This page is for patients who are having a trial without their indwelling urinary catheter (TWOC).

What is TWOC?

A trial without catheter is when a catheter which has been inserted via the urethra (water pipe) is removed from the bladder for a trial period to determine whether you are able to pass urine normally.

You may have been prescribed medication called an alpha blocker (men only) to take while your catheter is in place. It is important that you start taking these tablets at least 14 days before you attend your clinic appointment. You should continue to take this medication every day until your appointment. If you need more tablets before your appointment you should request them from your GP.

Before the appointment

You can eat and take all of your usual medication. If at all possible drink more fluids than your normal amount on the day of your appointment. If you are using a valve (specialist tap) on your catheter it will be helpful if you can come to the clinic with a full bladder. Try not to release the valve for 2 hours before your appointment. Please make sure that you have been opening your bowels regularly.

During the appointment

You will be in the department for several hours so the following may be useful:

  • You will be encouraged to drink water once your catheter has been removed. If you prefer you can bring you own drink.
  • As the appointment may extend over lunchtime you may wish to bring a snack with you, although if time permits you may be able to use the hospital cafe. This is especially important if you suffer from diabetes.
  • Please bring a list of your current medication.
  • You may wish to bring a book or something to read.
  • We also advise you to bring a change of underwear in case of incontinence.

You will be seen by a nurse who will ask you questions about your medical and urological history. The nurse will also answer any questions that you may have.

Your catheter will be removed and you will be asked to drink to fill your bladder.

When you feel the need to pass urine you will be asked to use a private, specially adapted, toilet so that the amount of urine passed can be measured each time. This is a simple, painless and non-invasive procedure.

After you have passed urine, the nurse will perform an ultrasound scan on your bladder. You will be asked to lie down on a couch and lower your clothing to show your abdomen. A small amount of gel will be placed on your abdomen and then the scan will be performed.

The ultrasound scan will be painless and will only take a few minutes.

If you are unable to empty your bladder and it becomes uncomfortable you should tell the nurse who will discuss a plan of options with you and help you make the right choice.


Once the investigation has been completed the nurse will discuss the results and any treatment needed. We will provide you with as much information as we can about your condition and treatment options before you leave the department. The outcome results will be forwarded to your consultant urologist.

Contact information

If you have questions or concerns please contact:

Painswick Suite

Cheltenham General Hospital

Tel: 0300 422 5193

Tel: 0300 422 3640

Tel: 0300 422 6911

Printable version of this page

Trial Without Catheter (TWOC) GHPI1411 Department: Urology Review due: September 2024 PDF, 411.0 KB, 2 pages
Reference number GHPI1411_09_21
Department Urology
Review due September 2024