What to Expect During a Colonoscopy

Most people agree the prep for a colonoscopy is worse than the test

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A colonoscopy is an effective test used in the process of making a diagnosis of inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and other digestive disorders. A gastroenterologist (a specialist in digestive disease) or a colorectal surgeon should perform the test. A long, flexible tube with a light and a camera on the end is inserted into the anus, and guided through the large intestine.

A colonoscopy sounds challenging but it's a common, routine test that can yield so many benefits. Screening for colorectal cancer can not only detect cancer early, but also eliminate the threat of cancer when polyps are removed during the test. This test does require a preparation day and then another day to recover, but it only needs to be repeated every so often (such as once a year in the case of IBD or perhaps 5 or 10 for colorectal cancer screening).

Preparing for a Colonoscopy

In the days before having a colonoscopy, a patient must clean their colon of all waste materials. Doctors may prescribe different techniques for different patients. For example, a patient with severe diarrhea may not need as much prep as a person with a healthier bowel. Someone who has had surgery on their intestines and has an ostomy or a j-pouch may have a different prep than someone who has never had surgery.

Common methods to prepare the colon include drinking a solution to stimulate the bowel, laxatives, and enemas. By following the doctors' instructions correctly, the large intestine will be clean and free of waste so any potential problems can be more easily seen and diagnosed.

During the Colonoscopy

Patients are normally sedated through an IV during the procedure. Sedation is an important point to discuss with the doctor before the day of the test to understand which medications are used and what to expect. The doctor may also use a heart monitor, oxygen, and other monitoring equipment to ensure the safety and comfort of the patient during the test. The entire colonoscopy procedure commonly takes about 30 minutes. The doctor may take some biopsies, a small sample of tissue that will be sent to a pathologist for testing to ensure an accurate diagnosis.

After the Colonoscopy

After the colonoscopy, patients are monitored for another period of time to reverse the sedation and make sure no complications have occurred. Because the colonoscope introduces air into the colon, there will be some bloating that will be relieved by passing gas. Patients should arrange to have someone drive them home from the procedure, as they will be quite groggy. This person can also remember any further instructions given by the medical staff.

At some point after the procedure, patients will meet again with the doctor to discuss any findings. The results of the biopsies will be available at this time as well as any other pathology that was seen during the test.

Potential Complications

Complications from a colonoscopy are uncommon and are not a reason to postpone or avoid having the test. Colonoscopy, on the whole, is quite safe and is necessary for cancer screening and for monitoring disease. Most people will find that grogginess from the anesthesia wears off the day of the test and by the next day, a normal routine can be resumed. If there is excessive pain, bleeding from the rectum, vomiting, or nausea, contact the doctor's office to determine next steps. If symptoms appear to be a medical emergency, seek medical attention right away. 

A Word From Verywell

A colonoscopy is a vital test because it can not only help diagnose a disease or condition, it can actually be used to help prevent colon cancer. When polyps are removed during a colonoscopy, this removes the chance that those polyps may become cancerous. For people with IBD, a colonoscopy is often done at yearly or other regular intervals to gauge disease activity. There are a variety of preparations available and every physician has their own preferences. Patients who have colonoscopies on a regular basis may also have a particular way of preparing that works well for them. Any change or question about the prep should be discussed with the physician.

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