How urinary catheters work 

Different types of urinary catheter work in different ways.

Intermittent urinary catheter

An intermittent urinary catheter is inserted just long enough to drain your bladder before being removed. It may be used up to four to six times a day.

It can be inserted yourself in a process known as clean intermittent self-catheterisation (CISC), which avoids the need for an indwelling catheter. This technique is usually taught to patients by a continence nurse. 

The catheter is usually inserted into your bladder via the urethra (the tube urine passes through out of your body). The sterilised catheter is lubricated with a sterile gel and a local anaesthetic cream or gel may be applied to numb the opening of your urethra, although this is not usually necessary.

One end of the catheter is either left open-ended to allow drainage into a toilet or attached to a bag to collect the urine. The other end is inserted into your urethra and guided through it until it enters your bladder and urine starts to flow.

When the flow of urine stops, the catheter can be moved or rotated. You may need to change positions to ensure all the urine has been emptied from your bladder. The catheter can then be removed. A new catheter is likely to be used each time.

Indwelling urinary catheter

An indwelling urinary catheter is inserted in the same way as an intermittent catheter, but the catheter is left in place.

Most indwelling catheters are not suitable to remain in place for longer than three months, so will need to be changed regularly.

The catheter is held in the bladder by a water-filled balloon, which prevents it falling out. These types of catheters are often referred to as Foley catheters.

Urine is drained through a tube connected to a collection bag, which can either be strapped to the inside of your leg or attached to a stand on the floor.

Indwelling catheters are not always free-draining and the catheter is sometimes fitted with a valve. The valve can be opened to allow urine to be drained into a toilet and closed to allow the bladder to fill with urine until drainage is convenient.

Suprapubic catheterisation

A suprapubic catheter is a type of indwelling catheter. Rather than being inserted through your urethra, the catheter is inserted through a hole in your abdomen and then directly into your bladder. This procedure can be carried out under general anaesthetic or local anaesthetic.

A suprapubic catheter is used when the urethra is damaged or blocked, or when a person has a long-term condition and is unable to use a clean intermittent catheter.

The catheter may be taped to the side of your body and run down to a collection bag strapped to your leg. Alternatively, a valve can be attached that opens to allow urine to be drained into a toilet, and closes to allow the bladder to fill with urine until drainage is convenient.

The catheter will need to be changed regularly and is not usually left in place for more than three months.

Page last reviewed: 26/03/2013

Next review due: 26/03/2015