Colonoscopy is a procedure that utilizes a flexible tube with light and camera at the end (endoscope or colonoscope) to look at the inner lining of a person’s large intestine (colon) through a video monitor.

Colonoscopy is recommended for the following reasons:

  1. Screen for colorectal cancer.
  2. Blood in the stool.
  3. Change in bowel habits (constipation or diarrhea).
  4. Abdominal pain.
  5. Abnormal tests like CT scan, X-ray, or stool test.
  6. Unexplained iron deficiency anemia.
  7. History of colon cancer or polyps.
  8. Management of inflammatory bowel disease (ulcerative colitis or Crohn’s disease).


Before your colonoscopy

 My colonoscopy is tomorrow. What should I expect

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Before your colonoscopy, you will need to prepare your bowel for the procedure. This is called bowel preparation. The process of bowel preparation often begins up to a week before the scheduled procedure and involves stoppage or adjustment of medications such as anticoagulants. It often requires a change in diet a day or more before the colonoscopy and consumption of a bowel cleansing agent. For tips on how to make your colonoscopy preparation more tolerable, read 10 Tips for Making Colonoscopy Preparation More Tolerable.

Before the procedure, your doctor will go over the procedure with you, explaining the risks, benefits and alternatives. This is called the consent. You will sign a consent form after all your questions have been answered.


During your colonoscopy

My colonoscopy is tomorrow. What should I expect

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During your colonoscopy, your doctor will give you medications to make you feel relaxed, drowsy, or asleep during the procedure. This is called sedation. The level of sedation depends on your health conditions, preference, and the practice pattern of your doctor. It should be noted that colonoscopy may be performed without sedation. After sedation, your doctor will insert the lubricated tip of the colonoscope into your anus and then using dials and fine movements navigate the colonoscope up into the rectum, colon, and sometimes the terminal ileum. Looking at a video monitor, your doctor will examine the innermost lining of your bowel.

During the procedure, your doctor has the ability to take a small piece of tissue from the colon (biopsy), remove a polyp (polypectomy), mark a specific spot (tattoo), treat a blockage, or stop bleeding (hemostasis).


After your colonoscopy

My colonoscopy is tomorrow. What should I expect.

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After your colonoscopy, you will be taken to a room where you will be monitored until you wake up. This is called recovery. You may eat after you are awake. You may experience abdominal discomfort and bloating after the procedure. This is mostly due to the air used to distend the colon for easy viewing. Passing gas may help relieve the discomfort. Most doctors recommend that you do not operate machinery or work for the rest of the day. An adult relative or friend will be responsible for taking you home. You will be given instructions on when to resume your medications. Instructions on when to call your doctor or provider will be provided. Call your doctor or provider if you have any of the following problems after your colonoscopy:

  • Severe abdominal pain
  • Persistent nausea and vomiting
  • Distended and tense abdomen
  • Large rectal bleeding
  • Fever


If a small piece of tissue is taken from your colon (biopsy) or a polyp is removed (polypectomy), your doctor will give you the results after a few days. It may take up to a week or more for some special studies to come back.

What happens before, during, and after your colonoscopy varies depending on your condition and your doctor’s practice. Please, talk to your doctor about your colonoscopy.

Things People Say After a Colonoscopy

  • My colonoscopy was easier than I thought.
  • The most unpleasant aspect of my colonoscopy was the prep.
  • My colonoscopy was shorter than I thought.
  • I feel bloated and gassy after my colonoscopy otherwise it was okay.

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