The primary function of the colon (also called the large intestine) is to absorb fluids from the liquid waste material that comes from the small intestine. When malfunctions occur, the colon can sometimes be the source of abdominal pain, diarrhea or constipation.

What is a colonoscopy?



Colonoscopy is a procedure to examine the lining of the entire colon (large bowel) using a flexible instrument, the colonoscope. Your physician may recommend Colonoscopy because of unexplained rectal bleeding, unexplained pain, to evaluate a condition such as inflammatory bowel disease, or because of a history of colon polyps in you or in a close relative, or in the evaluation to rule out colon cancer. This is an outpatient procedure which generally lasts 30 to 60 minutes. Tumors or early cancers can be detected and removed during Colonoscopy, thereby avoiding surgery and saving lives.

"Colon" refers to the large intestine or the last four-to-six feet of the digestive tract. "Oscopy" means "looking into." Colonoscopy allows your physician to observe the entire length of the colon effectively and generally with little or no discomfort to the patient.

The instrument used in colonoscopy is called a colonoscope. It is a long, thin, flexible tube about twice the diameter of a pencil. There are approximately four channels within the "scope" through which the physician may illuminate, wash, suction, photograph and biopsy the colon. These channels provide the means for removal of most polyps and the cauterization of blood vessels to prevent bleeding.

Where and how is it done?

Arrangements for your procedure will be made by this office. Also, special written instructions for preparing your bowel (i.e., cleaning it out) involving a special diet and medication instructions will be given to you. These are very important to allow a good quality examination and should be followed carefully!
Upon admission you will be asked a series of medically related questions. You will change into a procedure gown and be shown to a bed. Due to the amnesia-like effects of the sedation used for colonoscopy, it is likely you will not remember information given to you immediately following the procedure. Therefore, your doctors will have the office nurse/clinician speak with you and your family after the completion of the colonoscopy. At that time the procedure findings will be explained to you; you will be scheduled for any followup procedures that might be necessary, and any questions you and your family might have will be answered.

In our experience, the majority of patients want to go home as soon as possible after their procedure. However, if you wish to speak to your physician, he/she will be happy to accommodate your request.
Due to the nature of the medications used during the procedure, it is absolutely mandatory that you have someone meet you in the designated waiting area after the procedure to drive you home. Once you have returned home, do not operate any dangerous machinery and be sure not to drive for at least 24 hours, since minor effects of the drugs may persist the rest of that day.

Once you have completed the admission procedure, you will have an intravenous line started in your arm or hand. This provides the means by which your physician can administer sedation and pain medication before and during the procedure. If you have any history of drug reactions or allergies, heart or lung condition, artificial joints (e.g., artificial hip or knee), you should be sure to inform your nurse and doctor before the procedure begins. Please notify us if you are taking the medication NARDIL.

Colonoscopy is performed in a specially equipped room where you will be asked to turn on your left side with your knees drawn up. Every effort will be made to ensure that you are as comfortable and relaxed as possible. Your pulse, blood pressure and oxygen level will be monitored continuously throughout the procedure. After lubricating both the colonoscope and the rectal area, your doctor will gently insert the colonoscope. If there is any resistance, you may be asked to aid the insertion of the instrument by gently bearing down, as if you were having a bowel movement. Since the bowel should be totally empty, the chance of soiling oneself with fecal matter is almost non-existent.
During the procedure, it is necessary to inflate the bowel with air in order to smooth out the normally wrinkled walls of the colon. This will ease the insertion of the scope and improve the viewing of the lining of the colon, but at the same time, this may cause you to feel as if you have to have a bowel movement. This feeling of urgency will soon pass.

Your doctor will examine the entire large bowel up to and including the ileocecal valve which marks the junction of the small and large intestine. The colonoscope will be removed slowly as the doctor double-checks each section of the intestine upon withdrawal. If, during the inspection of the colon, any inflammation, irregularity or growth is discovered, your physician may painlessly remove or biopsy that tissue. Biopsy forceps can be inserted through the hollow channel of the scope, allowing your doctor to remove a tissue sample for testing. Removal or biopsy will only be performed when necessary and permission to do it is included in the consent you sign.

Once the inspection is complete, the colonoscope will be carefully removed. The entire examination requires between thirty minutes and one hour. You will then be wheeled out to the postoperative area for recovery. It is very common, due to the nature of the medications used for sedation, for patients to remember little or nothing of the procedure. You may experience some abdominal discomfort due to the presence of gas which may last up to several hours, but generally this is minimal.

What are the risks?

It is your right to be thoroughly informed of the risks and possible complications before you decide whether or not to undergo the recommended colonoscopy procedure.

  • There is a 1 in 100 chance of some complication occurring when colonoscopy is used to diagnose your problem, but serious problems are very uncommon.
  • There is a 1 in 300 chance of a significant amount of bleeding from the colon or rectum. Minor bleeding is more common but seldom requires treatment. Any persistent bleeding should be reported to your physician.
  • There is a 1 in 500 chance of a puncture of the colon.
  • There is a risk of temporary irregularity of the heart rhythm. For this reason, if you have a history of heart disease, your heart may be monitored with an electrocardiogram to minimize risk to you.
  • There is a risk of an allergic reaction to the drugs administered during the procedure, although these are rare.
  • Death is extremely rare but remains a possibility.

Although any medical test has some risk associated with it, in actuality, serious problems with colonoscopy are very uncommon and when they occur, are very treatable. Because of its acceptability, low risk, accuracy and the wide variety of tasks it can accomplish, colonoscopy is well recognized as a very important test in appropriate situations and is used frequently in patients with lower bowel symptoms or problems.

What are the side effects?

Abdominal gas or bloating caused by the introduction of air into the colon to enhance and ensure good visualization. Walking assists the passing of gas. Refrain from eating large amounts of food until you have returned to your normal state of comfort.

Uncommonly, nausea may also be a result of the abdominal gas and/or the use of medications during the procedure. It is recommended that you remain on clear fluids until nausea subsides. Should vomiting occur over an extended period of time (more than 6 hours), please notify your physician. Bed rest is recommended.

Localized irritation of the vein (phlebitis) is rare but may occur at the site of medication injection. A tender lump develops which may remain for several weeks to several months, but goes away eventually. Elevation of the arm and hot, wet compresses applied to the site several times per day should rectify the situation. If a red streak should form which appears to follow the route of a vein or extends up your arm, please notify your doctor at once.
If any serious or persistent symptoms develop, you should notify your doctor.

What are the alternatives?

The most common alternative to colonoscopy is barium enema. This examination requires barium (a chalky liquid) to be inserted into the rectum which fills the colon, after which x-rays are taken. Some abnormalities of the colon can be detected by studying these films. However, this procedure is generally recognized as not being as accurate as colonoscopy, nor does it allow for biopsy or removal of polyps.
Three procedures which may be done prior to colonoscopy (but are not considered alternatives to colonoscopy) are sigmoidoscopy, CAT scan and nuclear scan. Since findings from these three procedures may need to be confirmed by colonoscopy anyway, your physician may not perform them.

Pre Procedure

When your procedure is scheduled, you will be given specific instruction for preparing for your exam.  The prep instructions vary, depending on the time of your appointment as well as other factors.  If you have any questions regarding your prep, contact our office at 541 868-9500.  Urgent concerns outside of the office hours should be directed to the on-call physician at 541 868-9500 (toll free 877 484-4501).

Post Procedure

Directly following your colonoscopy and possibly for several hours thereafter, you may experience abdominal gas or the sensation of being bloated. This is due to the introduction of air into the colon during the procedure in order to facilitate the movement of the colonoscope within the large intestine, and to increase visualization by smoothing out the normally wrinkled bowel wall. You will experience increased flatulence (bowel gas), until your colon returns to its normal state (24 hours). Walking assists your bowel to rid itself of gas. One may experience loose stool or no stool for up to 3 days following the procedure. If you have no bowel movement by the third day, you may take a fiber supplement or milk of magnesia.You may eat when you get home; however, be sure to consume only small portions of food until you rid yourself of the majority of the gas in your colon, as its presence may cause you to feel nauseated. (Eating a full meal stretches the stomach and increases the bloated discomfort.)

Nausea may be caused by the presence of gas, effects of the medication used or pain. This condition may last several hours but your doctor should be notified if it persists into the following day. Drink only clear liquids (any fluid you can see through), and do not eat solid food until the nausea subsides. Bed rest is recommended. If vomiting should occur notify your physician.

Due to the action of Colyte in the bowel and the frequent elimination which follows, your hemorrhoids may be irritated to the point of bleeding. You may experience continued irritation for the next few days, until your rectal tissue has a chance to recover from the trauma. You may use an over-the-counter preparation such as Preparation-H or Anusol to help ease the soreness. At no time should the present bleeding exceed the pre-procedure amount.

After the removal of polyps, you may notice a small streak of fresh blood on the toilet tissue or in the toilet bowl. This is not a matter for concern as it may indicate only slight trauma to the wall of the bowel during the manipulation and passage of the colonoscope and is readily repaired by your body.


Localized irritation of the vein (phlebitis) may occur at the site of medication injection and is not unusual. There may be a red streak going up your arm that is best treated with moist hot packs. If it progresses, call Eugene Gastroenterology as antibiotic therapy may be required to resolve this condition.


Forgetfulness is normal immediately after the procedure and is due to the use of an amnesic drug required for adequate sedation during the colonoscopy. Should you have any questions after your procedure, please call our office and your call will be directed to your physician’s triage nurse. (If this is a toll call, call 1-877-484-4501.)

A pathology report of any biopsied tissue should be received by our office in 14 days. If you have not heard from us within this time frame, please call our office and your call will be directed to your physician’s triage nurse.

If you have had polyps removed, please DO NOT take products with aspirin or ibuprofen (Excedrin, Aleve, Motrin, Naprosyn, arthritis medications or Alka-Seltzer) for five days, as this lengthens the time it takes for your blood to coagulate (clot) at the biopsy site(s) and can increase the risk of post-procedure bleeding.



Note: The information in this section is provided as a supplement to information discussed with your healthcare provider. It is not intended to serve as a complete description of a particular topic or substitute for a clinic visit.