Polyethylene glycol versus split high-dose senna for bowel preparation: A comparative prospective randomized study

Background and aim: The aim of this study was to compare the quality and tolerability of bowel preparation using split high-doses of sennosides versus split-dose polyethylene glycol (PEG).

Methods: In this prospective, randomized, and endoscopist-blinded study, 474 outpatients were included and randomly assigned to two groups: Group 1 was comprised of 237 patients receiving split high-dose (1000 mg) sennoside solutions, and group 2 included 237 patients receiving 4 L of PEG. The efficacy of the preparations was evaluated on the Boston Bowel Preparation Scale (BBPS), and compliance and adverse effects were recorded.

Results: The quality of colon cleansing and the ease of bowel preparation were significantly better in the senna group; the mean of total BBPS scores was 7.35 in the senna group and 6.57 in the PEG group, cleansing was adequate (BBPS score ≥ 6) in 89.9% of patients taking senna, and 73.8% in the PEG group (P = 0.001). The rates of vomiting in the senna and PEG groups were 12.7% and 29.5%, nausea rates were 28.7% and 43.9%, and abdominal pain rates were 70.9% and 43%, respectively (P < 0.001). Cecal intubation rates in the senna and PEG groups were 95.4% and 86.1% (P = 0.001), and the cecal intubation times were 6.73 ± 2.84 and 5.34 ± 5.98 min, respectively (P = 0.001).

Conclusions: Split high-dose senna is more effective than split-dose PEG in terms of bowel preparation quality and patient compliance. The patients who received senna had significantly less vomiting and nausea but significantly more abdominal pain. Thus, senna may be used as an alternative to PEG for bowel preparation.

Keywords: bowel preparation; colonoscopy; polyethylene glycol; sennosides.