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Flexible sigmoidoscopy

Equipment used to carry out endoscopy.

Flexible sigmoidoscopy

A flexible sigmoidoscopy is an examination of the left half of your large bowel (otherwise known as the large intestine or the colon).

It is performed using an instrument called a flexible sigmoidoscope or its longer counterpart, the colonoscope. This is a long, thin, flexible tube with a light and a camera at one end. The camera sends images of the inside of your body to a television screen.

During the investigation, the endoscopist may need to take some tissue samples, known as biopsies, from the lining of your large bowel for further analysis. This is completely painless. Photographs may also be taken for your medical records.

There are several reasons why this test may be recommended, and your doctor will discuss these with you. Common indications include:

  • A change in your usual bowel habit to constipation or diarrhoea.
  • Bleeding from the back passage.
  • A review of a known bowel condition (e.g., inflammatory bowel disease, colonic polyps).
  • To assess or treat an abnormality seen on other tests such as barium enema or CT scan.

If none of these apply to you, your doctor will explain any other reasons there may be for having this test.

The procedure usually takes about 10 minutes, but this can vary depending on how many twists there are in your bowel, and whether any additional procedures are required.

Flexible sigmoidoscopy is a short test, and most people will remain comfortable without sedative drugs or pain killers. If you are particularly anxious about the test discuss this with your team and it may be possible to provide you with intravenous sedation or gas.

While you are waiting for your sigmoidoscopy, ensure you maintain a healthy diet, reduce alcohol, and consider stopping smoking. Try and avoid being too constipated by taking laxatives regularly if needed. This will also help to ensure that your bowel is fully emptied when you take the bowel preparation before the procedure. Avoid any foods that make your bowel symptoms worse.

It is extremely important that the left side of your bowel is completely empty before a flexible sigmoidoscopy to allow adequate inspection of the lining of your colon.

Once your sigmoidoscopy is scheduled, the hospital will send you instructions for how to prepare. This is usually achieved by giving you a bowel cleansing laxative to take at home on the day before your procedure. Sometimes, an enema on the day of the test is all that is required, you will be informed if this is the case. If you are taking iron tablets, then stop these 7 days before the test.

It is very important to follow the instructions on the letter from the hospital.

What should you do if your health is deteriorating?

If you develop new symptoms such as blood mixed in your stools, severe pain, not passing stools or wind, or rapid weight loss then contact your GP or specialist as you may need a more urgent review. Equally, if you have existing symptoms that have changed in nature or deteriorated quickly then you should seek further advice and reassessment.

If your appointment has come through but your condition is getting worse, you should contact the hospital team or Patient Advice and Liaison Service (PALS). The number and email for this should be on the hospital appointment letter.

If you haven’t yet received your hospital appointment and your condition is getting worse, you should contact your GP practice. Your GP cannot get you seen quicker at the hospital as they don’t have access to the waiting list or appointment system.

However, if your condition is getting worse or if you are experiencing new symptoms they can assess the situation, give you some advice and may be able to update your specialist to consider upgrading your procedure.

Alternatively, the NHS 111 service is available if you have a medical problem and aren’t sure what to do. To access NHS 111, visit 111 online or call 111. The service operates 24 hours a day, 7 days a week.

BSL users can use the NHS video interpreter service.

Last Updated: 12 April 2024

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