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Bicalutamide (Casodex)

Find out what bicalutamide is, how you have it and other important information about having bicalutamide.

Bicalutamide is a cancer treatment drug and is also known by its brand name, Casodex.

It is a treatment for prostate cancer.

How it works

Prostate cancer needs the male hormone testosterone to grow. Testosterone is also called an androgen. 

Bicalutamide is a type of hormone drug called an anti androgen. It stops testosterone from reaching the cancer cells. This can slow the growth of your cancer and may shrink it.

How you have it

Bicalutamide is a tablet you take once a day.

You should swallow the tablet whole with a glass of water. 

Taking tablets

You must take tablets according to the instructions your doctor or pharmacist gives you.

Speak to your pharmacist if you have problems swallowing the tablets.

Whether you have a full or an empty stomach can affect how much of a drug gets into your bloodstream.

You should take the right dose, no more or less.

Talk to your specialist or advice line before you stop taking a cancer drug.

When you have bicalutamide

Bicalutamide is a treatment for prostate cancer. You might have bicalutamide:

  • on its own
  • after radiotherapy
  • after an operation to remove your prostate (prostatectomy)
  • before you have other hormone treatments such as goserelin (Zoladex), leuprorelin and triptorelin

Reducing tumour flare

You need to take bicalutamide before you start some other types of hormone treatment because they take a few weeks to lower your testosterone. During this time they can make your symptoms worse. This is called tumour flare. 

If you are having bicalutamide to stop tumour flare, you take it for a few days before starting the luteinising hormone blocker, and stay on it for about 4 to 6 weeks. 


You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

Side effects

Important information

Other medicines, food and drink

Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.


It is important not to father a child while you are having treatment with this drug and for a few months afterwards. This drug may harm a baby developing in the womb. Talk to your doctor or nurse about effective contraception before starting treatment. 

Loss of fertility

This treatment might stop you being able to father a child.

Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

You may be able to store sperm before starting treatment.

Usually, fertility returns to normal after a few months or sometimes years. You can have sperm counts to check your fertility when your treatment is over. Ask your doctor about it.

Lactose and bicalutamide

This drug contains lactose (milk sugar). If you have an intolerance to lactose, contact your doctor before taking this medicine.

Treatment for other conditions

Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment if you need treatment for anything else, including teeth problems.

More information about this treatment

We haven't listed all the very rare side effects of this treatment. For further information see the electronic Medicines Compendium (eMC) website.

You can report any side effect you have that isn’t listed here to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.

Information and help

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