Flexible Sigmoidoscopy or Colonoscopy: What Differs?

If your referral names flexible sigmoidoscopy, you may wonder why someone else with bowel symptoms was offered a colonoscopy. Ask what your clinician needs to examine and why that test fits your assessment. The name alone does not tell you the whole plan.

Compare the same parts of the appointment

Dimension12	Flexible sigmoidoscopy	Colonoscopy
Area examined	Rectum and lower colon.	Rectum and the entire colon.
Preparation	Often less bowel preparation; follow the clinic’s written plan.	Bowel preparation with diet and timing instructions from the clinic.
Sedation	Typically not needed; confirm your own arrangement.	Sedatives or anesthesia are used; arrange the instructed ride home.
Samples	Polyps may be removed and tissue sampled.	Polyps may be removed and tissue sampled.
What can follow	Findings may lead to colonoscopy to examine the rest of the colon.	Sample results and findings guide the next discussion.

Use this comparison to ask about your appointment, rather than choosing a procedure from a table. Bring the referral and say: “Which part of the bowel do you need to examine, and what would make another test necessary?”

Confirm your preparation and travel plan

Tell the team about health conditions and all medicines, vitamins and supplements. Both procedures need bowel preparation instructions. Contact the team if side effects stop you completing the prescribed preparation.¹²

Ask them to mark the food, drink and preparation times on your own instructions. If you have two sheets that disagree, call before following either. Have them explain any medicine changes; do not decide these from another person’s appointment advice.

Confirm whether you will receive sedation and what the clinic requires for travel and support afterward. Ask your chosen driver to check the appointment time with you before prep day.

Ask how the results will reach you

Tissue samples need laboratory examination, so their results may arrive after the initial procedure discussion. Ask who will explain both sets of findings and when to contact them if you have not heard.¹²

Write down the agreed contact date and number. At follow-up, ask what was examined, whether samples were taken and what the findings change about your plan.

Get help for concerning symptoms afterward

Seek care right away for severe abdominal pain, fever, ongoing bleeding or bloody bowel movements that do not improve, dizziness or weakness after either procedure. After flexible sigmoidoscopy, severe bloating or vomiting also needs prompt care.¹²

Follow the clinic’s discharge directions and use its urgent contact instructions. Do not wait for a planned results appointment when these symptoms occur.

Bloated by Dinner includes a Test It section for preparing questions about tests. Keep those questions alongside your referral, procedure instructions and agreed follow-up contact.