Colonoscopy is a procedure that lets your doctor look inside your entire large intestine. It uses an instrument called a colonoscope, or scope for short. Scopes have a tiny camera attached to a long, thin tube. The procedure lets your doctor see things such as inflamed tissue, abnormal growths, and ulcers.
Your doctor may recommend a colonoscopy:
- To look for early signs of cancer in the colon and rectum. It may be part of a routine screening, which usually starts at age 50.
- To look for causes of unexplained changes in bowel habits
- To evaluate symptoms like abdominal pain, rectal bleeding, and weight loss
Your doctor can also remove polyps from your colon during a colonoscopy.
You need to be on a clear liquid diet for 1 to 3 days before the colonoscopy. During the procedure, you receive medicines to keep you relaxed.
NIH: National Institute of Diabetes and Digestive and Kidney Diseases
- The Doctor Who Does Your Colonoscopy Matters (06/16/2015, HealthDay)
- Too Few Younger, High-Risk Americans Get a Colonoscopy (05/21/2015, HealthDay)
- Many Americans Not Getting Routine Cancer Screenings: CDC (05/07/2015, HealthDay)
- Colonoscopy: When You Need It -- and When You Don't (ABIM Foundation)
- Your Doctor Has Ordered a Colonoscopy: What Questions Should You Ask? (American College of Gastroenterology) - PDF
- CT Colonography (Virtual Colonoscopy) (Radiological Society of North America, American College of Radiology) Available in Spanish
- Flexible Sigmoidoscopy (National Institute of Diabetes and Digestive and Kidney Diseases) Available in Spanish
- Frequently Asked Questions about Colonoscopy and Sigmoidoscopy (American Cancer Society)
- Understanding Bowel Preparation (American Society for Gastrointestinal Endoscopy)
- Virtual Colonoscopy (National Cancer Institute)
- Virtual Colonoscopy (American College of Radiology)
Statistics and Research
- CDC Vital Signs: Colorectal Cancer (Centers for Disease Control and Prevention)
- CDC Vital Signs: Colorectal Cancer Tests Save Lives (Centers for Disease Control and Prevention) Available in Spanish
Journal ArticlesReferences and abstracts from MEDLINE/PubMed (National Library of Medicine)
Find an Expert
- American Society for Gastrointestinal Endoscopy
- ASGE: Find a Doctor (American Society for Gastrointestinal Endoscopy)
- National Institute of Diabetes and Digestive and Kidney Diseases