A Prospective Randomized Trial Comparing Low-Dose Oral Sodium Phosphate Plus Stimulant Laxatives with Large Volume Polyethylene Glycol Solution for Colon Cleansing

This study examined whether the combination of a single dose (45 ml) oral sodium phosphate (NaP), four bisacodyl tablets (5 mg), and one bisacodyl enema (10 mg) preparation, Fleet Prep Kit 3 (FPK #3), was better tolerated and more efficacious than 4 L polyethylene glycol solution (PEG) for colonic cleansing prior to colonoscopy. One hundred and seventy-one patients were enrolled in this prospective, randomized, single-blinded study designed to detect a 20% or greater difference in patient tolerance and effectiveness in colonic cleansing between the two agents. The single dose of NaP and the bisacodyl tablets were administered at 1900 h and at 2100 h, respectively, the evening prior to colonoscopy and the bisacodyl enema 2 h before the procedure. PEG was consumed over 1-2 h the evening prior to colonoscopy. Most patients (84%) found the FPK #3 easy or tolerable compared to only 33% receiving PEG (p < 0.001). Over 40% could not complete the PEG. There was no detectable difference in the efficacy between the two preparations (p= 0.74). Comparison of biochemical and hemodynamic values obtained before and after colonic cleansing did not reveal any significant differences apart from hyperphosphatemia in a few patients (16%) receiving FPK #3 and minor changes in blood urea nitrogen and chloride. These findings suggest that FPK #3 is better tolerated and as safe as PEG but does not provide more efficacious cleansing of the colon.