Flexible sigmoidoscopy is a simple and less invasive procedure used to examine the lower part of the large intestine, including the rectum and sigmoid colon. It's similar to a colonoscopy, but only looks at the left side of the colon, rather than the entire bowel.
Doctors may recommend a sigmoidoscopy when a full colonoscopy isn’t necessary. The procedure is quicker, often doesn’t require a full bowel cleanse, and is usually well tolerated.
Preparation for a flexible sigmoidoscopy is usually easier than for a full colonoscopy. In most cases, you’ll be given a rectal enema shortly before the procedure. This helps clear out the lower bowel so your doctor can get a clear view.
Here’s what to expect:
A small tube is inserted into the rectum to deliver the enema liquid.
You’ll be asked to hold it for a few minutes, then use the toilet to empty your bowel.
You’ll need to be on clear fluids for 24 hours before the procedure and to fast (no food or drink) for at least 4 hours before your appointment.
Most medications can be continued as normal. However:
If you take blood thinners like aspirin, Clopidogrel (Plavix), or Warfarin, you may need to stop them up to a week before the procedure—especially if biopsies are planned.
If you have diabetes, you’ll receive a specific plan for managing your medications around the time of the procedure.
Some blood pressure medications may also need to be adjusted—your doctor will advise you on this during your pre-procedure consultation.
Flexible sigmoidoscopy is a quick and well-tolerated procedure. Sedation is given to the paitent in order to be more relaxed.
During the procedure:
A thin, flexible tube with a camera is gently inserted into the rectum.
The doctor will examine the lower bowel for any signs of inflammation, bleeding, polyps, or other abnormalities.
Some gas may be introduced into the bowel to help with visibility.
The procedure typically takes only a few minutes.
If you haven’t had sedation, you’ll feel back to normal very quickly. You might experience some mild bloating or cramping, and you may pass some gas—this is completely normal.
If you’ve had sedation:
You’ll need to stay for observation until the sedative wears off (usually about an hour).
For the rest of the day, you must not drive, work, drink alcohol, or sign legal documents.
Be sure someone escorts you home and stays with you until the next day.
Your doctor will discuss the findings with you before you leave. A summary report will also be provided, and a detailed report sent to your GP. If any biopsies were taken, your gastroenterologist will follow up once the results are available.
If you have any questions before or after your procedure, don’t hesitate to contact your gastroenterologist. You can also find helpful information on the Gastroenterological Society of Australia website: www.gesa.org.au