A colonoscopy is an exam that views the inside of the colon (large intestine) and rectum, using a tool called a colonoscope.
The colonoscope has a small camera attached to a flexible tube that can reach the length of the colon.
When You're in the Hospital
This is what the procedure involved:
- You were likely given medicine into a vein (IV) to help you relax. You should not feel any pain.
- The colonoscope was gently inserted through the anus and was carefully moved into the large intestine.
- Air was inserted through the scope to provide a better view.
- Tissue samples (biopsy or polyps) may have been removed using tiny tools inserted through the scope. Photos may have been taken using the camera at the end of the scope.
Right After the Test
You will be taken to an area to recover right after the test. You may wake up there and not remember how you got there.
The nurse will check your blood pressure and pulse. Your IV will be removed.
Your doctor will likely come to talk to you and explain the results of the test.
- Ask to have this information written down, as you may not remember what you were told later on.
- Final results for any tissue biopsies that were done may take up to 1 to 3 weeks.
Medicines you were given can change the way you think and make it harder to remember for the rest of the day.
As a result, it is NOT safe for you to drive a car or find your own way home.
You will not be allowed to leave alone. You will need a friend or family member to take you home.
Eating and Drinking
You will be asked to wait 30 minutes or more before drinking. Try small sips of water first. When you can do this easily, you should begin with small amounts of solid foods.
You may feel a little bloated from air pumped into your colon, and burp or pass gas more often over the day.
If gas and bloating bother you, here are some things you can do:
- Use a heating pad
- Walk around
- Lie on your left side
The Rest of the day
Do not plan to return to work for the rest of the day. It is not safe to drive or handle tools or equipment.
You should also avoid making important work or legal decisions for the rest of the day, even if you believe your thinking is clear.
Keep an eye on the site where the IV fluids and medicines were given. Watch for any redness or swelling.
Ask your doctor which medicines or blood thinners you should start taking again and when to take them.
If you had a polyp removed, your doctor may ask you to avoid lifting and other activities for up to 1 week.
When to Call the Doctor
Contact your health care provider if you have:
- Black, tarry stools
- Red blood in your stool
- Vomiting that will not stop or vomiting blood
- Severe pain or cramps in your belly
- Chest pain
- Blood in your stool for more than 2 bowel movements
- Chills or fever over 101°F (38.3°C)
- No bowel movement for more than 3 to 4 days
Brewington JP, Pope JB. Colonoscopy. In: Fowler GC, ed. Pfenninger and Fowler's Procedures for Primary Care. 4th ed. Philadelphia, PA: Elsevier; 2020:chap 90.
Chu E. Neoplasms of the small and large intestine. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 179.
Review Date 8/8/2023
Updated by: Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.