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  • Name:
  • Date of birth:
  • Hospital/NHS number:
  • Date of insertion:
  • Why was the catheter inserted?
  • Special instructions:
  • Catheter:
  • Type:
  • Balloon size:
  • Size/length:
  • Order no:

Leg bag:

  • Type:
  • Size:
  • Order no:
  • Date of insertion:
  • Planned date of removal:

Night bag:

  • Type:
  • Order no:




Next change due:

Change to be performed by:

A catheter is a thin, soft, hollow tube used to drain urine from your bladder. It is held in place by a small balloon, which is inflated with sterile water. The balloon is inside the bladder, so you should not try to remove the catheter yourself. The catheter drains urine from the bladder into a bag which should be emptied at regular intervals.

When the catheter is first placed, you may feel slight irritation or may feel you want to pass water. These sensations are common and should soon improve. It will help if you are able to relax. Some patients have bladder spasms for a while after the catheter has been fitted - medication prescribed by your GP may help.

If you notice blood in your urine or think you have an infection, please seek advice from a doctor or district nurse.

Catheters are inserted for a variety of reasons but the main reason is to drain urine out of the bladder. The catheter tube is passed up your urethra (water pipe) into the bladder and when in place a small balloon at the end of the catheter is filled with water. This keeps the tube from falling out. The catheter has small holes at the top to allow urine to drain out down the tube. This can drain into a urine drainage bag or you may have a catheter valve on the end which allows you to empty your bladder intermittently.



All treatments and procedures have risks and we will talk to you about the risks of catheterisation.

  • On insertion there may be some discomfort and bleeding
  • Having a catheter in means you are at risk of getting a urine infection
  • Catheters can block and stop draining
  • Catheters can bypass so that urine comes out around the tube causing a leak.
  • Can be pulled out if not anchored properly
  • Water can leak out of the balloon causing catheter to drop out
  • It may be difficult to remove catheter if balloon does not deflate
  • It may cause trauma to water pipe if not anchored securely

Your doctor and nurse specialist will discuss what problems not having a catheter inserted may cause in your particular case. Please feel free to ask them any questions.

In some cases intermittent catheterisation may be a possible alternative to having an indwelling catheter in place. This means inserting the catheter into your bladder yourself, allowing urine to drain and then removing the catheter until next time you need to empty. If this is so than your doctor may offer it as an alternative and you will be referred to the continence advisors who will take you through the procedure and teach you how to do this. If you have to have an indwelling catheter in then it may be possible to have a catheter valve on the end of it instead of a drainage bag. When you need to empty your bladder you can open the valve and drain the urine out into a toilet before closing the valve again.

If this is done on the ward or in outpatients all you need is to make sure you have had a shower or a wash in the area. There is no other preparation needed.

We want to involve you in all the decisions about your care and treatment. We do not routinely ask for written consent to insert a catheter. However staff will explain all the risks, benefits and alternatives to ensure you understand what it involves before they ask you if you wish to proceed. If you are unsure about any aspect of your proposed treatment, please don’t hesitate to speak with a senior member of staff again.

Unless you have the catheter inserted during an operation you will be asked to lie on a couch or bed in a semi sitting position. A pad may be put under your bottom to absorb any spillages. All the equipment needed will prepared at the bedside and a sterile towel will be placed across your thighs. Your nurse will advise you on the correct position to ensure the urethra (your waterpipe) can be seen. Before inserting the catheter tube the area around the opening of the urethra is gently cleaned with a sterile solution. Local anaesthetic gel is then put down the urethra. This should be left to work for three to five minutes. The gel also acts as a lubricant. The catheter is then gently inserted into the opening and pushed along the urethra and into the bladder. Urine usually starts to drain out at this point and then the balloon at the end of the catheter is inflated with sterile water, anchoring the tube in the bladder. The catheter is then either attached to a drainage bag or you will be fitted with a catheter valve. The catheter will be attached to your leg or abdomen to make sure it is supported and will not pull onto the urethra.

It is normal to feel slight irritation in the bladder because of the presence of the catheter. This makes you feel like you want to pass urine. You may also have bladder spasms. Your doctor may prescribe you some medication to lessen the spasms and make having the catheter more comfortable.

It is also normal to have a little bit of bleeding after catheter insertion. This should clear once you start drinking and begin to drain urine. If it does not clear and you start to pass clots please contact your GP/ Nurse/Nurse Specialist (see below).

Fluids and drainage

It is very important to drink plenty of fluids to keep the urine flowing. This helps reduce the risk of blockages in the tube and infection.

We recommend that you drink 10 to 12 cups of water a day (with squash or fruit juice), remember sometimes caffeine drinks like tea or coffee may irritate the bladder.

Cranberry juice can be beneficial and help in the prevention of infection (but if you are taking anticoagulants like warfarin, cranberry juice is not advised).

When you are able to walk around, try and do so regularly. This will help keep the tube draining freely.

Empty your leg bag when it is about three quarters full to prevent it from pulling.

Your urine should be a pale yellow colour. If it appears darker you should drink more.


The catheter tube needs to be kept very clean to avoid infection. Don’t be afraid of touching your catheter. It will not fall out

When you wash yourself, use a separate flannel and towel for this area. Every morning and evening (and after a bowel movement) wash the visible part of the catheter and the area where it enters the body with warm water and soap. Take care not to pull the tube. Rinse and dry.

Avoid scented soap and talcum powder as this can cause irritation. Constipation

Constipation can prevent the catheter from draining freely and can cause leakage around the tube. You can avoid constipation by eating a healthy balanced diet including roughage (wholemeal bread, bran, fresh fruit and vegetables) and drinking plenty of fluids. If you think you may be constipated, please talk to your GP or pharmacist, who will be able to help.


Any of the following signs indicate an infection, contact your GP if you think you have an infection.

  • Fever and chills
  • Abdominal or lower back pain
  • Cloudy, offensive smelling urine
  • Blood in the urine

There are two main types of bag that can be used with your catheter. Leg bags are small and discreet and can be worn under clothing. A larger volume night bag can be attached to the leg bag to provide more capacity overnight. Don’t disconnect the catheter from the bag unless you are changing the bag.

How to empty the bag

  • Wash and dry your hands
  • Open the tap over the toilet or a suitable container and drain the urine.
  • Close the tap and wipe with a dry tissue. Flush the toilet.
  • Wash and dry your hands

How to secure the leg bag

The leg bag can be secured with straps (provided in the packet) or a sleeve pocket which fits over the leg. Both need to be snug enough to prevent the bag from being under tension and pulling, but should not be too constrictive. Additionally, the catheter should be anchored with a strap or adhesive securing device to prevent it from pulling: these can be attached to your abdomen or leg as preferred.


How to change a bag

  • Empty the current bag into the toilet
  • Wash and dry your hands
  • Open the packet with the new bag in it
  • Remove the dust cap from the bag without touching the end of the tubing
  • Pinch the catheter just above the connection to the old bag
  • Disconnect the old bag
  • Push the end of the new bag firmly into the catheter
  • Dispose of the oldbag
  • Wash your hands again

Using a night bag

  • Wash your hands
  • Remove the dust cap from the night bag
  • Push the tubing firmly into the drainage tap of the leg bag
  • Open the drainage tap of your leg bag to allow urine to drain into the night bag
  • Wash your hands again

If you are using a drainable night bag it should be disconnected from your leg bag each morning. Empty it, rinse it under running water and leave to air dry. Replace the dust cap.

Single use, non drainable night bags should be disconnected from the leg bag each morning and emptied prior to disposal.

The leg and night bags should be changed every five to seven days to reduce your risk of getting an infection.

Drainage bags may be disposed of in the dustbin, provided they have been emptied and wrapped in a newspaper or plastic bag for hygiene reasons.

The leg and night bags should be changed every five to seven days to reduce your risk of getting an infection.

Drainage bags may be disposed of in the dustbin, provided they have been emptied and wrapped in a newspaper or plastic bag for hygiene reasons.

Sometimes we may need to leave your catheter in place for some time after you leave hospital. If so, we will tell you all you need to know about caring for your catheter. We will also give you a supply of drainable bags for use at night and during the day.

If appropriate we will refer you to the district nursing service for support at home - check with your nurse before you leave hospital.

What should I do if the catheter falls out?

Do not try to replace the catheter yourself. Contact your district nurse or GP.

What should I do if I see blood in the urine?

Firstly don’t panic! The catheter being pulled accidentally may sometimes cause this. You should increase the amount of fluid you are drinking. It may be a sign of infection so if it persists you should contact your GP.

Why does urine sometimes leak around the catheter?

The catheter or drainage tubing may be blocked, there may be irritation from the catheter, there may be a build up of debris or you may be constipated.

  • Check the catheter and tubing - release any kinks.
  • If you are constipated please follow the earlier advice.
  • Ensure you are drinking enough.
  • Movement may dislodge a minor blockage - so walk around.
  • Medication can sometimes help relieve bladder spasm although it is not suitable for everyone.

What should I do if the catheter does not appear to be draining?

  • Empty the bag and make a note of the time.
  • Check the catheter and tubing - release any kinks.
  • Make sure the bag is positioned below waist level.
  • Ensure you are drinking enough - if drainage does not improve or you become uncomfortably full, contact your GP or district nurse.

Is it possible to have sex with a catheter in place?

Yes - but please follow the steps below

  • Check with your doctor before you leave hospital, especially if you have recently had surgery.
  • Empty the drainage bag.
  • You should tape the catheter to the abdomen; lubricating jelly may make intercourse more comfortable. After intercourse you should wash around the catheter.

How do I get more supplies?

  • You should be provided with a small supply of drainage bags before you go home.
  • You will need a prescription from your doctor for further supplies; you can take this to a pharmacy to be dispensed. Alternatively you may use a home delivery service which will deliver your supplies free of charge: ask your nurse about this.

  • The Multiple Sclerosis Helpline: 0808 800 8000 
  • The Stroke Association: 0845 303 3100
  • Promocon: 0161 834 2001
  • Parkinson’s Disease Society: 0808 800 0303

UCL Hospitals cannot accept responsibility for information provided by external organisations.

If you have any problems or questions about your catheter, please ask one of the nursing team on the ward or your GP/District Nurse for advice.

  • Ward:
  • District Nurse:

Continence Advisory Service

UCH and University College Hospital at Westmoreland Street
Telephone: 020 3447 7995

The National Hospital, Queen Square
Telephone: 020 7829 8713

Womens’ Health at EGA
Telephone: 0845 155 5000 ext 76547
Mobile: 07951 674140

Dougherty L and Lister S (eds) (2004) The Royal Marsden Hospital Manual of Clinical Nursing Procedures. Blackwell Publishing.

University College Hospital at Westmoreland Street


The National Hospital for Neurology and Neurosurgery




Page last updated: 17 May 2024

Review due: 01 November 2024