Colonoscopy — endoscopic examination of the large intestine

What is a colonoscopy?

Colonoscopy — also called an endoscopic examination of the large intestine — is an endoscopic investigation in which a flexible colonoscope is passed via the rectum up through the entire large intestine and, if needed, a short distance into the lower small intestine. The camera provides a detailed view of the mucosa, and during the same procedure the doctor can remove polyps, take tissue samples and stop minor bleeding.

Colonoscopy is a key method for investigating blood in the stool, chronic diarrhoea, iron-deficiency anaemia, inflammatory bowel disease (Crohn's disease/ulcerative colitis), and for detecting and preventing colorectal cancer through polyp removal.

When is colonoscopy indicated?

• Visible blood in the stool
• Positive stool test (FIT/occult blood)
• Persistent diarrhoea or altered bowel habits
• Unexplained iron-deficiency anaemia or weight loss
• Suspected Crohn's disease or ulcerative colitis
• Polyp surveillance and screening in families with colorectal cancer
• Persistent abdominal pain, as part of an individual assessment

Persistent abdominal pain alone does not automatically lead to a colonoscopy. The indication is individual and is based on an overall assessment of symptoms, medical history, age, any alarm symptoms and the results of other investigations.

Black, tarry stools can be a sign of bleeding from the upper gastrointestinal tract and should be assessed promptly by a doctor. In the event of acute illness, dizziness, fainting or significant bleeding, you should contact emergency medical services — this is not a condition to be investigated by a planned private colonoscopy.

How the procedure works

The procedure typically takes 20-40 minutes. You can choose sedation so you are relaxed and often do not remember the procedure itself.^[3] Many smaller polyps can be removed during the procedure, but not all polyps can be removed on the same day. Larger or technically complex polyps may require a separately planned procedure or referral.^[2] Removed polyps are always sent for microscopy. After intravenous sedation you must always: not drive a car or bicycle, operate machinery, drink alcohol or make legally binding decisions for 24 hours. Always follow the clinic's specific instructions.

Preparation (bowel cleansing)

Always follow the bowel preparation instructions you are given. A split-dose regimen usually gives the best cleansing, but preparation is adjusted individually.^[1] The final part is taken close to the procedure and normally completed at least two hours before. Dietary advice can be adjusted individually.

• Blood-thinning medication is adjusted in consultation with the doctor before the procedure. Blood-thinning medication must never be stopped without specific individual instructions from your doctor.

Thorough bowel cleansing is essential to the quality of the examination — you will receive a detailed plan when you book.

Biopsies when microscopic colitis is suspected

If microscopic colitis is suspected, biopsies may be relevant even when the mucosa looks macroscopically normal during the examination itself, as the diagnosis can only be made through microscopic examination of the tissue.

Safety and side effects

Colonoscopy is a well-established and safe procedure. Mild bloating afterwards resolves within a few hours. Perforation at a diagnostic colonoscopy is rare and generally occurs in fewer than 1 in 1,000. Bleeding is unusual with a purely diagnostic examination but occurs more often after polyp removal.^[2] The risk depends, among other things, on the size and location of the polyp, the treatment technique and blood-thinning medication. Your individual risk is discussed before the procedure.

Acute warning signs after the examination

Seek urgent medical help immediately for the following symptoms after a colonoscopy:

• Increasing, severe abdominal pain
• Fever
• Persistent or significant bleeding from the rectum
• Dizziness or fainting
• Persistent vomiting
• General, marked deterioration in your condition

Follow-up after polyp removal

The need for a repeat colonoscopy depends on the quality of the examination, whether the entire colon was examined, and the number, size and microscopic type of any polyps. Some patients need no endoscopic follow-up, while others are advised to have follow-up after, for example, 10 years, 3 years, or sooner after removal of large or complex polyps. The final interval is set according to current guidelines and the pathology report.^[2]

Private colonoscopy at EndoCap

At EndoCap you can book a colonoscopy directly — without a referral from your GP. The clinic is led by a consultant surgeon who performs the procedure, removes any polyps and plans further treatment or follow-up. Some findings may require onward referral to hospital or another relevant specialty. A written report is sent as soon as possible.

This page provides general patient information and does not replace an individual medical assessment, diagnosis or recommendation. Your specific situation is reviewed at consultation.

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