Remimazolam is a new ultra-short-acting benzodiazepine with a favorable safety-profile when used for sedation in endoscopy. The aim of this project was to investigate efficacy of remimazolam with fentanyl compared with midazolam with fentanyl for sedation in colonoscopy among fecal immunochemical test (FIT)-positive screening participants.

The study was a prospective, single-blinded, randomized controlled trial. FIT-positive participants undergoing colonoscopy were randomized to intravenous remimazolam + fentanyl (RF) or midazolam + fentanyl (MF). Primary outcome was total time from start of medication until discharge. Secondary outcomes included time to reach cecum, need for post-procedure recovery, patient-reported pain and satisfaction, need for additional medication, and procedure completion.

A total of 205 patients were included and randomized 1:1 (RF:103, MF:102). Mean age was 62.6 years, whereas female/male ratio was 97/108. Mean time from start of medication until discharge was 29.9 minutes (RF) versus 35.0 minutes (MF) (95% confidence interval 0.77–0.94, P = 0.012). Mean time to reach the cecum was 15.4 minutes (RF) compared with 20.2 minutes (MF) (P = 0.001). Proportion of patients requiring postoperative observation was lower for RF 0.97% vs 9.8% for MF (P = 0.022). Patients receiving remimazolam reported an average lower pain score (mean 2.25 (RF) vs 3.25 (MF) P = 0.012) and higher overall satisfaction score (4.65 vs 4.33, P = 0.012).

This study shows clear superiority of the combination of remimazolam with fentanyl over midazolam with fentanyl for conscious sedation in screening colonoscopy, obtaining shorter procedure time, less postoperative need for observation, lower patient pain scores, and higher patient satisfaction.

Received: 09 October 2024

Accepted after revision: 26 May 2025

Accepted Manuscript online:
14 July 2025

Article published online:
15 August 2025

© 2025. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/).

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Bibliographical Record
Andrea C Armbrecht, Bojan Kovacevic, Maria Dyrehave Rasmussen, Michelle Katharina Bernth, Ann Merete Moeller, Peter Vilmann. Efficacy of remimazolam with fentanyl vs midazolam with fentanyl for sedation in screening colonoscopy: Randomized controlled study. Endosc Int Open 2025; 13: a26551083.
DOI: 10.1055/a-2655-1083