Flexible Sigmoidoscopy
Flexible sigmoidoscopy is a targeted lower-colon exam that helps evaluate rectal bleeding, inflammation, diarrhea, lower abdominal pain, and symptoms involving the rectum and sigmoid colon. As part of the GastroDoxs GutDefense Pathway™, patients can better understand why this exam may be recommended and how findings may guide follow-up care.
Medically Reviewed by Dr. Bharat Pothuri, MD, FACG | Updated 03-24-2026
What Is Flexible Sigmoidoscopy?
Flexible sigmoidoscopy is a procedure that uses a thin, flexible camera to examine the rectum and lower part of the colon, called the sigmoid colon.
It is more targeted than a full colonoscopy and may be recommended when symptoms appear to involve the lower colon or rectum.
The exam allows your GI doctor to see the lower colon lining directly. If inflammation, ulcers, abnormal tissue, or small polyps are seen, biopsies or treatment may be performed when clinically appropriate.
Understanding Flexible Sigmoidoscopy
The exam allows your GI doctor to see the lower colon lining directly. If inflammation, ulcers, abnormal tissue, or small polyps are seen, biopsies or treatment may be performed when clinically appropriate.
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Why Is Flexible Sigmoidoscopy Done?
A doctor may recommend flexible sigmoidoscopy to evaluate symptoms or findings that may come from the rectum, sigmoid colon, or lower portion of the colon. The exam can help identify bleeding sources in the rectum or lower colon.
Rectal bleeding
Chronic diarrhea
Lower abdominal pain
Inflammation
Polyps
Biopsy
How Gastroenterologists Decide on Flexible Sigmoidoscopy
The decision to recommend Flexible Sigmoidoscopy is based on symptoms, medical history, exam findings, lab results, imaging, prior testing, medication response, and the goal of the evaluation. This helps ensure the procedure or test is clinically appropriate and connected to a clear next step.
What Can Flexible Sigmoidoscopy Help Evaluate?
Flexible sigmoidoscopy can help identify conditions affecting the rectum and lower colon. The exam may show inflammation, ulcers, or irritation in the lower colon or rectum.
Rectal bleeding
Chronic diarrhea
Lower abdominal pain
Inflammation
Polyps
Biopsy
How Results Are Interpreted
Results from Flexible Sigmoidoscopy are reviewed in context with your symptoms, risk factors, prior testing, and clinical history. Your gastroenterologist explains whether results suggest monitoring, treatment, additional testing, or follow-up care.
Flexible Sigmoidoscopy Alternatives and Related Testing
Flexible Sigmoidoscopy may be one part of a broader digestive health evaluation. Depending on the concern, alternatives or related tests may include blood work, stool testing, imaging, endoscopy, ultrasound-based testing, or follow-up monitoring. Your gastroenterologist helps choose the most appropriate option.
Who May Need Flexible Sigmoidoscopy
Your doctor may recommend Flexible Sigmoidoscopy based on symptoms, risk factors, prior test results, or the need for a clearer diagnosis.
Patients with Rectal bleeding
Patients with Chronic diarrhea
Patients with Lower abdominal pain
Patients with Inflammation
Patients with Polyps
Patients with Biopsy
Benefits of Flexible Sigmoidoscopy
Flexible Sigmoidoscopy can provide useful information about digestive or liver health and may help your gastroenterologist plan the next step.
Helps evaluate rectal bleeding
Helps evaluate chronic diarrhea
Helps evaluate lower abdominal pain
Helps evaluate inflammation
Helps evaluate polyps
Helps evaluate biopsy
Possible Risks of Flexible Sigmoidoscopy
Flexible Sigmoidoscopy is generally safe when performed or supervised by trained GI specialists, but every procedure or test has considerations based on your health history, medications, and reason for evaluation.
When Should You Talk to a GI Specialist?
Talk to a gastroenterologist if symptoms persist, results are unclear, or your doctor recommends Flexible Sigmoidoscopy for diagnosis, monitoring, or treatment planning.
Related Flexible Sigmoidoscopy Guides
Use these next-step pages when you are ready to understand preparation, scheduling, or related digestive health topics.
What to Expect
Learn preparation, procedure-day expectations, recovery, and how results may be discussed.
Schedule Flexible Sigmoidoscopy
Review appointment, location, insurance, and scheduling details.
Rectal bleeding
Learn how rectal bleeding may relate to digestive or liver evaluation.
Chronic diarrhea
Learn how chronic diarrhea may relate to digestive or liver evaluation.
Lower abdominal pain
Learn how lower abdominal pain may relate to digestive or liver evaluation.
Inflammation
Learn how inflammation may relate to digestive or liver evaluation.
Flexible Sigmoidoscopy Prep Overview
Quick Answer: What should adults know about Flexible Sigmoidoscopy prep?
Flexible Sigmoidoscopy preparation depends on the reason for the test, the setting, and your health history.
Follow the written instructions from your GastroDoxs care team, including medication guidance, arrival time, and transportation planning when sedation is used.
Flexible Sigmoidoscopy Procedure Instructions
Watch your GastroDoxs procedure instructions before your visit and follow the written preparation guide from your care team.
Where to Learn the Next Step
| Want procedure-day details? | Review the full guide for preparation, procedure-day expectations, recovery, and how results are discussed. Learn more |
| Ready to discuss scheduling? | If Flexible Sigmoidoscopy may be appropriate, use the scheduling page to understand appointment options. Learn more |
Frequently Asked Questions
Answers are reviewed for clinical accuracy based on standard gastroenterology practice guidelines.
What is flexible sigmoidoscopy?
Flexible sigmoidoscopy is a procedure that uses a thin, flexible camera to examine the rectum and lower part of the colon, called the sigmoid colon.
Why would a doctor recommend a flexible sigmoidoscopy?
A doctor may recommend it for rectal bleeding, chronic diarrhea, lower abdominal pain, inflammation, abnormal imaging, abnormal stool tests, or follow-up of known lower-colon disease.
What part of the colon does a flexible sigmoidoscopy examine?
It examines the rectum and sigmoid colon. It does not examine the entire colon, which is why colonoscopy may be recommended when a full evaluation is needed.
How is a flexible sigmoidoscopy different from a colonoscopy?
Flexible sigmoidoscopy checks the lower colon and rectum. Colonoscopy examines the entire colon and can be more appropriate for screening or symptoms that may come from higher in the colon.
I'm seeing blood in my stool — do I need a flexible sigmoidoscopy urgently?
Blood in the stool should be evaluated promptly. Seek emergency care for heavy bleeding, dizziness, weakness, severe pain, or black stools. A GI evaluation can determine whether sigmoidoscopy, colonoscopy, or another test is needed.
Why would you have a sigmoidoscopy instead of a colonoscopy?
Sigmoidoscopy may be used when symptoms appear limited to the rectum or lower colon, when a shorter targeted exam is appropriate, or when the doctor wants to evaluate known lower-colon disease.
How painful is a flexible sigmoidoscopy?
Most patients feel pressure, cramping, or gas rather than severe pain. Sedation needs vary by patient, procedure plan, and medical history.
Do you need bowel prep for sigmoidoscopy?
Yes. Preparation usually focuses on cleaning the lower colon and may include enemas, diet instructions, or other prep steps based on your doctor’s instructions.
Do they put you to sleep for a flexible sigmoidoscopy?
Some flexible sigmoidoscopies are done without full sedation, while others may use sedation for comfort. Your care team will explain the plan before the procedure.
How long does a flexible sigmoidoscopy take?
The exam itself is usually brief, often around 10 to 20 minutes. Total visit time may be longer because of check-in, preparation, recovery, and discharge instructions.