Updated Guidelines Refine Best Practices for Colonoscopy Bowel Prep

Today, the US Multi-Society Task Force on Colorectal Cancer (MSTFCRC) released updated guidelines for optimizing bowel preparation before colonoscopy, refining best practices from its 2014 recommendations.¹ The guidelines emphasize the effectiveness of split-dose regimens, flexibility in dietary restrictions, and the importance of tracking bowel prep adequacy to ensure high-quality screenings for colorectal cancer.

The US Multi-Society Task Force (MSTFCRC) updates 2014 recommendations, emphasizing split-dose prep, diet flexibility, and quality tracking. | Image credit: shevchukandrey - stock.adobe.com

“Our guidance, which is an update of the 2014 recommendations, aims to help all gastroenterologists achieve a benchmark of 90% of exams with adequate bowel preparation,” Joseph C. Anderson, MD, one of the co–lead authors of the MSTFCRC recommendations, said in a statement.² “Highlights include the use of low volume bowel preparation and the adjunctive use of simethicone.”

The MSTFCRC provides evidence-based recommendations to optimize bowel preparation for colonoscopy, covering key areas such as patient education, dietary restrictions, preparation regimens, and strategies for improving cleansing adequacy.

While most recommendations target outpatients at low risk for inadequate cleansing, the guidelines also address strategies for higher-risk individuals. The MSTFCRC is comprised of representatives from the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy.

Choice of Prep, Dosing and Timing, and Dietary Restrictions

The recommendations emphasize a patient-centered approach to bowel preparation, considering factors such as individual medical history, comorbidities, medication use, cost, and ease of obtaining and consuming purgatives. The choice of preparation regimen should be tailored to the patient, with prior colonoscopy outcomes informing decisions when available. The task force highlights the importance of dose timing, recommending a split-dose regimen—with the second dose taken 4 to 6 hours before the procedure and completed at least 2 hours before start time—as the preferred approach for morning colonoscopies. A same-day regimen is an acceptable alternative for afternoon procedures, though considered inferior for morning cases. Dietary restrictions should be limited to the day before the procedure for low-risk patients, with clear liquids or low-fiber, low-residue diets permitted for early and midday meals. While no single purgative is deemed superior, the guidelines include a comparative table detailing commonly used bowel prep agents, their side effects, and contraindications.

Additionally, the MSTFCRC emphasizes the importance of assessing and documenting bowel preparation quality in the endoscopy report, ensuring that findings are clearly communicated using standardized descriptors. The task force recommends that "adequate bowel preparation" be used to indicate that a colonoscopy’s findings can reliably determine appropriate screening or surveillance intervals. To uphold high-quality standards, the guidelines call for routine tracking of bowel preparation adequacy rates, with a benchmark of 90% or greater adequacy at both the individual endoscopist and endoscopy unit levels.

“Bowel preparation is a vital part of colonoscopy,” Brian C. Jacobson, MD, MPH, also a co–lead author, added in the statement. “If the colon is not adequately cleaned, the person performing the colonoscopy may miss important findings such as small polyps. Many cases end up cancelled when the bowel preparation is inadequate, and that creates tremendous frustration for patients and inefficient use of resources.”

Overall, the researchers believe the updated MSTFCRC recommendations reinforce the critical role of proper bowel preparation in ensuring high-quality colonoscopies, optimizing detection rates, and guiding appropriate screening and surveillance intervals. These guidelines aim to provide a comprehensive framework to enhance the effectiveness of colonoscopies and ultimately support better prevention and early detection of colorectal cancer.

References

1. Jacobson BC, Anderson JC, Burke CA, et al. Optimizing bowel preparation quality for colonoscopy: consensus recommendations by the US Multi-Society Task Force on Colorectal Cancer. Am J Gastroenterol. Published online March 4, 2025. doi:10.14309/ajg.0000000000003287

2. Evidence-based strategies improve colonoscopy bowel preparation quality, performance, and patient experience. American College of Gastroenterology. News release. March 4, 2025. Accessed March 4, 2025. https://www.newswise.com/articles/view/824464