A colonoscopy is an examination of the lining of the large bowel (bowel) using a thin flexible, tube-like telescope called a colonoscope, which is carefully passed through your back passage and into the colon. It is useful for finding out what is causing certain symptoms like abdominal pain, or as a check-up for some bowel conditions.
Your doctor may recommend you have a colonoscopy if you experience symptoms such as changes to your bowel habits, anal discharge, itchy anus, bowel incontinence, constipation, diarrhoea or bleeding from your back passage. It can be used to help diagnose bowel cancer and as a check-up on certain bowel conditions, like Crohn's disease.
During the procedure, your doctor may take one or more biopsies (samples of the lining of the colon) for examination in a laboratory. It’s also possible to remove polyps (small lumps of tissue that may be found on the colon lining) at the same time. Though polyps are harmless, they have the potential to become cancerous.
Depending on your symptoms, alternatives to this procedure may include a sigmoidoscopy, a virtual colonoscopy or a barium enema.
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You will have a formal consultation with a healthcare professional. During this time you will be able to explain your medical history, symptoms and raise any concerns that you might have.
We will also discuss with you whether any further diagnostic tests, such as scans or blood tests, are needed. Any additional costs will be discussed before further tests are carried out.
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Our dedicated team will also give you tailored advice to follow in the run up to your visit.
We understand that having an examination can potentially be a time of anxiety and worry. Our experienced and caring medical staff will be there for you, holding your hand, every step of the way.
A colonoscopy is usually performed under sedation to help ensure that you are relaxed and comfortable during the procedure. After sedation, most people have very little memory of the test. The procedure takes up to 30 minutes and you may be a bit uncomfortable.
If you're having sedation, this may be given through a small plastic tube (cannula) placed in a vein in the back of your hand. You may need oxygen through a mask during the procedure and for a short time afterwards. While you rest on your side, your doctor will examine your back passage with a finger before carefully inserting the colonoscope. He or she will use lubricating jelly to make this as easy as possible.
Air will be passed through the tube and into your colon to make the lining easier to see. When this happens, you may briefly feel pains similar to trapped wind. You may also feel that you want to go to the toilet, but as the colon is empty, this will not be possible. Try not to feel embarrassed if you pass wind, as the staff expect this to happen.
A tiny light and lens at the end of the colonoscope allow your doctor to see the lining of your colon. They may do this by looking directly through the colonoscope, or at pictures it sends to a video screen.
You may be asked to change your position during the procedure, for example turning from your side onto your back. This helps your doctor to examine different areas of your colon with the colonoscope more easily.
If necessary, they will take a small biopsy for analysis and remove any polyps that can be found. This is done using special instruments passed inside the colonoscope, and is quick and painless.
Afterwards, the colonoscope is removed quickly and easily.
A colonoscopy is routinely done as an out-patient or day-case procedure, so you will not need to stay overnight in hospital. After the procedure, you will be taken to your own recovery room where you can relax in comfort until you’re up to going home - generally half an hour. The nursing staff will be on hand to make sure you are comfortable. If you have had a sedative, you may doze off.
If you have had a biopsy or any polyps removed, the results will be ready several days later and will usually be sent into the doctor who recommended the test. Other findings can be discussed before you leave the hospital. If you have had sedation, it’s a good idea to have someone with you when you are told the results, as you may not remember the details clearly.
After the examination, you may feel bloated and have wind pains, but these usually clear up quite quickly. The sedative may make you feel sleepy. If a biopsy has been taken or a polyp has been removed, you may experience a small amount of bleeding from your back passage after the procedure.
Occasionally, a colonoscopy is not completed successfully and may need to be repeated.
Once you’re ready to be discharged from hospital, you’ll need to arrange a taxi, friend or family member to take you home as you won’t be able to drive. You should arrange for someone to stay with you for the first 24 hours.
Even after you’ve left hospital, we’re still looking after you every step of the way.
On rare occasions, complications following a colonoscopy can occur. If you experience any of these symptoms please call us straight away.
This could be the result of your colon being damaged or, in very rare cases, perforated during the procedure.
The chance of complications depends on the exact type of procedure you are having and other factors such as your general health. We will talk to you about the possible risks and complications of having this procedure and how they apply to you.
If you have any questions or concerns, we're here to help.
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The treatment described on this page may be adapted to meet your individual needs, so it's important to follow your healthcare professional's advice and raise any questions that you may have with them.
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