Enzalutamide is used to treat prostate cancer that has spread to other parts of the body in men and who have been helped by certain medical and surgical treatments that decrease testosterone levels. It is also used to treat prostate cancer in men who have not been helped by certain medical and surgical treatments that decrease testosterone levels.

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.

Side Effects Of Enzalutamide

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

  • weakness
  • tiredness
  • joint pain
  • muscle weakness or stiffness
  • 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 the sensation
  • hot flashes
  • difficulty falling asleep or staying asleep
  • anxiety
  • difficulty remembering, thinking, or paying attention
  • diarrhea
  • constipation
  • itching
  • 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:

  • seizures
  • headache; confusion; or vision changes
  • swelling of the face, tongue, lips, throat, arms, legs, hands, or feet
  • fever, cough, sore throat, or other signs of infection
  • chest pain
  • shortness of breath
  • pain in the back, muscles, and/or legs
  • numbness or tingling in the buttocks or legs
  • difficulty controlling urination or bowel movements
  • difficulty breathing
  • falling
  • broken bones or fractures
  • hallucinating (seeing things or hearing voices that do not exist)
  • 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.

Warnings & Precautions

Before taking enzalutamide:

  • tell your doctor and pharmacist if you are allergic to enzalutamide, any other medications, or any of the ingredients in enzalutamide capsules. Ask your pharmacist or check the manufacturer’s information for the patient for a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take. Be sure to mention any of the following: anticoagulants (‘blood thinners’) such as warfarin (Coumadin, Jantoven), carbamazepine (Carbatrol, Equetro, Tegretol), cyclosporine (Gengraf, Neoral, Sandimmune), dihydroergotamine (D.H.E. 45, Migranal), efavirenz (Sustiva, in Atripla), ergotamine (in Migergot, in Cafergot), fentanyl (Abstral, Actiq, Duragesic, others), gemfibrozil (Lopid), itraconazole (Onmel, Sporanox), omeprazole (Prilosec), midazolam, phenobarbital, phenytoin (Dilantin, Phenytek), pimozide (Orap), quinidine (in Nuedexta), rifabutin (Mycobutin), rifampin (Rimactane, in Rifamate, in Rifater), rifapentine (Priftin), sirolimus (Rapamune), and tacrolimus (Prograf). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with enzalutamide, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
  • tell your doctor what herbal products you are taking, especially St. John’s wort.
  • tell your doctor if you have or have ever had seizures, a brain injury, a brain tumor, a brain arteriovenous malformation (an abnormal connection between arteries and veins in the brain that forms before birth and may cause bleeding in the brain), 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 a condom and another form of 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.

Enzalutamide Dosage

Enzalutamide comes as a capsule to take by mouth. It is usually taken with or without food once a day. Take enzalutamide at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take enzalutamide exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the capsules whole; do not chew, dissolve, or open them.

Do not allow other people to touch your capsules other than a caregiver. The capsules should especially not be handled by women who are pregnant or who can become pregnant.

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), or triptorelin (Trelstar) 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.


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.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.


All information has been provided courtesy of MedLinePlus from the National Library of Medicine and from the FDA.