What Is a Colonoscopy?

The colonoscopy exam

A colonoscopy is an exam that a doctor—usually a gastroenterologist—performs to visually examine the inside of your colon. Colonoscopies are considered the gold standard for detecting abnormalities within the colon.

In addition to searching for early signs of colon cancer, a colonoscopy can be used to diagnose the reason for a number of gastrointestinal (GI) issues, including

  • Chronic, unexplained abdominal or rectal pain
  • Rectal bleeding
  • An unexplained change in bowel habits (eg, persistent diarrhea)
  • The feeling that your bowel doesn't empty completely
  • Unintentional weight loss
  • Iron deficiency anemia
  • Inflammatory bowel disease, including ulcerative colitis and Crohn's disease
  • Irritable bowel syndrome

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  • This is another precancerous growth on the colon wall
  • If caught early, it can be removed, aiding in the prevention of colon cancer
  • Difficult to detect without effective prepping and an accurate colonoscopy
  • An abnormal tissue growth on the wall of the colon
  • Usually slow growing and the first sign of potential colon cancer
  • The colonoscopy is one of the most accurate methods of detection
  • If caught early, polyps can be removed, aiding in the prevention of colon cancer
  • Symptoms may not be noticeable
  • Abnormal bands of tissue that grow in the body
  • Similar to scar tissue
  • Most commonly caused by abdominal surgical procedures
  • Common complication is intestinal obstruction—an adhesion wraps around the intestine and prevents flow of the digestive tract
  • May relieve itself or require medical intervention
  • A form of inflammatory bowel disease that includes inflammation and sores, called ulcers, in the lining of the rectum and colon
  • Ulcers form where inflammation destroys the cells of the colon wall, eventually bleeding and producing pus
  • Colon inflammation will make the colon empty frequently, causing diarrhea
  • A chronic inflammatory bowel disease that affects the entire wall of the colon
  • Can affect any part of the gastrointestinal tract from the mouth to the anus
  • Symptoms vary greatly
  • Primary symptoms are abdominal pain, diarrhea (may contain blood), constipation, vomiting, weight loss, or weight gain
  • If polyps or lesions are left undetected, they can develop into cancer
  • Generally, polyps grow very slowly
  • Early detection and removal is essential to cancer prevention
  • Colonoscopy is the key to early detection and prevention
  • Involves the formation of pouches (diverticula) on the outside of the colon
  • Results when pouches become inflamed or infected due to blockage, possibly by feces or food particles
  • Symptoms may include abdominal pain, fever, nausea, vomiting, chills, cramping, and constipation
  • A condition characterized by inflammation of the appendix
  • Mild cases may resolve without treatment, but most require removal
  • Removal is typically performed using minimally invasive surgery

Who is a candidate for colonoscopy?

Both men and women should have their first colonoscopy by age 50, unless there are reasons for your healthcare provider to recommend one sooner. These reasons may include a family history of colon cancer or colon polyps, a personal history of inflammatory bowel disease, or any of the GI issues listed above. Race is another factor. African Americans should have their first colonoscopy screening by age 45, as they have a higher risk of and death rate from colon cancer.

Colonoscopy may be contraindicated in some patients, including elderly patients and patients with bleeding disorders, pulmonary disease, or a prior allergic reaction to sedation. However, in a vast majority of patients, the benefits outweigh the risks, and colonoscopy is an important step in preventing colon cancer. It is important for you to talk to your doctor about the risks associated with colonoscopy to be sure the procedure is right for you.

Important Safety Information about MOVIPREP

MOVIPREP® (PEG-3350, sodium sulfate, sodium chloride, potassium chloride, sodium ascorbate and ascorbic acid for oral solution) is an osmotic laxative indicated for cleansing of the colon as a preparation for colonoscopy in adults 18 years of age or older. MOVIPREP is contraindicated in patients with gastrointestinal (GI) obstruction, bowel perforation, gastric retention, ileus, toxic colitis or toxic megacolon, and patients who have had a severe hypersensitivity reaction to any of its components. MOVIPREP should be used with caution in patients at risk of or with fluid and electrolyte abnormalities, hyponatremia, arrhythmias, seizures, in patients with impaired renal function or patients taking concomitant medications that affect renal function, patients with known or suspected inflammatory bowel disease, patients with suspected GI obstruction or perforation, patients at risk for aspiration, and patients with glucose-6-phosphate dehydrogenase deficiency. Most common adverse reactions for split dosing (incidence ≥5%) are malaise, nausea, abdominal pain, vomiting, and upper abdominal pain. The most common adverse reactions for evening only dosing (incidence ≥5%) are abdominal distension, anal discomfort, thirst, nausea, abdominal pain, sleep disorder, rigors, hunger, malaise, vomiting, and dizziness. MOVIPREP contains 233 mg of phenylalanine per treatment. Advise patients to hydrate adequately before, during, and after the use of MOVIPREP.

You are encouraged to report negative side effects to the FDA. Visit www.fda.gov/safety/medwatch/ or call 1-800-FDA-1088.

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