Bicalutamide (Casodex)

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Your doctor has recommended a medication called Casodex as treatment for your prostate cancer. This page provides extra information about your medicine, summarises possible side effects and methods to alleviate them.

What is in Casodex? Bicalutamide is an oral tablet taken once a day, at a dose of either 50mg or 150mg.  It belongs to group of medicines called anti-androgens . They are used to treat  male patients with prostate cancer. Many men like to take it at the same time each day – the actual time does not matter. Some men prefer to take it with food or some prefer to take it last thing at night - try to find a convenient time and stick to it as its easier to remember to take the tablets in the long term.

If you forget to take your tablet don’t panic – levels of the drug in your blood will not change very much – but try  not to miss more than one or two tablets in a row. Remember to get a new prescription a couple of weeks before you run out of the tablets and make sure you have plenty for holidays etc.

 How do they work? Some tumours such as prostate cancer are stimulated by the body's own male hormone (Testosterone). Stopping the body's testosterone reaching the tumour can cause the cancer cells to stop growing and in some cases shrivel up and die completely (self destruct - apoptosis).  Casodex stops testosterone stimulating a cancer cell by stopping  the cancer cells ability to read the testosterone in the blood stream. Cancer cells have receptors in the same way as a TV needs an aerial. If the aerial is damaged the TV can't show a clear picture. In the same way if the receptor on the cell is blocked it can't be influenced by the body's hormones, despite often normal levels in the blood stream. In this case the receptors are called androgen receptors and are blocked by Casodex. This is why Casodex is sometimes referred to as a receptor antagonist.

How will I & the doctor know they are working?  In most cases there is something the doctor can measure. This may be how you feel, a symptom related to your cancer, something which can be felt on examination (e.g. a lump or size of prostate),   something seen on a scan or Xray or a blood test called PSA, (the level of which will get lower if you are responding).

Possible side effects: All medications have side effects. These can affect some people more than others. It is hard to predict the level and type of side effect for each individual. Listed below are an overview of the more common side effects you may encounter, however, you may experience none, all, or only a few of these. You may also have a rare side effect not listed here - If you become aware of any other side effects, please report them to your clinic.

If side effects are severe, you may have to stop taking the drug and a different hormonal drug may be prescribed.

• Breast swelling (gynaecomastia) - Often the breasts can become tender and enlarge (this can be prevented by a low dose of radiotherapy to the nipples as soon as it starts or before starting Casodex).

• Damage to the liver - Casodex may accumulate in the liver, if you have a pre-existing liver condition, therefore you must tell your doctor about this before starting Casodex.

• Sex drive (libido)  - The advantage of Casodex is that it may not have a major impact on the sex drive. It may in some cases impair the ability to have erections.

• Nausea and indigestion - Feelings of mild sickness (nausea) and vomiting can occur rarely but usually wear off after a few weeks. see diet and indigestion

Less common side effects include:

• Allergic reactions – this may include skin rashes

• Temporary thinning of the hair

• Rare cardiovascular effects such as angina, heart failure have occurred with Casodex
• Abdominal discomfort
• Headaches – some people affected by migraine have noticed a change in the pattern of their headaches

Other issues There is no interaction between Casodex and moderate amounts of alcohol. Casodex does not usually affect your ability to drive.