Digestive Diseases - Gastroenterology


A colonoscopy lets your doctor examine the lining of your large intestine (colon). During the test, a long, flexible instrument that has a light and a camera at the tip (colonoscope) will be passed through the rectum and around the colon. Your doctor will view the colonoscopy on a monitor to look for any abnormalities that may be present.

Colonoscopy usually is performed to evaluate and treat colon cancer, polyps, gastrointestinal bleeding, and diarrhea. It is the most effective screening test for detecting and treating colon cancer. If necessary, biopsies (tiny tissue samples) may be taken painlessly during the examination and sent for laboratory analysis. Polyps (abnormal growths of tissue) may be removed, and bleeding areas may be identified and treated.

Advanced Colonoscopy and Polypectomy 

Advanced colonoscopy and polypectomy is the highest level of care available for a difficult colonoscopy or removal of complex colon lesions. If you have a polyp in a location difficult to reach under normal circumstances, Mount Sinai’s highly trained physicians can help. At Mount Sinai’s Center for Advanced Colonoscopy and Polypectomy, led by world renowned gastroenterologists Jerome Waye, MD, we have the experience and expertise to safely and effective remove these growths.

Colonoscopy Preparation

In order for your doctor to perform a complete and safe colonoscopy, your colon must be prepared properly. To clean your colon, you will need to follow a set of instructions that includes drinking a special laxative solution the night before your procedure.

Ask your doctor if you have any questions or concerns about the steps you need to take to prepare for your colonoscopy.

  • Laxative Solution: Follow the instructions on the packaging of the solution that your doctor prescribes.
  • Food and Drink: You should be on a modified diet the entire day before your colonoscopy. You may continue to have clear fluids the day of your procedure, up to three hours before your examination. A clear fluid diet includes gelatin, coffee and tea without milk, soft drinks, ices, clear soups, sports drinks such as Gatorade, apple or white grape juice. Do not have any red or purple drinks, gelatin, or popsicles for the 24 hours before your procedure, since the color may interfere with the exam. During this prep period, do not drink any type of alcohol.
  • Medications: Continue to take your medications as usual, even on the day of your examination, unless instructed otherwise by your doctor. Take medicines with a small sip of water on the day of your colonoscopy. If you are a diabetic, please consult with your physician before your examination about your medication schedule. If you use aspirin, you may be able to continue to taking it, unless instructed otherwise. Ask your doctor any questions or concerns you have related to the medications you take.

Specifically, contact your doctor or health care provider for instructions if you take medications to thin your blood or antiplatelet medications such as:

  • Coumadin (warfarin),
  • Lovenox (heparin),
  • Plavix (clopidogrel),
  • Pradaxa (dabigatran),
  • Eliquis (apixaban),
  • Effient (prasugrel),
  • Xarelto (rivaroxaban) or S
  • avaysa (edoxaban), please contact your doctor or health care provider for further instructions.

Please bring a list of your current medications with you on the day of the procedure.

  • Clothing: Dress comfortably in clothing that can be folded. Please do not bring jewelry or other valuables with you.
  • Companion: According to New York State regulations, you must have a companion who is an adult 18 years or older, to accompany you home after the procedure. The sedation you receive may impair your reflexes and judgment. Please note that your procedure will be canceled if a companion is not available to escort you after your procedure.

Please tell the doctor who is performing your colonoscopy if you:

  • Have allergies or reactions to medications
  • Usually take antibiotics for dental procedures
  • Are taking aspirin, arthritis medicines, or blood thinners
  • Have a blood disorder where you bleed easily
  • Think you may be pregnant

Following these instructions is key to the day of your colonoscopy going smoothly, and so you can relax and let your doctor perform the procedure.

About the Procedure

Before Your Colonoscopy: At the beginning of your appointment, you will be meet with a doctor or nurse who will explain the procedure and answer your questions. At that time, you’ll be asked to sign a consent form, giving your permission to have the procedure performed. You will also meet with an anesthesiologist who will be responsible for sedating you and monitoring your breathing and heart rate during your procedure.

You will change into a hospital gown. You will need to remove your eyeglasses and contact lenses.

During Your Colonoscopy: A nurses will take into a procedure room. You will be lying down on your left side in a comfortable position. The anesthesiologist will administer an intravenous (IV) medication that will make you sleepy and relaxed. The doctor will then begin the exam. It generally takes 15 to 60 minutes. Depending on what your doctor sees, he or she may also obtain a biopsy or remove polyps found at this time. These additional steps do not usually cause discomfort.

Any tissue and polyps that the doctor removes are sent to the laboratory for analysis.

During the procedure, you may experience some abdominal cramping and pressure from the air that is introduced into your colon. This is normal and will pass quickly. Your doctor may ask you to change your position during the examination. A nurse will help you move slowly and carefully.

After Your Colonoscopy: When the colonoscopy is completed, you will remain in the recovery area for about 30 minutes. This allows the effects of the sedating medication to wear off. Your physician will discuss the exam results with you and follow-up plans. You will be given a discharge instruction sheet. You will change back into your clothes.

A companion must be available to accompany you home from the procedure, since the sedation will impair your reflexes and judgment.

For the remainder of the day you should not drive a car, operate machinery, or make important decisions. Follow the discharge instruction sheet given to you.

Possible complications: Colonoscopy is a rather common examination. Doctors usually perform colonoscopies on an outpatient basis.

The most common complaint after colonoscopy is that you may feel bloated or have gas cramps. Before you leave, a nurse may suggest that you try to pass gas after your procedure to relieve that feeling.

Serious complications are rare, less than one in 1,000 examinations lead to any complications. However, complications such as reactions to medication, tearing of the intestine, and bleeding sometimes occur. In those rare instances, urgent treatment or surgery may be required. The risks are slightly higher when colonoscopy is treatment to remove polyps.

Inform us immediately if you have any severe pain, black tarry stools, or persistent bleeding, fever, or chills in the hours or days after your colonoscopy.

Your doctor and healthcare team are committed to your wellbeing and want you to have a safe and comfortable experience. Please ask us if you have any questions.