What is bicalutamide?

Bicalutamide is a hormonal therapy drug used to treat prostate cancer. It can be given alone or with other types of treatment.

It is best to read this information with our general information about hormonal therapies and the type of cancer you have.

Your doctor will talk to you about this treatment and its possible side effects before you agree (consent) to have treatment.

More information about this treatment

This information is correct at time of publishing. But sometimes the types of cancer this treatment is used for, or treatment side effects, may change between revision dates.

You can talk to your cancer team if you want more detailed information about this treatment. Or visit the electronic Medicines Compendium (eMC) website, which has patient information leaflets (PIL) for individual drugs.

How bicalutamide works

Hormones are chemicals that our bodies make. Hormones act as messengers and help control how cells and organs work. Hormonal therapies are drugs that change the way hormones are made or how they work in the body.

Most prostate cancers need the hormone testosterone to grow. Testosterone is mostly made by the testicles. A very small amount is made by the adrenal glands, which sit above the kidneys.

Bicalutamide blocks testosterone from reaching the cancer cells. This may shrink the prostate cancer or stop it growing.

When bicalutamide is given

Bicalutamide may be given: 

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

Taking bicalutamide tablets

Bicalutamide comes as tablets you can take at home. 

You usually take bicalutamide once a day. Your nurse or doctor will talk to you about your treatment plan. Always take the tablets

exactly as explained. This is important to make sure they work as well as possible for you. Make sure you:

  • swallow them whole with a glass of water
  • do not chew, or crush the tablets
  • try to take them at the same time every day. 

If you forget to take the tablets, you should wait and take your normal dose the following day. Do not take a double dose to make up for the one you missed.

Other things to remember about your tablets:

  • Keep them in the original package and at room temperature, away from heat and direct sunlight.
  • Keep them safe and out of sight and reach of children.
  • If you are sick just after taking the tablets, contact your healthcare team. Do not take another dose.
  • Get a new prescription before you run out of tablets, and make sure you have plenty for holidays.
  • If your treatment is stopped, return any unused tablets to the pharmacist. 
  • Take all your medicines exactly as they have been explained to you. Do not stop taking any of your medicines unless your doctor tells you to.

About side effects

About side effects

We explain the most common side effects of this treatment here. We also include some that are less common. 

You may get some of the side effects we mention, but you are unlikely to get all of them. And you may have some side effects, including rarer ones, that we have not listed here. 

Other cancer treatments may cause different side effects. If you are also having other cancer treatment, you may have other side effects.

Always tell your doctor, nurse or pharmacist about any side effects you have. They can give you: 

  • drugs to help control some side effects 
  • advice about managing side effects. 

It is important to take any drugs exactly as explained. This means they will be more likely to work for you.

Serious and life-threatening side effects

Some cancer treatments can cause serious side effects. Sometimes, these may be life-threatening. Your doctor, nurse or pharmacist can explain the risk of these side effects to you.

Contact the hospital

Your doctor, nurse or pharmacist will give you 24-hour contact numbers for the hospital. If you feel unwell or need advice, you can call at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.

Common side effects

Hot flushes and sweats

Hot flushes are a common side effect of this treatment. During a flush, your neck and face may feel warm. If you have white skin, your skin may look red. If you have black or brown skin, your skin colour may deepen. Flushes can last up to 5 minutes. You might also have sweats or feel anxious or irritable during a flush. 

Here are some things you can do to reduce the effects of hot flushes:

  • Wear natural fabrics, such as cotton.
  • Wear layers so you can remove clothes as needed. 
  • Use cotton sheets and layers of bedding you can remove. 
  • Try cooling pads or pillows to keep you cool.
  • Keep rooms cool or use a fan.
  • Have cold drinks and avoid caffeine and alcohol. 

You might have fewer hot flushes as your body adjusts to this treatment. You could try therapies to help you cope with hot flushes, such as:

  • talking therapies like cognitive behaviour therapy (CBT)
  • controlled breathing exercises
  • yoga
  • acupuncture. 

If they do not improve, talk to your doctor. Certain drugs can help to improve hot flushes. 

Flushes usually stop a few months after treatment ends. But some people continue to have them.

Breast swelling or tenderness

This treatment may cause swelling and tenderness of your breast tissue. This is called gynaecomastia. To prevent this, some people have 1 or more low-dose radiotherapy treatments to the chest before treatment starts. Another type of hormonal drug might be used to treat the breast swelling. Your doctor can give you more advice.

Sexual effects

It is common to lose your sex drive and have erection difficulties with hormonal therapy. Hormonal therapy may also make your penis shorter and your testicles smaller. 

Your doctor can prescribe drugs and treatments to help with erection difficulties. These will not increase your sex drive. But they might work, even with a low sex drive. 

Things can improve a few months after you stop taking the drug. But it depends on how long you take hormonal therapy, and what other treatments you have had. Some people continue to have problems after treatment ends.

Feeling tired (fatigue)

Feeling tired is a common side effect. Try to pace yourself and plan your day so you have time to rest between activities.

Being physically active can help to manage tiredness and give you more energy. It also:

  • helps you sleep better
  • reduces stress
  • improves your bone health.

If you feel sleepy, do not drive or operate machinery.

Anaemia (low number of red blood cells)

This treatment can reduce the number of red blood cells in your blood. Red blood cells carry oxygen around the body. If the number of red blood cells is low, this is called anaemia. You may feel:

  • very low in energy
  • breathless 
  • dizzy and light-headed. 

If you have these symptoms, contact the hospital straight away on the 24-hour number. You may need treatment for anaemia. If you are very anaemic, you may need a drip to give you extra red blood cells. This is called a blood transfusion.

Skin changes

This treatment can affect your skin. It may cause a rash, which may be itchy. Your doctor or nurse can tell you what to expect. If your skin feels dry, try using soap-free cleansers and unperfumed moisturising cream every day. 

Always tell your doctor or nurse about any skin changes. They can give you advice and may prescribe creams or medicines to help. Changes to your skin usually improve when treatment ends.

Weight gain

You may gain weight when you are having this treatment. Eating healthily and being active can help you keep to a healthy weight. Your doctor, nurse or dietitian can give you more advice.

Feeling sick

You may feel sick when you are having this treatment. This is usually mild. Tell your doctor or nurse if you feel sick, they can give you advice. They may give you some tablets to help. It may also help to take your bicalutamide tablets with food.

Loss of appetite

This treatment can affect your appetite. Don’t worry if you do not eat much for 1 or 2 days. But if your appetite does not come back after a few days, or if you are losing weight, tell your doctor, nurse or pharmacist. They can give you advice. They may give you food or drink supplements. Or they may suggest changes to your diet or eating habits to help.

Constipation

This treatment can cause constipation. Constipation means that you are not able to pass stools (poo) as often as you normally do. It can become difficult or painful. Here are some tips that may help:

  • Drink at least 2 litres (3½ pints) of fluids each day.
  • Eat high-fibre foods, such as fruit, vegetables and wholemeal bread.
  • Do regular gentle exercise, like going for short walks.

If you have constipation, contact the hospital on the 24-hour number for advice. They can give you drugs called laxatives to help. 

If you have not been able to pass stools for over 2 days and are being sick, contact the 24-hour number straight away. 

Tummy pain

You may get indigestion, wind or pain in your tummy (abdomen). Tell your doctor or nurse if you notice this. They can give you treatments to help.

Dizziness or drowsiness

Tell your doctor or nurse if you have either of these symptoms. If you feel dizzy or drowsy, it is important not to drive or operate machinery.

Hair thinning

Your hair may become thinner when you are taking this treatment. This is usually mild. Ask your nurse for advice if you are worried about this.

Mood changes

You may feel low or depressed, or have mood swings, during this treatment. Talking to family and friends about how you feel might help. If mood changes last for more than a few weeks, tell your doctor, nurse or pharmacist. They can talk to you about different ways to manage low mood or depression.

Blood in your urine

You may have blood in your urine while taking bicalutamide. If you notice this, tell your doctor or nurse.

Effects on the liver

This treatment may affect how your liver works. This is usually mild. You will have blood tests to check how well your liver is working.

Effects on the heart

This treatment can affect the way your heart works. If there are any concerns, your doctor may do tests to see how well your heart is working.

Contact a doctor straight away if you:

  • have pain or tightness in your chest 
  • feel breathless or dizzy
  • feel your heart is beating too fast or too slowly.

 Other conditions can cause these symptoms. But it is important to get them checked by a doctor.

Less common side effects

Allergic reaction

This treatment might cause an allergic reaction. But this is not common. Signs of a reaction can include: 

  • a skin rash or itching
  • feeling breathless or wheezy
  • swelling of your face, mouth or throat.

If you feel unwell or have any of these signs, contact the hospital straight away on the 24-hour number. Do not take any more of this treatment until you have checked with them.

Effects on the lungs

This treatment can cause changes to the lungs. Tell your doctor, nurse or pharmacist if you develop: 

  • a cough that does not go away
  • wheezing
  • breathlessness.

You should also tell them if any existing breathing problems get worse. You may have tests to check your lungs.

Other information

Blood clot risk

Cancer and some cancer treatments can increase the risk of a blood clot. Contact the hospital straight away on the 24-hour number if you have any of these symptoms during or after treatment:

  • throbbing pain or swelling in a leg or arm
  • reddening of the skin in the area – if you have black or brown skin, this can be harder to notice, but the skin might become darker
  • suddenly feeling breathless or coughing.

Always call 999 if you have:

  • chest pain
  • difficulty breathing.

A blood clot is serious, but it can be treated with drugs called anticoagulants. These thin the blood. Your doctor, nurse or pharmacist can give you more information about preventing and treating blood clots.

Fertility

Some cancer drugs can affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.

Contraception

Your doctor, nurse or pharmacist will advise you not to get pregnant or make someone pregnant while having this treatment and for some time afterwards. The drugs may harm a developing baby. It is important to use contraception to prevent pregnancy. Follow their advice about:

  • what types of contraception to use 
  • how long after treatment you should continue to use contraception. 

Other medicines

Some medicines can affect how this treatment works or be harmful while you are having it. Always tell your cancer doctor, nurse or pharmacist about any drugs you are taking or planning to take, such as: 

Lactose

These tablets contain a type of sugar called lactose. If you have been told by a doctor that you cannot digest some sugars or are lactose intolerant, talk to your doctor before taking this drug.

Medical and dental treatment

If you need medical treatment for any reason other than cancer, always tell the healthcare professional that you are having cancer treatment. Give them the contact details for your cancer doctor or cancer team so they can ask for advice.

If you have appointments with a dentist, always tell them you are having cancer treatment. Talk to your cancer team before you have any dental treatment.

About our information

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert health professionals and people living with cancer.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We want our information to be as clear as possible. To do this, we try to:

  • use plain English
  • explain medical words
  • use short sentences
  • use illustrations to explain text
  • structure the information clearly
  • make sure important points are clear.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected.

You can read more about how we produce our information here.

Date reviewed

Reviewed: 01 June 2022
|
Next review: 01 December 2024
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.