SIDE EFFECTS: Hot flashes, headache, dizziness, or decreased sexual interest/ability may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if you have any serious side effects, including: back pain, numbness/tingling/weakness/pain of the arms or legs, falls, broken bones, pink/red urine. This medication may raise your blood pressure. Check your blood pressure regularly and tell your doctor if the results are high. Get medical help right away if you have any very serious side effects, including: persistent headache, decreased alertness, seizures, sudden vision changes, mental/mood changes (such as memory problems, confusion). This medication may lower your ability to fight infections. This may make you more likely to get a serious (rarely fatal) infection or make any infection you have worse. Tell your doctor right away if you have any signs of infection (such as fever, chills, persistent sore throat, cough). A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking enzalutamide, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: high blood pressure, seizures, risk factors for having seizures (such as brain injury, stroke, brain tumor). Since this medication may rarely cause seizures in some people, ask your doctor if you should avoid activities where a sudden loss of consciousness may cause serious harm to you or others. This drug may make you dizzy. Alcohol or marijuana can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana. Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). This medication should not be used in women, especially during pregnancy or breast-feeding. It may harm an unborn or breast-feeding baby. Consult your doctor for more details. Men who have a pregnant partner must use a condom during sexual activity during enzalutamide treatment and for 3 months after treatment has stopped. Men with a female partner of childbearing age who is not pregnant should use a condom and another form of birth control during enzalutamide treatment and for 3 months after treatment has stopped. Ask your doctor for more details. If your partner becomes pregnant or thinks she may be pregnant, tell the doctor right away.

DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Other medications can affect the removal of enzalutamide from your body, which may affect how enzalutamide works. Examples include rifamycins (such as rifabutin, rifampin), seizure medications (such as phenobarbital, phenytoin), St. John's wort, among others. Enzalutamide can speed up the removal of other medications from your body, which may affect how they work. Examples of affected drugs include asunaprevir, cobicistat, ergot alkaloids (such as dihydroergotamine, ergotamine), fentanyl, lurasidone, pimozide, quinidine, sirolimus, suvorexant, tacrolimus, voriconazole, among others.

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include seizures.