Loading icon
Press enter or spacebar to select a desired language.
Health Information Center

Flexible Sigmoidoscopy

  • Amy Scholten, MPH
Publication Type:


Flexible Sigmoidoscopy
To see an animated version of this procedure, click Procedure InMotion .


A flexible sigmoidoscopy is an exam of the rectum and lower colon (large intestine). The exam is done with a thin tube called a scope. The scope has a tiny camera on the end. It allows the doctor to see inside the rectum and colon.


Nucleus factsheet imagehttp://services.epnet.com/getimage.aspx?imageiid=74067406si55551786.jpgsi55551786.jpgNULLjpgsi55551786.jpgNULL\\hgfiler01a\intellect\images\si55551786.jpgNULL10NULL2008-11-07254390Copyright © Nucleus Medical Media, Inc.

Reasons for Procedure

Flexible sigmoidoscopy is used to look for and treat problems in the rectum and lower colon. The most common reasons for the procedure are to:

  • Take tissue samples for testing—known as a biopsy
  • Look for the cause of lower belly pain, bleeding, or problems with passing stool
  • Look for and remove colon polyps —some polyps can become cancer
  • See if treatment for inflammatory bowel disease is working
  • Screen for colon and rectal cancers

Possible Complications

Problems are rare, but all procedures have some risk. The doctor will go over some problems that could happen, such as:

Things that may raise the risk of problems are:

  • Smoking
  • Drinking alcohol
  • Past surgery or radiation therapy to the area
  • Long term health issues such as diabetes or obesity

What to Expect

Problems to Look Out For

Call your doctor if you have:

  • Increased bleeding from the rectum
  • Black, tarry stools
  • Severe belly pain
  • Hard, swollen belly
  • Signs of infection, such as fever or chills
  • Nausea and vomiting
  • Problems passing gas or stool
  • Chest pain or trouble breathing

If you think you have an emergency, call for medical help right away.





  • Flexible sigmoidoscopy for colorectal cancer screening. EBSCO DynaMed website. Available at: https://www.dynamed.com/prevention/flexible-sigmoidoscopy-for-colorectal-cancer-screening.
  • Flexible sigmoidoscopy. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/diagnostic-tests/flexible-sigmoidoscopy.
  • Ko, C.W., Doria-Rose, V.P., et al. Screening flexible sigmoidoscopy versus colonoscopy for reduction of colorectal cancer mortality. International Journal of Colorectal Disease, 2019; 34 (7): 1273-1281.
  • Understanding flexible sigmoidoscopy. American Society for Gastrointestinal Endoscopy website. Available at: https://www.asge.org/list-pages/patient-informations/understanding-flexible-sigmoidoscopy.


  • Chelsea Skucek, MSN, BS, RNC-NIC
Last Updated:

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.