Overview

If you’re having radiotherapy to your pelvis, you’ll need to prepare your bladder for the treatment. You will need to practice drinking enough, and keeping your bladder full.   

Stay hydrated

The first step to preparing your bladder is to make sure you drink enough (stay hydrated) to keep your bladder comfortably full. A comfortably-full bladder means that your bladder feels full, but you do not need to pee urgently.

You should drink 2 to 3 litres of fluid each day, especially water or other non-caffeinated drinks. You should avoid too many fizzy or alcoholic drinks. Try to drink a glass of water every hour during the day, or more if the weather is hot or you are exercising.

Drinking enough fluid will help reduce the side effects of your treatment. This is because less of your bladder and bowel will be in the radiation beam. It will also mean that the treatment is given more accurately.

Keep your bladder full

To prepare for your CT planning scan and radiotherapy treatment, you’ll need to practice filling your bladder and keeping it full.

Try to empty your bladder and drink 350ml (about 2 small glasses) of water. Ideally you should be able to hold it in your bladder for 45 minutes. Do this every day, starting from the day you consent to the treatment.

If you cannot hold 350ml of water in your bladder and you need to pee, try reducing the amount to 300ml and holding it for 45 minutes.

If you still cannot hold it, try reducing the amount of fluid until you find an amount that is comfortable for you to hold for the full 45 minutes. Try to increase the amount of water each day until you are comfortable holding 350ml.

Your CT planning scan

Your radiographer will explain the procedure to you. For the CT scan and treatment, you’ll need to hold 350ml of fluid in your bladder for 30 to 45 minutes.

A member of staff will tell you when to start drinking. Before the CT scan we will check that your bladder is full enough. We may check this with a scan of your bladder. If it is not, you might need to drink more water or come back another day.