Bisacodyl plus split 2-L polyethylene glycol-citrate-simethicone improves quality of bowel preparation before screening colonoscopy

AIM: To compare the bowel cleansing efficacy, tolerability and acceptability of split 2-L polyethylene glycol (PEG)-citrate-simethicone (PEG-CS) plus bisacodyl (BIS) vs 4-L PEG for fecal occult blood test-positive screening colonoscopy.METHODS: This was a randomised, observer-blind comparative study. Two hundred and sixty-four subjects underwent screening colonoscopy (mean age 62.5 ± 7.4 years, male 61.7%). The primary objective of the study was to compare the bowel cleansing efficacy of the two preparations. Interventions: BIS plus PEG-CS: 3 tablets of 5-mg BIS at 16:00, PEG-CS 1-L at 19:00 and 1-L at 7:00, 4-L PEG: 3-L at 17:00, and 1-L at 7:00. Colonoscopy was carried out after 11:00, at least 3 h after the completion of bowel preparation. Bowel cleansing was evaluated using the Harefield Cleansing Scale.RESULTS: Bowel preparation was successful for 92.8% of subjects in the PEG-CS group and for 92.1% of subjects in the 4-L PEG (RR = 1.01; 95%CI: 0.94-1.08). BIS + PEG-CS was better tolerated than 4-L PEG. A greater rate of patients in the BIS + PEG-CS group had no difficulty and/or were willing to repeat the same preparation compared to split-dose 4-L PEG group. Subjects in the BIS + PEG-CS group rated the prep as good or satisfactory in 90.6% as compared to 77% in the 4-L PEG (P = 0.003). Subjects receiving BIS + PEG-CS stated they fully adhered to instructions drinking all the 2-L solution in 97.1% compared with 87.3% in the 4-L PEG (P = 0.003).CONCLUSION: BIS plus split 2-L PEG-CS was as effective as but better tolerated and accepted than split 4-L PEG for screening colonoscopy. This new procedure may increase the positive attitude and participation to colorectal cancer screening colonoscopy.