Trade/other name(s): Zytiga
Why would this drug be used?
Abiraterone is used to treat advanced prostate cancer. It is also being studied for use in other cancers.
How does this drug work?
Abiraterone belongs to the general class of drugs known as hormones or hormone antagonists. It works by blocking an enzyme called CYP17. This enzyme normally helps certain cells in the body make male hormones called androgens, such as testosterone. Since prostate cancer usually depends on androgens to help it grow and spread, this helps stop it from growing.
Before taking this medicine
Tell your doctor…
- If you are allergic to anything, including medicines, dyes, additives, or foods.
- If you have high blood pressure. Abiraterone may raise blood pressure. Your doctor will probably want to monitor this closely during treatment.
- If you have any type of liver disease (including hepatitis). This drug is cleared from the body mainly by the liver. It may also affect the liver itself. Reduced liver function might result in more drug than expected staying in the body, which could lead to unwanted side effects. The dose of abiraterone may need to be reduced in people whose liver is not functioning well.
- If you have a history of problems with your pituitary gland or adrenal glands. This drug may affect the function of these glands.
- If you have ever been diagnosed with any type of heart disease, including an abnormal heart rhythm or congestive heart failure. This drug may affect the heart or cause a change in its electrical activity, which could lead to irregular heartbeats and could be life threatening.
- If you have any other medical conditions such as kidney disease, diabetes, gout, or infections. These conditions may require that your medicine dose, regimen, or timing be changed.
- If you are pregnant, trying to get pregnant, or if there is any chance of pregnancy. This drug can cause problems with the fetus if taken at the time of conception or during pregnancy. Women who are pregnant or may become pregnant should not take this drug, or even handle it without gloves. Men having sex with a woman who is or may become pregnant should use effective birth control, including condoms, during treatment and for at least one week after treatment.
- If you are breast-feeding. While no studies have been done, this drug may pass into breast milk and affect the baby. Breast-feeding is not recommended during treatment with this drug.
- If you think you might want to have children in the future. It is not known whether this drug can affect fertility. If this is a concern, talk with your doctor about the possible risk with this drug and the options that may preserve your ability to have children.
- About any other prescription or over-the-counter medicines you are taking, including vitamins and herbs. In fact, keeping a written list of each of these medicines (including the doses of each and when you take them) with you in case of emergency may help prevent complications if you get sick.
Interactions with other drugs
Abiraterone may interact with a number of drugs and supplements, so it is important to check with your health care team before starting or stopping any medicines.
The following drugs and supplements may lower the levels of abiraterone in the blood and may make it less effective:
- Anti-seizure drugs, such as carbamazepine (Tegretol), phenobarbital (Luminal), and phenytoin (Dilantin)
- Drugs to treat tuberculosis (TB), such as rifampin (Rifadin, Rimactane; also in Rifamate and Rifater) and rifabutin (Mycobutin)
- Dexamethasone (Decadron), a steroid drug
- St. John's wort (herbal dietary supplement)
The following drugs may cause levels of abiraterone to build up in the body, raising the risk of serious side effects:
- Nefazodone (Serzone), an antidepressant
- Antibiotics such as erythromycin (EES), clarithromycin (Biaxin), and telithromycin (Ketek) Anti-fungal drugs such as ketoconazole (Nizoral), itraconazole (Sporanox), and voriconazole (Vfend),
- HIV drugs such as indinavir, ritonavir, saquinavir, nelfinavir, atazanavir, and others
Abiraterone may also change the blood levels of other drugs you are taking, including:
- Antidepressant drugs, such as fluoxetine (Prozac), paroxetine (Paxil), venlafaxine (Effexor), imipramine (Tofranil), and amitriptyline (Elavil)
- Antipsychotic drugs, such as haloperidol (Haldol), resperidone (Risperdal), perphenazine (Trilafon), and thioridazine (Mellaril)
- Opioid pain relievers, such as codeine, tramadol (Ultram), and oxycodone
- Beta blocker drugs, such as metoprolol (Lopressor), carvedilol (Coreg), and timolol (Betimol)
- Heart rhythm drugs, such as flecainide (Tambocor), lidocaine, propafenone (Rythmol), and mexiletine (Mexitil)
- Dextromethorphan, a common cough suppressant in many non-prescription drugs
- Ondansetron (Zofran), an anti-nausea drug
If you take any of these drugs, your doctor may need to adjust your dose or change the drugs you are taking. There may be other drugs that interact with abiraterone as well. Do not start or stop taking any medicines or supplements while on abiraterone without talking with your doctor first.
Interactions with foods
It is very important to take this drug on an empty stomach (see below). Taking it with food could greatly increase the amount of drug absorbed by the body, which could cause serious side effects.
Grapefruit and grapefruit juice may affect the amount of abiraterone in the body. Check with your doctor, nurse, or pharmacist about whether you should avoid these, and whether any other specific foods may be a problem.
Tell all the doctors, dentists, nurses, and pharmacists you visit that you are taking this drug.
How is this drug taken or given?
Abiraterone is taken daily as tablets. Swallow the tablets whole with water. It is very important to take the tablets on an empty stomach – do not eat food for 2 hours before and for 1 hour after taking the tablets.
The usual starting dose of abiraterone is 1,000 milligrams (mg) once a day. People with liver problems may need to start at a smaller dose. The daily dose might need to be adjusted if you have side effects.
A corticosteroid drug called prednisone should be taken along with this drug. Prednisone is taken as a tablet twice a day.
If you are already taking a type of hormone therapy drug called an LHRH agonist, such as leuprolide (Lupron), goserelin (Zoladex), triptorelin (Trelstar), or histrelin (Vantas), it is important to keep taking this drug as well. Talk to your doctor about this.
Take abiraterone exactly as directed by your doctor. If you do not understand the instructions, ask your doctor or nurse to explain them to you. Keep the medicine in a tightly closed container away from heat and moisture and out of the reach of children and pets.
This drug may interact with a number of other drugs or supplements in the body — see "Interactions with other drugs" above. Be sure your doctor is aware of all drugs and supplements you are taking. Do not start or stop taking any drug without talking to your doctor about all the drugs you are taking.
Abiraterone may cause high blood pressure, low blood potassium levels, and fluid buildup in the body, all of which can affect the heart. Tell your doctor if you have a history of high blood pressure, congestive heart failure, or any type of heart disease. Your doctor will check your blood pressure and do blood tests regularly during treatment. Tell your doctor or nurse right away if you feel dizzy, faint, or light-headed, or if you have confusion, headaches, a fast heartbeat, weakness, pain in your legs, or swelling in your feet.
People with severe liver problems should not take this drug. Those with less serious liver problems may be able to take it at a reduced dose. This drug can also damage the liver. Your doctor will order blood tests and will check you for signs of liver problems before and during treatment to make sure your liver is working well. Tell your doctor or nurse right away if you have yellowing of the skin or the whites of your eyes (jaundice), dark urine, nausea or vomiting, pain on the right side of your belly, or any abnormal bruising or bleeding. If the drug affects your liver, the dose of abiraterone may need to be reduced or delayed, or the drug may need to be stopped altogether.
This drug may affect the adrenal glands, which may alter how your body handles stress (both physical and emotional). In rare cases this may cause severe low blood pressure that can lead to passing out or even death during stressful periods or if you have an infection or surgery. Be sure to take prednisone with this drug, which can help counteract these problems. Tell your doctor or nurse if you are aware of upcoming stressful situations, as your dose of prednisone may need to be increased for a short time.
Possible side effects
You will probably not have most of the following side effects, but if you have any talk to your doctor or nurse. They can help you understand the side effects and cope with them.
- Joint pain, stiffness, or swelling
- Muscle aches
- Fluid buildup (usually in the feet)*
- Low blood potassium levels*
- Hot flashes
- Urinary tract infection
- High blood pressure*
- Frequent urination, especially at night
- Abnormal heart rhythm
- Upset stomach
- Abnormal blood test results that suggest the drug is affecting the liver (Your doctor will discuss the importance of this finding, if any.)*
- Chest pain
- Heart failure*
- Adrenal gland problems*
*See "Precautions" section for more detailed information.
There are some other side effects not listed above that can also occur in some patients. Tell your doctor or nurse if you develop these or any other problems.
Yes – first approved in 2011.
Disclaimer: This information does not cover all possible uses, actions, precautions, side effects, or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for talking with your doctor, who is familiar with your medical needs.
Last Revised: 05/04/2011