Understanding colonoscopy

What is a colonoscopy? 

A colonoscopy uses a thin, flexible tube to examine the inside of your colon. The colonoscope is carefully passed into your colon via your rectum where the consultant will then be able to look at the inner lining of your large intestine.  

Why might I need a colonoscopy?

A colonoscopy may be necessary for many different reasons.

Checking bowel symptoms which may include:

  • Bleeding from your back passage or blood in your poo
  • Chronic diarrhea
  • Chronic constipation  
  • Anal discharge
  • Itchy anus  
  • Abdominal pain  

While these symptoms may require a colonoscopy, they are often nothing to worry about.  

Checking for growths on your bowels which may include:

  • Growths on your bowels are called polyps  
  • These growths are often nothing to worry about, but they can become cancerous, so we advise you have them checked.
  • The polyps can be removed during the colonoscopy
  • If you have had polyps in the past, a follow-up colonoscopy can find and remove any additional polyps.  

 Bowel conditions identified through a colonoscopy:

  • Crohn's disease  
  • Bowel cancer  
  • Ulcers causing inflammation  
  • Diverticulitis  

 Are there any alternatives to a colonoscopy?

You may be presented with alternatives to a colonoscopy depending on your symptoms.

These may include:

  • Sigmoidoscopy (examines the lining of your sigmoid colon)
  • A virtual colonoscopy (an X-ray examination of the colon using low dose CT)
  • Barium enema (an X-ray of the large intestine).

Your letter will advise you on what you can eat and drink 2 days before the procedure. This often suggests eating plain food such as rice, plain cooked chicken, and eggs.  

The day before your colonoscopy you will be given laxatives to take. These will empty out your bowels so that your consultant has a clear view.

You will experience diarrhea after taking the laxatives so make sure you are near a toilet.  

We understand that this procedure may be daunting for you, but don’t worry our medical staff will carefully look after you.  

  • You may be offered a sedative before the procedure which will be given through a small plastic tube placed in your vein in the back of your hand.
  • The procedure will take 30-45 minutes and uses a lubrication to make it quick and painless. 
  • A thin, flexible tube with a small camera inside will be placed in your anus. Air will then be passed through the tube into your bowels. This is done to make the lining easier to see.
  • You may experience a feeling similar to having trapped wind or may feel you need to toilet. Don’t worry about this, it is very normal and the staff will be expecting it.
  • The endoscopist will then look for problems in your bowels.
  • You may be asked to change positions during the procedure in order to get a better view of different areas of your colon.
  • Any growths (polyps) on your bowels will be removed or samples will be taken if necessary (a biopsy). This will be painless.
  • The colonoscopy is then removed quickly and easily.
  • You will then be safely taken to the recovery room where you will be monitored until you are ready to go home.  

You may feel a bit bloated and experience wind pains after the surgery. These will not last long. 

If a biopsy has been taken or a polyp has been removed then you may experience bleeding from your anus. This is normal so it is nothing to worry about.  

You will be able to return to work the following day. 

If you have any of the following symptoms after surgery please call us straight away and we will help you with the next steps: 

  • Heavy bleeding from your anus
  • A fever or high temperature  
  • Abdominal pains which are getting worse and are ongoing.  

Your consultant or a member of the medical staff will discuss your results with you after the procedure and will advise you on what needs to happen next.  

Normal results 

  • This will mean that there were no polyps on cancer found in your bowels. 
  • If this is the case your doctor will advise you on what to do next, this may just be to come back for a check-up in 5 years' time. 

Growths found on your bowels 

  • If this is the case, your doctor will have tested them and if necessary will have removed them during the procedure  
  • They may suggest you need further treatment or perhaps just a check-up 

Bowel cancer 

  • If your results detect bowel cancer you will immediately be seen by a cancer specialist for treatment as soon as possible.  

 An alternative bowel condition 

  • If this is the case you will be advised for further treatment.

 We will be with you every step of the way, even when you have left the hospital. We will be available to ask any questions or worries you may have. 


Initial consultation From: £150
Treatment £1,855
Pre-assessment Included
Main treatment Included
Post-discharge care Included
Guide price £2,005

*The above prices are guide prices only and subject to change at any given time. Diagnostic scans and investigations are not part of the guide price. The guide price indicates the starting price for the treatment.

The cost of treatment will be made clear to you before you proceed with any tests, scans, consultations, or treatment. Please read our terms and conditions. If you have private medical insurance please follow the guidance here.

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