When you stop taking Casodex (bicalutamide) it takes approximately 30 days for most of the Casodex to be removed from your body. If you have severe liver impairment it will take longer (up to 50 days).

What happens when you stop Casodex will depend on the reason why you are stopping it.

• If you are stopping Casodex due to excessive or problematic side effects you may find that your side effects reduce over the first 30 to 50 days depending on your liver function. Once you stop taking Casodex the antiandrogen effect will also stop.

• If you are stopping Casodex as your doctor has decided it is no longer beneficial for you, your health care professional will be able to discuss what further options may be available to you.

A subset of patients who stop Casodex treatment develop antiandrogen withdrawal syndrome, this is when after stopping Casodex the patient has a decrease in prostate-specific antigen (PSA) and they may benefit from a clinical improvement. At this stage antiandrogen withdrawal syndrome is not fully understood and it is not possible to identify which patients will respond in this positive way to Casodex withdrawal.

• In a small study of advanced prostate cancer patients, who had an antiandrogen stopped, 13 out of 44 patients (29%) had a decrease in the PSA and 11 out of 44 (25%) the decrease was greater than 50%.