Colonoscopy
Colorectal cancer screening · Polyp removal · Evaluation of bowel symptoms — a same-day procedure with proven life-saving benefit.
Colonoscopy is one of the most effective cancer-prevention tools in modern medicine. We don't just find cancer — we prevent it by removing precancerous polyps before they ever become a threat.
Colorectal cancer is one of the most common cancers in the United States — and one of the most preventable. Almost all colorectal cancers begin as polyps: small growths on the inner wall of the colon. Over time, certain polyps can transform into cancer. Colonoscopy identifies these polyps and allows them to be removed before that transformation occurs.
Current guidelines recommend that average-risk adults begin colorectal cancer screening at age 45. People with a family history of colorectal cancer, certain genetic syndromes, or inflammatory bowel disease may need to start earlier and screen more frequently.
Colonoscopy is recommended sooner if you experience: a change in bowel habits lasting more than a few weeks, blood in the stool, unexplained iron-deficiency anemia, unexplained weight loss, persistent abdominal pain, or a family history of colon cancer or polyps.
A colonoscopy is performed under IV sedation, so you are asleep or in a comfortable twilight state for the entire exam. After the bowel preparation has cleansed the colon the day before, a thin flexible scope with a high-definition camera is gently advanced through the rectum and around the entire colon.
Dr. Rios carefully examines the inner lining of the colon. If polyps are found, they are typically removed during the same procedure using specialized tools passed through the scope. Biopsies of suspicious areas are also taken. The entire exam typically takes 20 to 45 minutes.
A thorough bowel prep is essential for an accurate colonoscopy. Even small amounts of residual stool can obscure polyps and lower the quality of the exam. You will be given specific prep instructions tailored to your case. The general framework:
- ◆24 hours before: Switch to a clear-liquid diet (broth, clear juices, gelatin, popsicles — nothing red or purple).
- ◆Evening before: Begin the prescribed oral bowel prep. Drink slowly over the recommended time window.
- ◆Morning of (split-dose): Complete the second half of the prep 4–6 hours before your procedure time. This produces the highest-quality exam.
- ◆Day of: Nothing by mouth at least 2 hours before procedure time. Arrange a driver — you cannot drive after sedation.
Current guidelines recommend starting colorectal cancer screening at age 45 for average-risk individuals. People with a family history of colorectal cancer or polyps, inflammatory bowel disease, or certain genetic syndromes may need to start earlier.
If your colonoscopy is normal and you are at average risk, the standard interval is every 10 years. If polyps are found, the interval is typically shortened to 3–5 years depending on the type and number of polyps.
Yes — a thorough bowel preparation is essential. Even small amounts of stool can obscure polyps and make the exam less accurate. Following the prep instructions carefully is the single most important thing you can do for an effective colonoscopy.
No. You will be given IV sedation and will be asleep or in a twilight state for the entire procedure. Most patients have no recollection of it.
Most polyps are removed during the same procedure using specialized instruments passed through the colonoscope. Removed polyps are sent to pathology to determine the type. Removing polyps before they become cancerous is one of the most effective ways to prevent colorectal cancer.
Colonoscopy is a very safe procedure. Rare risks include bleeding (especially after polyp removal), perforation (less than 1 in 1,000), and adverse reactions to sedation. Dr. Rios will review all risks before your procedure.
You can usually start with light food and beverages an hour or two after the procedure once you are alert. Resume a normal diet that evening unless otherwise instructed. Mild gas and bloating are normal for a few hours.