A colonoscopy inspects the inside of the colon with a flexible endoscope, under light sedation. It is both diagnostic and therapeutic: it finds and removes polyps in the same session, preventing cancer. Good preparation is decisive.
What is a colonoscopy?
It is the endoscopic inspection of the colon with a flexible camera-tube. It allows biopsies and polyp removal (polypectomy) in the same examination.
When is it needed?
It is indicated for screening (typically from age 45), for symptoms (bleeding, changed habits, anaemia), for surveillance after polyps or cancer, and for polyp removal.
Preparation
A bowel cleanse with a special (low-residue) diet and a laxative solution beforehand is required. The quality of preparation determines the reliability of the examination. Certain medications (e.g. anticoagulants) are adjusted.
How it's done
Under light sedation, the endoscope is advanced and the mucosa carefully inspected. Where needed, biopsies are taken or polyps removed. The examination usually takes 20–40 minutes.
Screening
Screening in asymptomatic people (typically from age 45) for early detection and prevention.
Diagnostic
For symptoms (bleeding, anaemia, changed habits) for investigation and biopsies.
Polypectomy
Removal of polyps in the same session — interrupts progression to cancer.
Recovery
Once the sedation wears off, the patient goes home the same day (with a companion because of the sedation). Normal activity usually resumes the next day.
Risks & outcomes
It is a safe examination with a very low complication rate. Rare complications (bleeding, perforation) relate mainly to polypectomy and are managed. The benefit in cancer prevention is well established.
Frequently asked questions
Does a colonoscopy hurt?
It is done under light sedation, so the patient is comfortable and pain-free. Most people do not remember the examination.
Why is preparation so important?
A well-cleansed bowel allows safe and reliable inspection. Inadequate preparation can 'hide' lesions and require a repeat.
Are polyps removed straight away?
Yes, in most cases polyps are removed in the same session, which prevents their progression to cancer.
When should I have my first colonoscopy?
Screening typically starts at 45, or earlier with a family history or symptoms. The timing is individualised.