Colonoscopy at Highgate Hospital

What is a colonoscopy?

A colonoscopy is a test that allows a consultant to look at the inner lining of your large intestine (rectum and colon). We use a thin, flexible tube called a colonoscope to look at the colon.

What are the benefits of a colonoscopy?

A colonoscopy helps identify conditions such as:

• ulcers
• colon polyps
• tumours
• areas of inflammation.

Is a colonoscopy right for me?

A colonoscopy can help to explore possible causes of:

• abdominal pain
• rectal bleeding
• chronic constipation
• chronic diarrhoea
• other intestinal problems.

If you're over 50 your doctor may recommend a colonoscopy every 10 years, or sometimes sooner, to screen for colon cancer. Even if you have no other risk factors, age can increase your risk of getting colon cancer.

If you've had polyps before, a follow-up colonoscopy can find and remove any additional polyps. This is done to reduce your risk of colon cancer.

What happens during a colonoscopy?

Preparing for a colonoscopy

Before a colonoscopy, you'll need to clean out (empty) your colon. If your colon lining isn't clear of solids or liquids, then the colonoscope may not have a clear view of the rectum.

2 days before your colonoscopy - eat a low fibre diet to help keep your colon clear.

The day before your colonoscopy - your doctor will ask you to drink laxative sachets to empty your bowels. You'll probably get diarrhoea a few hours after taking the first sachet, so it's best to be at home all day so that you're close to a toilet.

During a colonoscopy

If appropriate, the endoscopist may offer you a sedative or painkiller. The procedure involves placing a flexible telescope into the back passage and blowing some air into the large bowel to get a clear view.

The endoscopist will be able to look for problems such as inflammation or polyps. They will also be able to perform biopsies and take photographs to help make a diagnosis.

A colonoscopy usually takes 30-45 minutes.