Bicalutamide (Casodex ®)
Bicalutamide is a hormonal therapy drug used to treat prostate cancer. This information is best read with our general information about prostate cancer. You will see a doctor or nurse regularly while you have this treatment so they can monitor its effects.
How bicalutamide works
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Hormones are substances produced naturally in the body. They act as chemical messengers and help control the activity of cells and organs. Hormonal therapies 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, which sit above the kidneys.
Bicalutamide blocks testosterone from reaching the cancer cells. Without testosterone the prostate cancer may shrink or stop growing.
When bicalutamide is given
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Early prostate cancer
This is when the cancer is contained in the prostate and has not spread to other parts of the body. Bicalutamide may be given short-term (for a few weeks) with other treatments for early prostate cancer. It is used to manage a condition called tumour flare that can happen when starting hormonal treatments such as goserelin, buserelin, triptorelin or leuprorelin. Tumour flare is caused by a temporary increase in testosterone levels; this can lead to an increase in symptoms, such as problems passing urine. Bicalutamide may be given for the first few weeks of these treatments to prevent this.
Advanced prostate cancer
Bicalutamide is also used to treat prostate cancer that has spread to other parts of the body (advanced prostate cancer). Bicalutamide may be given after surgery or radiotherapy. It can be given on its own or with other hormonal treatments such as goserelin, buserelin, triptorelin or leuprorelin which reduce testosterone levels. Your doctor or nurse will explain how long you will have bicalutamide treatment. Treatment may continue for as long as it works to control your cancer.
We have a factsheet and more information on our website about early prostate cancer and advanced prostate cancer.
Taking your bicalutamide tablets
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Bicalutamide is taken as a tablet once a day. You take it at the same time each day. Swallow the tablet whole with a drink of water. 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.
It’s important that you do not stop taking any of your tablets unless advised by your doctor. Here are some important things to remember:
If you forget to take your tablet, do not take a double dose. Just take your usual dose the next day. The levels of the drug in your blood will not change very much.
Keep tablets in the original package, and at room temperature away from heat and direct sunlight.
Keep them safe and out of the 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 bicalutamide
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We explain the most common side effects of bicalutamide here. But we don’t include all the rare ones that are unlikely to affect you. 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.
Always tell your cancer doctor or nurse about the side effects you have. They can prescribe drugs to help control them and give you advice about managing them.
Breast swelling or tenderness
This is a common side effect with longer term treatment with bicalutamide. It is called gynaecomastia. Your doctor can advise you on how it can be prevented or treated. You may have one or two treatments with low-dose radiotherapy to the breast tissue, or weekly treatment with a hormone drug.
Bicalutamide may reduce your sex drive or you may notice difficulty with erections. Your nurse or doctor can give you information about this and, if required, refer you for specialist support services.
Hot flushes and sweats
These are common and can be mild or more severe. During a hot flush, you feel warmth in your neck and face and your skin may redden. Mild flushes last for a few seconds up to about a couple of minutes. More severe flushes can last for 10 minutes or more. You may have sweats and then feel cold and clammy. Some people feel anxious or irritable during a hot flush.
There are things you can do to try to reduce hot flushes, such as cutting down on nicotine, alcohol and hot drinks that contain caffeine, such as tea and coffee.
If hot flushes are troublesome, your doctor can prescribe drugs to help reduce them.
Hot flushes and sweats may reduce as your body adjusts to hormonal treatment. They usually stop completely a few months after treatment finishes.
We have more information on our website about prostate cancer and hormonal symptoms.
Anaemia (low number of red blood cells)
Bicalutamide 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.
Skin rashes or dryness
Occasionally people develop a mild skin rash. This often gets better without treatment. Tell your doctor if you have a skin rash.
This is usually mild. It might help to take your bicalutamide tablets with food. Your doctor can prescribe anti-sickness drugs if needed.
Weight gain and loss of muscle strength
You may gain weight, particularly around your waist, and you may lose some muscle strength. Eating a healthy diet and keeping physically active can help control your weight. Ask your doctor or nurse for advice.
Some men notice that their hair becomes thinner, but this is usually mild. Others may notice their hair gets thicker during treatment.
Constipation or diarrhoea
Bicalutamide may make you constipated. Drinking at least two litres of fluids (three and a half pints) every day will help. Try to eat more foods that contain fibre (such as fruit, vegetables and wholemeal bread) and take some regular gentle exercise.
Let your doctor or nurse know if this happens. They can give you medicine to help your bowels move (laxatives).
Occasionally, bicalutamide can cause diarrhoea. Drink at least two litres (three and a half pints) of fluids every day if you have diarrhoea. Your doctor can prescribe anti-diarrhoea tablets if needed.
Tummy or back pain
You may get pain or discomfort in your tummy (abdomen) or back, feel bloated or have indigestion or wind. Peppermint capsules and mint tea may help with indigestion or wind. Tell your doctor if any pain or discomfort doesn’t improve or gets worse. They can prescribe drugs to help improve these symptoms.
Blood in your urine
You may have blood in your urine while taking bicalutamide. This is quite common. Tell your doctor or nurse if you notice this.
Dizziness or drowsiness
Tell your doctor or nurse if you have either of these symptoms. It’s important not to drive or operate machinery if you are affected.
Less common side effects of bicalutamide
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Rarely, bicalutamide may cause an allergic reaction. Signs of a reaction can include a rash, feeling itchy, flushed or short of breath, swelling of your face or lips, or feeling dizzy or unwell. Contact your doctor straight away if you have any of these symptoms.
Effect on liver
Bicalutamide can sometimes affect the liver. Your doctor will do regular blood tests to check your liver. Usually any effect is mild and you can continue to take bicalutamide. Tell your doctor if you notice any yellowing of your skin or eyes.
Rarely, bicalutamide can cause breathlessness. If you feel breathless while taking bicalutamide, tell your doctor straight away.
Always let your doctor or nurse know about any side effects you have. There are usually ways in which they can be controlled or improved.
Other information about bicalutamide
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Bicalutamide can interact with other drugs. This includes medicines you can buy in a supermarket or chemist. Tell your doctor about any medicines you are taking. These include ones you can buy yourself, such as complementary therapies, antihistamines, vitamins and herbal drugs.
If you need to go into hospital for any reason other than cancer, always tell the doctors and nurses that you are taking bicalutamide. Explain you are taking hormonal therapy and that no one should stop or restart without checking with your cancer doctor first. Tell them the name of your cancer doctor so they can ask for advice.
It’s a good idea to know who you should contact if you have any problems or troublesome side effects when you’re at home.
The information in this section has been produced in accordance with the following sources and guidelines:
British National Formulary. www.bnf.org/bnf/index.htm (accessed June 2014)
electronic Medicines Compendium (eMC). www.medicines.org.uk (accessed June 2014)
NICE clinical guideline 175. Prostate cancer: diagnosis and treatment. 2014.
If you’d like further information on the sources we use, please feel free to contact us.
Thanks to Rena Chauhan, Lead Pharmacist, who reviewed this information.
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