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A colonoscopy is a test performed to investigate the cause of your bowel symptoms. This test can help diagnose many conditions, including IBS (irritable bowel syndrome), Crohn’s disease, IBD (inflammatory bowel disease) and bowel cancer.

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What is a colonoscopy?

During a colonoscopy, a thin tube with a tiny light and camera attached is passed into your bottom and up into your bowel, so your doctor can take a close look.
A colonoscopy might be recommended if you’re exhibiting symptoms such as:

  • Bleeding from your bottom or blood in your poo
  • Changes in bowel habits
  • Chronic constipation
  • Chronic diarrhoea
  • Stomach pain
  • Struggling to pass gas
  • Unexplained weight loss or fatigue


Many people will see a GP first. To rule out more serious conditions such as bowel cancer, a GP will usually recommend a FIT (Faecal Immunochemical Test), which looks for tiny traces of blood in your poo and may also then refer you to a specialist GI or colorectal doctor.

However, if you are worried about your bowel symptoms and would like to see a specialist straight away, you can call our hospital directly and we will book you in with one of our specialist colorectal or GI consultants.

During this appointment, your doctor will ask you about your symptoms, any test results, and take a detailed medical history. After this, they will talk through your options and let you know whether you should have additional tests, such as blood tests, poo samples or a colonoscopy.

You should also tell your doctor if you are taking any medications — especially for diabetes, high blood pressure or heart problems, take medications or supplements that contain iron, or are on blood thinners, such as warfarin or aspirin, as you may need to adjust your dosages or stop taking the medications temporarily ahead of your colonoscopy.

If you decide to have a colonoscopy, a few days before, our Pre-Assessment team will give you a call to explain what will happen on the day and answer any questions you may have.

Preparing for your colonoscopy

Before a colonoscopy, you need to completely clear your bowel as any residue will make it difficult to clearly see your bowel and rectum during the procedure. As such, you will need to eat a low fibre diet for a couple of days beforehand and take a strong laxative the day before.

  • Seven days before. Stop taking certain supplements, such as iron or charcoal tablets.
  • Two days before. Start eating a low fibre diet. This can include foods such as plain steamed chicken with no sauce, white rice, pasta or bread and clear soup. For a more detailed diet sheet SEE HERE
  • The day before. Start taking the laxative (bowel prep) the doctor prescribed. You should follow the doctor’s bowel prep instructions closely; if your bowel is not completely clear, your doctor may not be able to perform the colonoscopy. Once you start drinking the laxative, you should not eat anything. The laxative will usually start working within a few hours and you will need to use the toilet frequently. Use wet wipes and a barrier cream to help reduce soreness and keep a phone or book with you to pass the time. It’s easy to become dehydrated when going to the loo so often and this can make you feel cold, so drink plenty of fluids and wrap up warm.
  • Three hours before your appointment, stop drinking.

Once you arrive at our hospital, we will show you to your room and you can get changed. Don’t forget to bring any prescription medications with you! Your doctor will check that you’re still happy to go ahead with the procedure.


A colonoscopy only takes around 30-45 minutes; it is often defined as an outpatient or day case procedure. This means you will be able to go home the same day.

We highly recommend being sedated for the procedure. You will still be awake, but you should feel less pain and be more relaxed. Once you are comfortable, your doctor will start the colonoscopy. This will usually start with you lying on your left side hugging your knees.

The colonoscope (a long flexible tube with a light and camera) will be passed into your bottom. The doctor will then pump air into the large bowel to open it up. This will make the lining easier to see and facilitate the examination. However, it can feel uncomfortable.

The colonoscope will then be passed through your bowel and the camera will send video to a screen, so your doctor can inspect the health of your large bowel and see if there are any areas that need a closer look. If your doctor notices polyps (benign growths), they will be able to remove them during the procedure. A colonoscopy can be uncomfortable even with sedation but passing air can help reduce the discomfort.


After the colonoscopy, our nurses will take you back to your room and make sure you are ok. You will feel bloated so try to pass as much wind as possible!

Our catering team will also bring you a meal, as you will be very hungry. Once you’re settled, we’ll give you a procedure report and your doctor will inform you of the next steps.

When you’re ready to go home, you should be picked up and looked after for the next 24 hours, while the sedation wears off. During this time you should not drink alcohol, cook or make important decisions.

If you have cramps when you get home, don’t worry – this is very normal. You may also feel a bit groggy and see some blood in your poo for a few days after.

While you’re in recovery, look after yourself. If you develop any of the following symptoms, contact your doctor or our hospital and we will be able to help you:

  • Severe tummy pain
  • A high temperature
  • Vomiting
  • Bleeding from the back passage
  • Unable to eat solid food
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How to pay for your treatment

If you’re… paying for yourself

Did you know you don’t need private medical insurance to come to St John & St Elizabeth Hospital? As a self-pay patient, you can access safe, outstanding quality health care at times to suit you.

For scans and tests, as well as to see most consultants, you’ll still need to be referred by a medical professional like your GP, but as a self-pay patient, the process is more straightforward. You won’t need authorisation from an insurance provider, and you’ll have greater choice of consultant and appointment times.

If you’re… insured

St John & St Elizabeth Hospital is approved by all major medical insurance companies. If you have a personal private health insurance policy, or your company provide it for you, you can use it to pay for your care from your initial consultation through to treatment, surgery and aftercare such as physiotherapy. Not all private health insurance plans cover the same things. It’s very important to check exactly what you are covered for with your insurance provider.