Poor Colonoscopy Prep Can Hide Polyps

Hi Folks,

Dr. Tabibian here.

It's the night before your colonoscopy. You're staring at a jug of prep solution, a clock, and a long list of rules.

It can be very stressful. But it doesn’t have to be as bad as you might think..

Why You Should Read This

Does the prep really matter that much? (Yes! It determines how much of your colon can be seen.)

• A poor prep can hide polyps. Leftover stool coats the colon lining, which can lead to missed polyps and sometimes a repeat procedure
• Splitting the dose is the standard. The major U.S. gastroenterology societies recommend it for every prep regimen

Why the Split Dose Works

A prep taken entirely the day before has hours to get undone before your procedure. It’s also more difficult to finish drinking all at once and more likely to cause nausea and abdominal discomfort.

Taking the second half closer to your procedure keeps the colon clearer when the scope goes in. Even if you feel like there is nothing left, your liver still produces bile that can stain your colon and make it hard to see.

• Dose one: the afternoon before
• Dose two: several hours after the first dose (but at least six hours before your procedure time)

For a late afternoon procedure, a same-day schedule is sometimes even used. It’s important to follow the plan your doctor’s office gave you.

Common Prep Pitfalls

• Not modifying your diet prior to prep day. In a sense, the prep process starts prior to the day before your procedure. It’s important to avoid fibrous foods 3-5 days prior to your procedure.
• Iron supplements. They turn stool dark and sticky, which can cloud the view. Many instructions say to stop oral iron several days ahead, often around 5 to 7. It’s good to by the timing on your instructions
• A ride home. If you're sedated, plan on someone driving you.

The prep is one part of a colonoscopy you can control, so it's worth getting right.

Until next time,
Dr. Tabibian