When your doctor says it’s time to schedule a colonoscopy, do you start thinking up excuses to put it off? You may worry about unpleasantness and inconvenience as you prepare for the exam. But you should know that the prep process is much easier these days.
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Yes, one of the keys to a successful colonoscopy is getting your colon as clean as possible, which includes your diet days before the exam and the laxative “clean-out” beforehand. But improvements — in the amount of liquid you drink and the timing — make the whole process easier to swallow.
Here gastroenterologist Carol Burke, MD, explains what you need to know.
Regular colonoscopies can save your life
Most patients who develop colon cancer have no obvious risk factors. “If you have a colon, you are at risk for colon cancer. Colon cancer arises from colon polyps. If colon polyps are removed, colon cancer is decreased. Even if colon cancer is present, when detectable in early stages, it is curable. That’s why colonoscopies are vital for your health,” Dr. Burke says.
The American Cancer Society estimates that about 53,000 people will die from colorectal cancer in 2021. Colorectal cancer is one of the leading causes of cancer-related deaths in U.S. for men and women.
The good news? The death rate continues to drop, thanks to early screenings and better treatment. The key is to have regular exams beginning at age 45, or earlier if you have risk factors.
Excellent quality of colon cleansing (the needed dietary changes and using the bowel preparation laxative) helps your doctor spot signs of trouble.
Drinking a laxative prep to cleanse your bowel isn’t everyone’s favorite thing to do. But it’s a key part of your colonoscopy. “If the colon lining is not clear of solid and liquid, then bowel residue can cover polyps — which are a precursor for cancer — and can be missed,” Dr. Burke says.
Good preps make the exam more effective and efficient. If your prep is poor, the doctor may need to repeat your exam — and you’ll need to repeat the prep.
3 steps for a good colonoscopy prep
You’ll start preparing for your colonoscopy a couple of days before you drink the bowel-cleansing agent.
- Cut out fiber. Two days before your exam, you’ll switch to a low-fiber diet. Fiber residue can clog the scope and is not easy to remove by colonoscopy.
- Switch to clear liquids. One day before the exam, you’ll drink only clear liquids. “You need a lot of clear liquids to stay optimally hydrated and help flush the prep through your intestinal tract,” Dr. Burke says.
- Start the prep. The national (and international) standard for high-quality bowel cleansing is a split-dose regimen, where you take half the prep the night before and the other half four hours before the procedure. If you have an afternoon exam, you can drink the whole prep the morning of the procedure. “We have learned that having fewer hours between finishing the prep and starting the colonoscopy is the optimal cleansing strategy,” says Dr. Burke. There is also a new, FDA-approved bowel prep tablet that can work as fast as 30 minutes. Consult with your doctor to find out if this tablet could work for you.
In a recent study, she and other researchers compared the split-dose prep to other conventional single dose, night-before bowel-cleansing methods. They found that a split-dose bowel preparation decreased the intensity and duration of bowel movements, caused less patient inconvenience and improved bowel preparation.
A better-tasting solution
Dr. Burke says liquid bowel-cleansing agents have become more palatable in recent years. Several better-tasting and lower-volume solutions are now being used. Along with the half-gallon and split-dose approaches, this improves your colonoscopy experience.
“The old gallon or 4 liters of laxative solution has stiff competition these days with 3-liter, 2-liter and 10-ounce alternatives,” she says. “Of course, the lower-volume preps require additional clear liquids for action. Some of my patients have actually said the newest low-volume preps taste great, or that they love them.”
Look for an expert to perform your colonoscopy
Talk to your primary care doctor about when to start having regular colonoscopies. Your age, race and family history will affect the timing.
Quality matters when it comes to choosing your endoscopist. “It’s best to have your doctor refer you to an endoscopist, who has special training, meets national quality colonoscopy benchmarks and is highly experienced in colonoscopy,” says Dr. Burke.
When you’re not sure of a healthcare provider’s credentials, ask about their complication rate, completion rate and adenoma (polyp) detection rate before having a colonoscopy, she says. The American Society of Gastrointestinal Endoscopy offers a list of questions that you can ask.