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Colonoscopy

What is a Colonoscopy?

Illustration depicting a colonoscopy procedure.
A colonoscope inserted through the
anus and rectum and into the colon.
  • a medical procedure that allows the physician to see inside your large intestine (rectum and colon)
  • uses a long narrow flexible tube called a colonoscope that contains a tiny light and camera at one end
  • camera transmits images (such as swellings, tumors or polyps) to a video monitor in the procedure room
  • using the colonoscope, physician can also biopsy (remove) tissue samples for lab analysis, as well as treat some lesions

How Do I Prepare?

Make sure you understand what is being recommended and what is involved.

Tell your physician if you:

  • have any allergies, heart or lung problems
  • are or think you may be pregnant
  • have had an endoscopy in the past and if you had problems with the medicines
  • take antibiotics before having dental work
  • take medicine to thin your blood (e.g. Coumadin or aspirin compounds). They may need to be stopped for a few days
  • are a diabetic. You will probably need to adjust your insulin or pills.

Do not eat or drink for six hours before your test. Your stomach must be empty (but you can take blood pressure and heart medicines as usual the morning of your test, with a few sips of water). Do not take any antacids.

Your colon must be completely clean for a good test. You will be given detailed instructions, and a special cleansing medicine to take. The colon is better prepared if you take only clear liquids on the day before your colonoscopy. Avoid anything red or carbonated, and avoid dairy products and iron preparations.

Be sure to bring with you:

  • all prescription and over-the-counter medicines you are taking.
  • medical records that relate to your current problem.

Make sure an adult can take you home. The medicines used during the procedure will not wear off for several hours. You will NOT be able to drive. If you travel by public transportation, you will still need an adult to ride home with you.

If you come alone, your test will have to be rescheduled.

What Will Happen?

  1. The nurse and doctor will talk to you about the test and answer any questions you have. You should know why you are having a colonoscopy and understand the treatment options and possible risks. You will be asked to sign a consent form, which gives the doctor your permission to do the test, and any necessary treatment.
  2. You will put on a hospital gown. An IV will be started and blood may be drawn for lab studies. You may receive antibiotics through the IV at this time.
  3. You will be taken by stretcher to the procedure room. The nurse will help you get into the correct position, usually on your side, and make you comfortable. A clip on your finger and a cuff on your arm will help the nurse monitor your pulse, blood pressure and oxygen level.
  4. You will be given medicine through the IV to make you relaxed and sleepy.
  5. When you are sleepy, the doctor will do a rectal examination to check for any problems.
  6. The doctor will then insert the thin colonoscope into your rectum and gently move it up through your colon. The doctor will add air to your colon which opens it up and makes viewing easier. The air may cause a feeling of pressure or cramping.
  7. When the colonoscope reaches the end of the colon where it meets the small intestine, the physician will remove it slowly and gently, looking at the lining of the colon for any problems.
  8. If the doctor thinks that an area of the lining needs to be looked at more closely, a small piece (biopsy) can be removed and sent to the laboratory.
  9. Treatments can be performed during the colonoscopy; details are given below.
  10. The colonoscopy will last between 15 and 45 minutes.

Treatments During Colonoscopy

Cauterization — Areas of bleeding can be controlled by applying medicines through the endoscope directly onto any area of bleeding. The physician can also insert a small heated wire through the colonoscope to seal off blood vessels. You will not feel this treatment.

Polyp removal — Polyps are small growths on the colon lining which can vary in size from a small dot to several inches. Most are noncancerous, but some can grow and become cancerous if left for years. For this reason, polyps are removed during colonoscopy, and sent to the laboratory for further analysis. This is an important way of preventing colon cancer. You will not feel this treatment.

What Will Happen Afterwards?

  1. You will be taken on a stretcher to the recovery area to relax. Your blood pressure and heart rate are watched while you rest. You will be fully awake in about 30 minutes.
  2. After removing your IV, the nurse will give you written instructions to follow when you go home. If you have any questions, please ask. The doctor will talk to you about your test and treatments before you leave. You may have some cramping or bloating because of the air placed in your intestine during the examination. This should go away with the passage of gas (flatus).
  3. Even if you feel awake, your judgment and reflexes will be slow. You will not be allowed to leave unless an adult takes you home. You will NOT be able to drive.
  4. If treatments were done during your test, you may need to be observed overnight so the doctors can check on you.
  5. If specimens (biopsies) were taken during colonoscopy, the results of laboratory analysis will be available in 2 - 3 days.

For the Rest of the Day

  • You should rest quietly
  • Do not drive, operate machinery, sign legal documents or make important decisions.
  • Do not drink alcohol or take sleeping or nerve pills.
  • Drink plenty of fluids. Return to your normal diet and medications unless otherwise instructed.
  • You may feel bloated and pass gas. This is normal and will go away in a few hours.

What are the Risks?

There are some drawbacks to colonoscopy. Your doctor will discuss these with you, and answer your questions.

  • The test is not perfect. Occasionally, important lesions may not be seen, and treatment attempts may be unsuccessful.
  • The medicines may make you sick. You may have nausea, vomiting, hives, dry mouth, or a reddened face and neck.
  • A tender lump may form where the IV was placed. Call your doctor if redness, pain or swelling appears to be spreading.
  • Severe complications of colonoscopy and treatments are rare. These can include bleeding, which is usually minor and self-limiting. In rare cases, blood transfusions or even surgery may be required. Rarely, bleeding may occur up to a week or two after colonoscopic treatment.
  • Tearing (perforation) of the colon is a rare complication which usually requires surgical treatment, possibly including a temporary colostomy.
  • Fatal complications are extremely rare.

Call your Doctor if You…

  • have severe pain.
  • vomit.
  • pass or vomit blood.
  • have chills and fever above 101 degrees.

Why should I visit the Medical University of South Carolina?


photo of Ashley River Tower
MUSC Ashley River Tower

Your doctor will probably agree with you about your preference to come to MUSC. We offer excellent patient care at a state-of-the-art facility, in a historic setting in the southeastern United States. Our doctors are nationally ranked among the highest in the nation. We employ a multidisciplinary approach to the treatment of patients using the latest technology in medicine.

Come see why MUSC is changing what's possible®.

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