What happens during a colonoscopy, and when do I need one?

By Brian Clark, M.D.
Hallmark Health Medical Associates

Dr. Brian Clark

Would you want to lower your chance of dying from a disease by 50 percent or more?

That’s a no-brainer, right?

Colon cancer is preventable. The best way to ensure you never get colon cancer is to get a colonoscopy.  While some people may need to start earlier, everyone should have this simple procedure starting at age 50. If nothing is found, you may not need another one for 10 years. If something is found, you’ll be glad you did it.

As a gastroenterologist, I talk about poop and colons every day. The general public, however, isn’t usually open about these kinds of topics. To me, the impact of saving lives far outweighs that gross factor or having uncomfortable conversations.  

What happens during a colonoscopy?

I know one thing for sure – there are plenty of people out there who are flat-out misinformed about what happens during a colonoscopy.

There is very little, if any, pain during a colonoscopy. Discomfort, rarely, but not much pain. At many facilities, an anesthesia doctor puts you under before the procedure, so the vast majority of patients feel nothing at all. In fact, when they’re done, my patients often say, “Oh, it’s already over? That wasn’t bad at all!”

Here’s what happens during a colonoscopy, from the beginning:

The day before, you will need to be on a clear-liquid diet and drink a solution to clean out your colon (large intestine).  The amount of this solution can range from as little as two liters to four liters. For instance, our most commonly used preparation involves mixing a laxative with Gatorade. You drink two 32-ounce bottles of this the night before, and one bottle the morning of your appointment.

You will have diarrhea the night before your colonoscopy due to the prep solution. Many patients say this is the worst part. Unfortunately, it’s necessary to ensure an accurate exam. We will be looking for pre-cancerous tissue and removing any polyps we find. If your colon isn’t clear when we do a colonoscopy, it can be much easier to miss this early form of preventable cancer.

Most of my patients are asleep during the actual colonoscopy, and most don’t remember anything when they wake up afterward.

During the procedure, we gently insert a flexible camera scope in your rectum to examine the entire colon. We look for cancer, those pre-cancerous polyps, and any other abnormalities. We can remove the polyps right then and there, eliminating the threat. When a polyp is completely removed from your intestine that polyp can no longer turn into cancer – ever. After the procedure, the polyps will be analyzed by a pathologist to determine if they are cancerous or pre-cancerous.

The colonoscopy may take less than 30 minutes to complete, but it can take slightly longer if we find polyps to remove. Because of the anesthesia, you’ll need to be in a recovery room for a short time before you’ll be able to leave. You’ll also need to have someone drive you home.

Why do I need a colonoscopy?

There are a lot of reasons why people avoid getting much-needed colonoscopies:

• Some don’t know they need one.
• Some think it will be too painful.
• Others are scared of what the doctor might find.

The fact is, colon cancer is extremely common. It is the third-most common cancer in the U.S., with about 130,000 new cases each year. Around 50,000 Americans die from colon cancer each year.

Anyone, male or female, can get colon cancer. It’s gender blind. Women have a slightly lower risk of developing colon cancer than men, but both men and women should take it seriously.

The benefits of colonoscopy far, far outweigh the negatives for preventing colon cancer. This simple procedure is the most effective way to prevent colon cancer. Research shows that when you get a colonoscopy, your risk of dying from colon cancer is reduced by 50 percent or more.

Still not convinced? Think about it this way – We have screening methods for breast cancer, lung cancer, and prostate cancer. But none of them are nearly as effective at preventing death from cancer as colonoscopies. A colonoscopy is one of the few screening methods that effectively identifies and eliminates pre-cancer.

I know what you’re saying – “But I feel just fine!” Usually you don’t have symptoms from cancer until it’s in advanced stages, and certainly colon cancer is one of those types.

When we catch it early, the prognosis for colon cancer is very good. In early-stage colon cancer, the five-year survival rate is above 90 percent. Symptoms usually start appearing when colon cancer is in the later stages. When the cancer is metastatic, meaning it has spread to other organs, the 5-year survival rate is around 12 percent.

Here’s the best way to think about it: The point of screening is to prevent cancer or to find it early enough that it’s treatable and curable. We call it preventative medicine.

When should I get a colonoscopy?

Everyone who is over 50 years old – man or woman – should get a colonoscopy at least every 10 years. Some people should be screened earlier:

• African Americans should have regular colonoscopies starting at age 45.
• People who have a family history of colon cancer or colon polyps are at higher risk for colon cancer. These people should talk to their primary care doctor or their gastroenterologist about the best time to start screening.
• People with other diseases of the colon such as ulcerative colitis or Crohn’s disease may be at higher risk of colon cancer. These people should talk to their primary care doctor or their gastroenterologist about the best time to start screening.
• If you have rectal bleeding or a change in bowel habits you may need a colonoscopy sooner.

We don’t know why African Americans are risk for colon cancer at younger ages, but genetics likely plays a large role. African Americans tend to have more cancer in the beginning part of the colon, and cancers in that area can be more difficult to detect. That’s why some guidelines recommend that African Americans get screened younger, at age 45.

If you have a colonoscopy and we don’t find any polyps or cancer, you won’t need another colonoscopy for 10 years unless you have a family history or develop a symptom like bleeding. We know that in the vast majority of cases it takes longer than that for polyps to turn into cancer. If you’re in a higher-risk category, your gastroenterologist may recommend screening more frequently.

Bottom line: Colon cancer is preventable. What are you waiting for? Get screened NOW!

Are you or is one of your family members age 50 or older? Request an appointment with Dr. Clark for a colonoscopy today.