Flexible Sigmoidoscopy

What is a flexible sigmoidoscopy?

A flexible sigmoidoscopy is a procedure used to examine the inside of the lower part of the large intestine (rectum and sigmoid colon). It helps investigate symptoms such as:

  • Rectal bleeding or blood in the stool.

  • Changes in bowel habits (diarrhoea).

  • Monitoring inflammatory bowel disease (IBD), such as ulcerative colitis.

The procedure is performed using a sigmoidoscope—a thin, flexible tube with a camera at the tip—that provides a detailed view of the rectum and lower colon. It can also be used to:

  • Take tissue biopsies for further testing.

  • Remove polyps.

  • Stop bleeding.

  • Treat haemorrhoids.

  • Widen narrowed areas of the rectum or distal colon (dilation).

How do I prepare for a flexible sigmoidoscopy?

Bowel preparation

  • Limited bowel preparation is required compared to a full colonoscopy.

  • You will take an enema (where liquid is gently injected into the rectum through a small tube in the anus) to cleanse the rectum and lower colon.

Fasting

  • Do not eat or drink for 6 hours before the procedure.

  • You may have small sips of water up to 2 hours before.

  • Unlike a colonoscopy, no special dietary changes are required before the procedure.

Medications

  • If you take blood thinners or diabetes medications, I will provide specific instructions on how to manage them before the procedure.

  • Otherwise, take your regular medications with a sip of water up until 2 hours before the procedure.

What happens on the day of the procedure?

  • Arrive at The San at the time advised by the hospital staff (they will call the day before).

  • The nursing team will check you in and prepare you for the procedure.

  • The sedation will ensure you are asleep and comfortable during the procedure. However, some patients may have the procedure with minimal or no sedation.

How long does it take?

  • The procedure itself takes about 10 to 20 minutes.

  • Plan to be at the hospital for 2 to 3 hours to allow time for check-in, preparation, and recovery.

What happens after the procedure?

  • You will be taken to the recovery area until the sedation wears off.

  • Most patients can eat and drink soon after waking up.

  • You may experience mild cramping, which should settle quickly.

  • Once fully awake, I will discuss the findings with you and provide a written report.

  • Any important biopsy results and follow-up care will be discussed at a later appointment, either in person or via phone.

Important information about sedation

If sedation is used, your reflexes, coordination, and decision-making will be affected for 24 hours. For your safety:

✅ You must be accompanied home by a responsible adult.
❌ Do NOT drive any vehicle.
❌ Do NOT operate machinery or cook.
❌ Do NOT sign legal documents or make important decisions.
❌ Do NOT drink alcohol, take recreational drugs, or smoke.
❌ Ensure an adult stays with you overnight.