Abiraterone acetate (Zytiga®)

Abiraterone is a hormonal therapy drug used to treat advanced prostate cancer. It’s best to read this with our general information about prostate cancer.

You have abiraterone as tablets. You usually have it as an outpatient. Your cancer doctor or nurse will tell you how often you will have it.

Like all hormonal therapy drugs, abiraterone can cause side effects. Some of these can be serious, so it’s important to read the detailed information below. How hormonal therapy affects people varies from person to person. Your doctor or nurse can talk to you more about this and give you advice on how to manage any side effects.

Tell your doctor or nurse straight away if you feel unwell or have severe side effects, including any we don’t mention here. If you need to see a health professional for any reason other than cancer, always tell them that you are having this treatment.

How abiraterone works

Hormones are substances produced naturally in the body. They act as chemical messengers and help control the activity of cells and organs. Hormonal therapies are drugs that interfere with the way hormones are made or how they work in the body.

Most prostate cancers need the hormone testosterone to grow. Almost all testosterone in men is made by the testicles. A very small amount is made by the adrenal glands above the kidneys.

Abiraterone reduces the amount of testosterone made by the body. This may shrink the prostate cancer or stop it growing.


When abiraterone is given

Abiraterone is used to treat prostate cancer that has spread to other parts of the body (advanced cancer). It can be used alone or alongside other types of treatment. If you’re already taking a hormonal therapy drug such as goserelin (Zoladex®) or leuprorelin (Prostap®), your doctor may ask you to continue taking it while taking abiraterone.

Your doctor or nurse will explain how long you should take abiraterone for.


Taking your abiraterone tablets

You take abiraterone as tablets once a day. You take it at the same time each day. Always take your tablets exactly as your nurse or pharmacist explained. This is important to make sure they work as well as possible for you.

You should not take abiraterone with food. Take the tablets at least two hours after eating then don’t eat for another hour. Many people take abiraterone an hour before breakfast. Swallow the tablets whole with a glass of water and don’t crush or chew them.

You will also be given steroid tablets called prednisolone to take every day. These help reduce some of the side effects of abiraterone.

Do not stop taking any of your tablets unless your doctor tells you to. Here are some important things to remember:

  • If you forget to take your tablets, just take your usual dose the next day. Don’t take a double dose.
  • Keep tablets in the original package and at room temperature, away from heat and direct sunlight.
  • Keep them safe and out of the sight and reach of children.
  • Get a new prescription before you run out of tablets and make sure you have plenty for holidays.
  • Return any remaining tablets to the pharmacist if your treatment is stopped.


Possible side effects of abiraterone

We explain the most common side effects of abiraterone here. We also include some rarer side effects. You may get some of the side effects we mention, but you are very unlikely to get all of them. If you are taking other drugs as well, you may have some side effects that we don’t list here.

You will see a doctor or nurse regularly while you have this treatment. Always tell your doctor or nurse about the side effects you have. They can prescribe drugs to help control them and give you advice about managing them. Don’t stop taking abiraterone or steroid tablets without talking to your doctor first.

More information about this drug

We’re not able to list every side effect for this treatment here, particularly the rarer ones. For more detailed information you can visit the electronic Medicines Compendium (eMC).

Build-up of fluid

You may put on weight or your ankles and legs may swell because of fluid building up. Tell your doctor or nurse if you notice this. If your ankles and legs swell, it can help to put your legs up on a foot stool or cushion. The steroid tablets your doctor prescribes will help to prevent this.

Low blood potassium

Abiraterone can cause low levels of potassium in the blood. Usually the steroid tablets prevent this. You will have blood tests regularly during treatment to check your potassium levels. 

If your levels are very low, you may need treatment and your doctor may tell you to stop taking abiraterone. Symptoms of low potassium levels include:

  • weakness
  • twitching muscles
  • feeling that your heart is beating harder or faster than usual.

If you notice these symptoms, contact a doctor straight away for advice.

High blood pressure

Abiraterone may cause this. Tell your doctor or nurse if you have ever had any problems with your blood pressure. You will have regular blood pressure checks when taking this drug. Let your doctor or nurse know if you have any headaches.

Risk of infection

Abiraterone can make you more likely to get an infection. The most common type of infection when you are taking this drug is a urine infection. Some men develop serious infections and need treatment in hospital. It’s important to contact your doctor if you have signs of infection such as:

  • cloudy or smelly urine, pain or discomfort when passing urine
  • feeling shivery
  • fever
  • sore throat or cough
  • diarrhoea.

Diarrhoea

Abiraterone can also cause diarrhoea without infection. Your doctor can prescribe anti-diarrhoea tablets if needed. Drink plenty of fluids if you have diarrhoea – at least two litres (about three and a half pints) a day.

Changes in the way the heart works

Abiraterone can affect the way the heart works. If this happens, it’s usually temporary and can be treated with medication. You will have tests to see how well your heart is working before, during and sometimes after treatment.

Tell a doctor straight away if at any time during or after treatment you:

  • have pain or tightness in your chest
  • feel breathless
  • notice changes to your heartbeat.

These symptoms can be caused by other conditions but it’s important to get them checked by a doctor.

Feeling sick

You may feel sick or have indigestion while taking abiraterone. This is usually mild. Your doctor can give you tablets to help if needed.

Changes in the way the liver works

Abiraterone may affect how your liver works. This is usually mild and goes back to normal after treatment. You will have blood tests to check how well your liver is working.

Skin rashes

You may get a mild skin rash while taking abiraterone. This often gets better without treatment. Tell your doctor if you have a rash.

Sexual effects

Most men lose their sex drive and have erection difficulties (impotence) during hormonal therapy. Things often return to normal after you stop taking the drug, but some men continue to have difficulties after treatment is over. Your doctor can prescribe treatments to help with erection difficulties but these don’t affect sex drive.

If you need support coping with sexual difficulties, your nurse or doctor can give you information and refer you for specialist support services.

Anaemia (low number of red blood cells)

Abiraterone can reduce the number of red blood cells in your blood. These cells carry oxygen around the body. If the number of red blood cells is low, you may be tired and breathless. Tell your doctor or nurse if you feel like this.

Raised blood sugar levels

Steroids can raise your blood sugar levels. Your nurse will check your blood regularly for this. They may also test your urine for sugar. Symptoms of raised blood sugar include feeling thirsty, needing to pass urine more often and feeling tired. Tell your doctor or nurse if you have these symptoms.

If you have diabetes, your blood sugar levels may be higher than usual. Your doctor will talk to you about how to manage this. You may need to adjust your insulin or tablet dose.


Possible side effects of abiraterone with long-term use

Bone thinning (osteoporosis)

Taking abiraterone will, over time, increase your risk of bone thinning (osteoporosis). In some men this can increase the risk of a broken bone (fracture). Your doctor can give you advice on how your bone health can be monitored. They can also tell you about treatments for bone thinning. Regular walking and resistance exercises, such as lifting weights, can help to keep your bones strong. Eating a healthy diet, not smoking and sticking to sensible drinking guidelines will also help to protect your bones. Let your doctor know if you have any discomfort in your bones or joints.

We have more information on our website about bone health.

It is important to tell your doctor or nurse straight away if you feel ill or have severe side effects. This includes any we don’t mention here.


Other information about abiraterone

Other medicines

Some medicines, including ones you can buy in a shop or chemist, can interact with or be harmful when you are having abiraterone. This includes the herbal remedy St John’s Wort. Tell your doctor about any medicines you are taking, including over-the-counter drugs, complementary therapies and herbal drugs.

Contraception

During treatment with abiraterone it’s important to use a condom if you have sex with someone who is pregnant. During and for a few months after treatment, you should use a condom and other contraception if you have sex with someone who may get pregnant.

This is because abiraterone may be in the semen and may harm a developing baby. Your doctor or nurse can give you more information about this.

Medical treatment

If you need to go into hospital for any reason other than cancer, always tell the doctors and nurses that you are taking abiraterone. Explain you are taking hormonal therapy and steroids and that no one should stop or restart these drugs without advice from your cancer doctor. Give them contact details for your cancer doctor so they can ask for advice.