you take more than the recommended amount of Xtandi

Call your doctor right away if you believe you’ve taken too much Xtandi. Another option is to call America’s Poison Centers at 800-222-1222 or use its online tool. If you have severe symptoms, immediately call 911 or your local emergency number, or go to the nearest emergency room.

Below are some frequently asked questions about Xtandi and dosage.

Is there a best time of day to take Xtandi?

No, the manufacturer of Xtandi doesn’t recommend a specific time of day to take Xtandi. But it may be helpful to take your dose at about the same time each day. This helps keep a consistent amount of the drug in your body, which can help Xtandi work well.

To make sure you’re taking Xtandi at about the same time each day, it may be helpful to set a reminder on your phone or leave a note for yourself.

Is the dosage of Xtandi similar to the dosage of Erleada?

Yes, the forms and how often you take each drug are similar. Both Xtandi and Erleada (apalutamide) are available as oral tablets taken once daily. Xtandi also comes as an oral capsule.

The dose in milligrams (mg) for each drug differs because they have different active ingredients. Your doctor will prescribe the drug and the dosage that’s right for you.

To learn more about how these drugs compare, talk with your doctor.

How long does it take for Xtandi to start working?

Xtandi starts to work after your first dose. Because of how the drug works, you likely won’t feel the drug working in your body. But your doctor will monitor you during treatment to check whether the drug is working to treat your condition.

Talk with your doctor if you have questions about what to expect with Xtandi treatment.

The dosages in this article are typical dosages provided by the drug’s manufacturer. If your doctor recommends Xtandi for you, they will prescribe the dosage that’s right for you. Always follow the dosage that your doctor prescribes.

As with any drug, never change your dosage of Xtandi without your doctor’s recommendation. If you have questions about the dosage of Xtandi that’s best for you, talk with your doctor.

Besides learning about dosage, you may want other information about Xtandi. These additional articles might be helpful:

Disclaimer: Medical News Today 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.