Simethicone dosages with minimal normal saline solution volume to enhance mucosal visualization in upper endoscopy - a multicenter, randomized, double-blind, placebo-controlled trial

Q: What was the main goal of this trial?

To determine whether different simethicone doses, administered in minimal normal saline volume before EGD, improve mucosal visibility while maintaining patient safety and aligning with endoscopy and anesthesiology guidance.

Q: How were patients assigned and what were the intervention doses?

In this multicenter randomized double-blind placebo-controlled study, 268 patients were assigned to placebo or simethicone 40 mg, 80 mg, or 160 mg, each diluted in normal saline to a volume of 2.4 mL and given 15–30 minutes before EGD.

Sep 30, 2026

Uploaded by Jordan Avery

Premedication with simethicone before esophagogastroduodenoscopy (EGD) improves mucosal visibility, but the appropriate dose has been uncertain. This multicenter randomized double-blind placebo-controlled trial compared placebo with simethicone 40 mg, 80 mg, or 160 mg given 15–30 min before EGD, each diluted in minimal normal saline to 2.4 mL. Mucosal visibility from esophagus to duodenum was assessed with validated scoring; primary and secondary outcomes included procedure time, additional simethicone use, and patient satisfaction.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages9

Reading Time23 min

AccessFree to download

Results

Study population

Study outcomes

[www. nature.com/scientificreports](www. nature.com/scientificreports) OPEN Simethicone dosages with minimal normal saline solution volume to enhance mucosal visualization in upper endoscopy: a multicenter, randomized, double-blind, placebo-controlled trial Sereephap Saeung1, Thotsaporn Morasert2, Panakorn Wannawong1, Chayanis Kositamongkol3 & Pochamana Phisalprapa3􀀍 Premedication with simethicone before esophagogastroduodenoscopy improves mucosal visibility, but the appropriate dose remains unclear. This placebo-controlled trial compared 3 simethicone doses administered 15–30 min before esophagogastroduodenoscopy. In this randomized, double-blind, placebo-controlled, multicenter trial (1 June 2024–31 January 2025), 268 patients were assigned to placebo (n = 66) or simethicone (40 mg (n = 67) 80 mg (n = 67) or 160 mg (n = 68)) . Each dose was diluted with normal saline solution to 2.4 ml. Mucosal visibility from the esophagus to the duodenum was assessed using validated scoring systems. The primary outcome was the total mucosal visibility score, while the secondary outcomes were procedure duration, amount of additional simethicone required, and patient satisfaction. All simethicone groups had lower total mucosal visibility scores than placebo (9.9 ± 1.4, 10.1 ± 1.7, and 9.9 ± 1.2 vs 14.2 ± 2.7; P < 0.001) . No significant differences were observed among simethicone doses. Procedure durations were shorter in all simethicone arms (2.89–2.96 min) compared with placebo (3.63 min; P < 0.001). The additional simethicone administered was minimal in all simethicone groups, and patient satisfaction scores did not differ. Simethicone doses of 40, 80, and 160 mg with minimal normal saline solution improved mucosal visibility and modestly reduced procedure time compared with placebo. No dose-related differences were observed. Keywords Simethicone dosage, Esophagogastroduodenoscopy, Mucosal visibility, Premedication, Randomized controlled trial Esophagogastroduodenoscopy (EGD) is widely used to diagnose and treat gastrointestinal diseases1–4, yet excessive foam or bubbles can obscure the view even when fasting guidelines are followed5,6. Foam impairs accurate assessment, particularly of small lesions or lesions mimicking normal mucosa7,8. Endoscopists often flush water or normal saline solution (NSS) mixed with an antifoaming agent, such as simethicone, through the working channel to clear the field9. Although no substantive evidence links this cleansing method to increased pulmonary aspiration, preprocedural residual gastric content is a significant risk factor for aspiration with potential severe complications or death10–12. This risk is heightened when gastric volume exceeds 1.5 mL/kg (approximately 100 mL in an average adult)13. Excessive water flushing also prolongs procedures and may cause discomfort during and after EGD14. Trials15–19 administering simethicone 15–30 min before EGD—at doses of 40–100 mg in 30–100 mL—consistently improved mucosal visibility versus placebo. Nevertheless, guidance is inconsistent because the European Society of Gastrointestinal Endoscopy20 and the American Society for Gastrointestinal Endoscopy21 1Division of Gastroenterology, Department of Medicine, Surat Thani Hospital, Surat Thani 84000, Thailand. 2Division of Pulmonary and Critical Care Medicine, Department of Medicine, Surat Thani Hospital, Surat Thani 84000, Thailand. 3Division of Ambulatory Medicine, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand. 􀀍 email: [a.pochamana@gmail.com](a.pochamana@gmail.com) [www. nature.com/scientificreports/](www. nature.com/scientificreports/) do not endorse routine use. By contrast, the British Society of Gastroenterology and the Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland3, as well as Japanese principles22, recommend simethicone to enhance lesion detection. These discrepancies reflect regional variation

FAQs

What was the main goal of this trial?

To determine whether different simethicone doses, administered in minimal normal saline volume before EGD, improve mucosal visibility while maintaining patient safety and aligning with endoscopy and anesthesiology guidance.

How were patients assigned and what were the intervention doses?

In this multicenter randomized double-blind placebo-controlled study, 268 patients were assigned to placebo or simethicone 40 mg, 80 mg, or 160 mg, each diluted in normal saline to a volume of 2.4 mL and given 15–30 minutes before EGD.

Did higher simethicone doses produce better outcomes than placebo?

All simethicone groups had lower total mucosal visibility scores than placebo, and procedure durations were shorter in all simethicone arms. No significant differences were observed among the different simethicone doses, indicating no clear dose-related advantage.

Sep 30, 2026

Uploaded by Jordan Avery