Yonsa is used together with a steroid medicine (prednisone or methylprednisolone) to treat prostate cancer that has spread to other parts of the body (metastatic) and cannot be treated with surgery or other medicines.

Yonsa may also be used for purposes not listed in this medication guide.

Use only as directed. Tell your doctor if you use other medicines or have other medical conditions or allergies.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Yonsa is usually taken once per day while also taking a steroid 1 or 2 times per day. Follow your doctor's dosing instructions very carefully.

Your Yonsa dose needs may change if you switch to a different brand, strength, or form of this medicine. Avoid medication errors by using only the medicine your doctor prescribes.

Your steroid dose needs may change if you have an infection or are under stress. Do not change your dose or stop using your steroid medicine without your doctor's advice.

Take this medicine with a full glass of water.

You may take Yonsa with or without food.

Take Zytiga on an empty stomach. Do not eat anything for at least 2 hours before or 1 hour after you take Zytiga.

Swallow the tablet whole and do not crush, chew, or break it.

Your blood pressure will need to be checked often, and you may need frequent blood tests. If you have diabetes, your blood sugar should be checked carefully, especially if you take pioglitazone or repaglinide.

You should not stop using Yonsa or your steroid medicine suddenly. Follow your doctor's instructions about tapering your prednisone dose.

Store at room temperature away from moisture and heat.

Yonsa is not for use by women or children.

Tell your doctor if you have ever had:

• liver disease;

• diabetes (especially if you use pioglitazone or repaglinide);

• heart problems, high blood pressure;

• a heart attack;

• low levels of potassium in your blood; or

• problems with your adrenal gland or pituitary gland.

Yonsa can harm an unborn baby if a woman is exposed to it during pregnancy. An this medicine tablet should not be handled by a woman who is pregnant or may become pregnant. The medicine from a broken tablet could be absorbed through the skin.

Yonsa can also harm an unborn baby if the father is taking Yonsa at the time of conception or during pregnancy.

Use effective birth control if your sex partner is pregnant or able to get pregnant. Keep using birth control for at least 3 weeks after your last dose.

Skip the missed dose and take the medicine the following day. Do not take two doses at one time.

Call your doctor for instructions if you miss more than one dose of Yonsa.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Do not eat food for at least 2 hours before you take Zytiga and for at least 1 hour after your dose. Food can increase the amount of Zytiga your body absorbs and may cause side effects.

Avoid taking an herbal supplement containing St. John's wort.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Yonsa may cause serious side effects. Call your doctor at once if you have:

• swelling in your ankles or feet, pain in your legs;

• fast or irregular heartbeats;

• a light-headed feeling, like you might pass out;

• severe headache, blurred vision, pounding in your neck or ears;

• pain or burning when you urinate;

• low red blood cells (anemia)--pale skin, tiredness, feeling light-headed or short of breath, cold hands and feet;

• low blood potassium--leg cramps, constipation, irregular heartbeats, fluttering in your chest, increased thirst or urination, numbness or tingling, muscle weakness or limp feeling;

• liver problems--stomach pain (upper right side), nausea, vomiting, dark urine, jaundice (yellowing of the skin or eyes); or

• severe low blood sugar--headache, hunger, sweating, irritability, dizziness, fast heart rate, and feeling anxious or shaky.

Common side effects of Yonsa may include:

• feeling very weak or tired;

• feeling very hot;

• high blood sugar;

• increased blood pressure;

• swelling in your legs or feet;

• anemia, low blood potassium;

• painful urination;

• abnormal liver function tests or other blood tests;

• joint pain or swelling;

• headache;

• nausea, vomiting, diarrhea; or

• cold symptoms such as stuffy nose, sneezing, cough, sore throat.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Tell your doctor about all your current medicines. Many drugs can affect Yonsa, especially:

• other prostate cancer medicines, especially radium Ra 223 (may increase your risk of fractures while you are taking Yonsa); or

• pioglitazone or repaglinide to treat diabetes (may cause severe low blood sugar hypoglycemia while you are taking Yonsa.

This list is not complete and many other drugs may affect Yonsa. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.