Bowel Cleansing Preparation: Is 2 Liters Enough?

Based on a recent meta-analysis, 4 liters of polyethylene glycol (PEG) 3350 with electrolytes given in split doses is still the gold standard of bowel preparations for efficacy. Although low-volume preparations have been shown to be noninferior to 4-L PEG with electrolytes in randomized, controlled trials, they have also been shown to have numerically higher failure rates in several trials (Am J Gastroenterol 2003; 98:2187).

To investigate this issue further, researchers assessed outcomes in 325 patients randomized to receive 2 liters of PEG electrolyte lavage solution (PEG-ELS) plus 15 mg of bisacodyl or 4 liters of PEG-ELS.

The low-volume preparation was noninferior as measured with both the Boston and Ottawa bowel preparation scales. Howev…