Effect of Adding Simethicone to Split-dose Polyethylene Glycol for Bowel Preparation in a Screening Colonoscopy Setting

Colonoscopy is currently accepted as the gold standard in screening, surveillance and prevention for colorectal cancer (CRC), and therefore, its quality is a major priority.
The quality of colonoscopy is greatly dependent on the quality of the bowel preparation. Standard bowel cleansing includes a low-fibre diet on the day preceding the exam and a split regimen of 4 litres of polyethylene glycol (PEG) solution.
In order to improve bowel cleansing some additional measures are available. Simethicone is an inexpensive and safe antifoaming agent that reduces the surface tension of air bubbles, theoretically presenting several benefits such as increased tolerability to the preparation, thereby improving the quality of the preparation and, secondly, adenoma detection (ADR) and cecal intubation rates (CIR). However, its role remains controversial, with some publications supporting its administration and others failing to demonstrate clear benefits.
The main aim of this study is to assess if addition of simethicone to a split-dose cleansing regimen of 4 litres of PEG improves adequate bowel preparation rate.