Bowel preparation prior to colonoscopy: a continual search for excellence.

Bowel preparation prior to colonoscopy is essential to maximize the benefits of colonoscopy. Numerous bowel preparations have been studied, ranging from 4 L polyethylene glycol (PEG) to split-dose regimens to 2 L PEG with an adjunct laxative (senna, bisacodyl, ascorbic acid). Due to the large volume of PEG required for adequate bowel preparation, many studies have focused on reducing this large volume to only 2 L PEG with the addition of an adjunct. Recently, a randomized controlled trial by Tajika et al showed that the addition of mosapride to only 1.5 L PEG was non-inferior to mosapride and 2 L PEG for bowel cleansing but did provide improvements in patient tolerance. This study offers yet another potential bowel preparation for patients undergoing colonoscopy and may trigger further studies with 1.5 L PEG with an adjunct. In this letter, we discuss the current state of bowel preparation prior to colonoscopy and offer information to guide clinicians on choosing the appropriate bowel preparation for their patients.