GLP-1 receptor agonists (GLP-1 RAs) are now routinely encountered in preoperative assessment. Their effect on gastric emptying raises concern about pulmonary aspiration risk during anesthesia. Five major professional bodies have published perioperative guidance since 2023, reaching divergent conclusions on four clinically important questions. A systematic search of PubMed, MEDLINE, Embase, professional society websites, and grey literature was conducted for perioperative GLP-1 RA guidelines published between January 2023 and March 2026. Five documents met eligibility criteria. Each was independently appraised by two reviewers using the AGREE-REX framework, and primary studies underpinning the guidelines were reviewed for four pre-specified clinical questions. Four of five guidelines now recommend drug continuation with structured fasting modification, superseding the 2023 American Society of Anesthesiologists (ASA) cessation policy. Fasting protocols diverge substantially: SPAQI 2025 uniquely distinguishes high-calorie from low-calorie liquids. Three of five documents explicitly state that absence of gastrointestinal symptoms cannot be relied upon for risk stratification. All five guidelines endorse gastric ultrasound but none define validated decision thresholds. AGREE-REX appraisal identified the Anesthetists of Great Britain and Ireland (AAGBI)/Royal College of Anesthetists (RCoA) 2025 statement as having the broadest multidisciplinary representation and the most transparent process; Society for Perioperative Assessment and Quality Improvement (SPAQI) 2025 had the most rigorous evidence base but the most complex implementation requirements. Endocrinologist and obesity medicine representation is absent from most authoring groups, and the recommendations reflect this. International guidelines share a direction, to continue with modified fasting, but the operational details remain contested. The clinical risks of incomplete gastric emptying, hypoglycemia in insulin-dependent patients, and the absence of validated gastric ultrasound decision thresholds are not yet adequately reflected in most guidance. Prospective outcome data capturing aspiration events and glycemic complications remain urgently needed.
