A NEW study has found that a low dose of simethicone (200 mg) combined with 3 L of polyethylene glycol electrolyte solution (PEG-ELS) is as effective as a higher 1200 mg dose for bowel preparation in afternoon colonoscopy. The findings suggest that using a smaller dose could simplify preparation protocols and reduce medication use without compromising diagnostic quality.
Comparable cleansing and detection rates
In this prospective, randomised, and observer-blinded trial, 668 patients undergoing afternoon colonoscopy were assigned to receive either 200 mg or 1200 mg of simethicone alongside PEG-ELS. The primary outcome was the rate of adequate bowel preparation, defined by a Boston Bowel Preparation Scale (BBPS) score of 2 or 3 in all three segments. Secondary measures included the Bubble Scale (BS) and adenoma detection rate (ADR).
Results showed no statistically significant difference between the two groups in adequate bowel preparation (95.8% vs 97.6%, P = 0.276) or ADR (22.3% vs 25.6%, P = 0.561). Both regimens were well tolerated, with similar rates of minor adverse effects such as bloating or nausea, assessed using a standardised patient questionnaire.
Clinical implications
Lead author Dr Xiaoyu Cai and colleagues concluded that 200 mg of simethicone provides comparable cleansing efficacy and lesion detection to the higher dose, making it a cost-effective and patient-friendly alternative for routine colonoscopy preparation.
The study reinforces the importance of dose optimisation in endoscopic practice, highlighting that lower doses can achieve equivalent clinical outcomes when combined with standard PEG-ELS preparation.
Reference
Cai X et al. Comparative efficacy of 200 mg versus 1200 mg of simethicone with 3 L polyethylene glycol electrolyte solution for afternoon colonoscopy: a randomized controlled trial. BMC Gastroenterol. 2025;DOI: 10.1186/s12876-025-04215-0.
