Class Name(s):

• 10:00 Antineoplastic Agents

Pronunciation:

• (en'' za loo' ta mide)

Brand Name(s):

• Xtandi^®

WHY is this medicine prescribed?

Enzalutamide is used to treat certain types of prostate cancer. Enzalutamide is in a class of medications called androgen receptor inhibitors. It works by blocking the effects of androgen (a male reproductive hormone) to stop the growth and spread of cancer cells.

HOW should this medicine be used?

Enzalutamide comes as a tablet or a capsule to take by mouth. Take with or without food once a day. Take enzalutamide at around the same time every day.

Take enzalutamide exactly as directed. Ask your doctor or pharmacist to explain any part you do not understand. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets or capsules whole with water; do not crush, chew, divide, dissolve, or open them. Take tablets and capsules with enough water to make sure that they are swallowed whole, as they can get stuck in your throat or cause choking or gagging.

Your doctor may tell you to stop taking enzalutamide for a short time or decrease your dose if you experience serious side effects during your treatment. Be sure to talk to your doctor about how you are feeling during your treatment with enzalutamide.

If your doctor has prescribed another medication such as degarelix (Firmagon®), goserelin (Zoladex®), histrelin (Supprelin® LA, Vantas®), leuprolide (Eligard®, Lupron®, others), or triptorelin (Trelstar®, Triptodur®) to treat your prostate cancer, you will need to continue receiving this medication during your treatment with enzalutamide.

Continue to take enzalutamide even if you feel well. Do not stop taking enzalutamide without talking to your doctor.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Are there OTHER USES for this medication?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What SPECIAL PRECAUTIONS should I follow?

Before taking enzalutamide,

• tell your doctor and pharmacist if you are allergic to this drug, any part of this drug, or any other drugs, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take while taking enzalutamide. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• the following herbal product may interact with enzalutamide: St. John's wort. Be sure to let your doctor and pharmacist know that you are taking this medication before you start taking enzalutamide. Do not start this medication while taking enzalutamide without discussing with your healthcare provider.
• tell your doctor if you have problems swallowing, or if you have or have ever had seizures, a brain injury, a brain tumor, a brain arteriovenous malformation (abnormal connection between arteries and veins in the brain that forms before birth and may cause bleeding in the brain), broken bones, osteoporosis (a condition in which the bones become thin and weak and break easily), diabetes, high cholesterol levels, high blood pressure, heart disease, or have had a stroke or ministroke.
• you should know that enzalutamide is only for use in men. Women should not take this medication, especially if they are or may become pregnant or are breast-feeding. Women, especially those who are or who may become pregnant should not touch enzalutamide capsules. If taken by pregnant women, enzalutamide may harm the fetus. If a pregnant woman takes enzalutamide, she should call her doctor immediately.
• you should know that this medication may decrease fertility in men. However, you should not assume that your female partner cannot become pregnant. If your partner is pregnant, you must use a condom whenever you have sex during your treatment with enzalutamide and for 3 months after your final dose. If your partner is not pregnant but could become pregnant, you must use effective birth control whenever you have sex during your treatment and for 3 months after your final dose.
• if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking enzalutamide.
• you should know that enzalutamide may cause seizures. Do not drive a car or operate machinery until you know how this medication affects you.

What SPECIAL DIETARY instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do IF I FORGET to take a dose?

Take the missed dose as soon as you remember it. However, if you do not remember until the next day, skip the missed dose and continue your regular dosing schedule. Do not take more than one dose in one day and do not take a double dose to make up for a missed one.

What SIDE EFFECTS can this medicine cause?

Enzalutamide may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• unusual tiredness or weakness
• joint pain
• muscle pain, weakness, or stiffness
• fever, cough, sore throat, or other signs of infection
• weight loss
• loss of appetite
• headache
• dizziness
• burning, numbness, or tingling in the arms, hands, or feet
• decreased sense of touch or ability to feel sensation
• hot flashes
• difficulty falling asleep or staying asleep
• anxiety
• difficulty remembering, thinking, or paying attention
• diarrhea
• constipation
• itching or dry skin
• nosebleeds
• frequent urination
• taste changes

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

• loss of consciousness or seizures
• headache; confusion; or vision changes
• swelling of the face, tongue, lips, throat, arms, legs, hands, or feet
• chest pain or shortness of breath
• pain in the back, muscles, and/or legs; numbness or tingling in the buttocks or legs; or difficulty controlling urination or bowel movements
• falling
• broken bones or fractures
• breast enlargement in men
• pink or red urine

Enzalutamide may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at http://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

• seizures

What should I know about STORAGE and DISPOSAL of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location - one that is up and away and out of their sight and reachhttp://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website http://goo.gl/c4Rm4p for more information.

What OTHER INFORMATION should I know?

Keep all appointments with your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS^® Patient Medication Information™ Copyright, 2025. The American Society of Health-System Pharmacists^®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: April 15, 2025.