GLP-1 receptor agonist use in gastrointestinal endoscopy: A review of current evidence and guidelines

The use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) has increased over the past several years and has become a cornerstone in both diabetes and weight loss management, particularly because of its unique combination of glucose control, weight reduction potential, and cardiac and metabolic benefits. However, increased use of these agents presents a dilemma in gastrointestinal endoscopy as it pertains to their safety and management during the periprocedural period.

This review explores management of GLP-1 RAs in the periprocedural setting for endoscopic procedures based on current evidence and guidelines, highlighting gaps and future directions.

Pharmacology and Mechanisms of Action

GLP-1 RAs have several mechanisms of action that make them relevant in gastrointestinal endoscopy. These medications modulate glucose control via enhancement of glucose-dependent insulin secretion and reduction of postprandial glucagon, which promotes satiety and delays gastric emptying. This delay in gastric emptying mediated by vagal pathways has been postulated to increase gastric residuals, posing a risk for aspiration during anesthesia.¹

It is important to also consider the pharmacokinetics of GLP-1 RAs, as some have shorter half-lives on the order of several hours, like exenatide, while others, like semaglutide, are dosed weekly. Additionally, common side effects of GLP-1 RAs include nausea, vomiting, bloating, and early satiety, which pose challenges for patients undergoing endoscopic procedures. 

Current Guidelines

Various societies have published guidelines on the periprocedural use of GLP-1 RAs. The American Society of Anesthesiologist (ASA) in 2023 presented early recommendations to hold GLP-1 RAs either day of procedure or week prior depending on pharmacokinetics, because of the risk of delayed gastric emptying and increased potential for aspiration.² Soon thereafter, a multi-gastroenterology society guideline was released stating more data is needed to decide if GLP-1 RAs need to be held prior to endoscopic procedures.³

In early 2024, the American Gastroenterological Association (AGA) published a rapid clinical update that advocated for a more individualized approach, particularly in light of limited overall data for GLP-1 RAs and endoscopic procedures.⁴ In asymptomatic patients who follow typical fasting protocols for procedures, it is generally safe to proceed with endoscopy without holding GLP-1 RAs. In symptomatic patients (nausea, abdominal distension, etc), the AGA advises additional precautions, including performing transabdominal ultrasound if feasible to assess retained gastric contents. The AGA also suggests placing a patient on a clear liquid diet the day prior to the procedure — rather than holding GLP-1 RAs — as another reasonable strategy.

The guidelines continue to evolve with newer multi-society guidelines establishing best practices. While initially in 2023 the ASA did recommend holding these medications prior to endoscopy, the initial guidance was based on expert opinion with limited evidence. Newer multi-society guidance published jointly by the ASA along with various gastroenterology societies, including the AGA in December 2024, takes a more nuanced approach.⁵

The newer guidelines include two main recommendations:

1. Periprocedural management of GLP-1 RAs should be a joint decision among the procedural, anesthesia, and prescribing team balancing metabolic needs vs patient risks.

• In a low-risk patient, one that is asymptomatic and on standard dosing, among other factors, the guidance states that GLP-1 RAs can be continued.

• In higher-risk patients, the original guidance of holding a day or a week prior to endoscopic procedures should be followed.

2. Periprocedural management of GLP-1 RAs should attempt to minimize the aspiration risks loosely associated with delayed gastric emptying.

• Consider a 24-hour clear liquid diet a day prior to the procedure and transabdominal ultrasound to check gastric contents.

• It is acknowledged that this guidance is based on limited evidence and will be evolving as new medications and data are released.

Recent Clinical Studies

Although there is very little data to guide clinicians, several recent studies have been published that can direct clinical decision-making as guidelines continue to be refined and updated.

A multicenter trial of approximately 800 patients undergoing upper endoscopy found a significant difference in rates of retained gastric contents between those that underwent endoscopy who did and did not follow the ASA guidance on periprocedural management of GLP-1 RAs (12.7% vs 4.4%; P < .0001). However, there were no significant differences in rates of aborted procedures or unplanned intubations.

Furthermore, a multivariable analysis was performed controlling for GLP-1 RA type and other factors, which found the likelihood of gastric retention increased by 36% for every 1% increase in hemoglobin A1c. This study suggests that a more individualized approach to holding GLP-1 RA would be applicable rather than a universal periprocedural hold.⁶

More recently, a single-center study of nearly 600 patients undergoing upper endoscopy showed that while there were slightly increased rates of retained gastric contents (OR 3.80; P = .003) and aborted procedures (1.3% vs 0%; P = .02), the rates of adverse anesthesia events (hypoxia, etc) were similar between the groups and no cases of pulmonary aspiration were noted.7

One single-center study of 57 patients evaluated the safety of GLP-1 RAs in those undergoing endoscopic sleeve gastrectomy. GLP-1 RAs were continued on all patients, but all adhered to a liquid only diet for at least 24 hours prior to the procedure. There were no instances of retained gastric solids, aspiration, or hypoxia. This study suggests that with a 24-hour clear liquid diet and routine NPO recommendations prior to endoscopy, it would be safe to continue GLP-1 RAs. This study provides rationale for the AGA recommendation for a clear liquid diet 24 hours prior to endoscopic procedures for those on GLP-1 RAs.⁸

A study looking at those who underwent emergency surgery and endoscopy with claims data of use of GLP-1 RAs found an overall incidence of postoperative respiratory complications of 3.5% for those with GLP-1 RAs fill history vs 4.0% for those without (P = .12). Approximately 800 of the 24,000 patients identified had undergone endoscopic procedures for GI bleeding or food impaction. The study overall showed that preoperative use of GLP-1 RAs in patients undergoing surgery or endoscopy, evaluated as a combined group, was not associated with an increased risk of pulmonary complications.⁹

Lastly, a systematic review and meta-analysis that included 15 studies that quantified gastric emptying using various methods, including gastric emptying scintigraphy and acetaminophen absorption test, found that there was a quantifiable delay in gastric emptying of about 36 minutes, compared to placebo (P < .01), in patients using GLP-1 RAs. However, compared to standard periprocedural fasting, this delay is clinically insignificant and standard fasting protocols would still be appropriate for patients on GLP-1 RAs.¹⁰

These studies taken together suggest that while GLP-1 RAs can mildly increase the likelihood of retained gastric contents, there is no statistically significant increase in the risk of aspiration or other anesthesia complications. Furthermore, while decreased gastric emptying is a known effect of GLP-1 RAs, this effect may not be clinically significant in the context of standard periprocedural fasting protocols particularly when combined with a 24-hour clear liquid diet. These findings support at a minimum a more patient-specific strategy for periprocedural management of GLP-1 RAs.

Clinical Implications

These most recent studies, as well as prior studies and guidelines by various societies lead to a dilemma among endoscopists on proper patient counseling on GLP-1 RAs use before endoscopic procedures. Clinicians must balance the metabolic benefits of GLP-1 RAs with potential endoscopic complications and risks.

Holding therapy theoretically decreases aspiration risk and pulmonary complications, though evidence remains low to support this. Holding medication, however, affects glycemic control leading to potential rebound hyperglycemia which may impact and delay plans for endoscopy. With growing indications for the use of GLP-1 RAs, a more tailored patient-centered treatment plan may be required, especially with consideration of procedure indication and comorbidities.

Currently, practice patterns at different institutions vary widely, making standardization much more difficult. Some centers have opted to follow ASA guidelines of holding these medications up to 1 week prior to procedures, while others have continued therapy with no pre-procedural adjustments. This leaves endoscopists to deal with the downstream effects of inconvenience to patients, care delays, and financial considerations if procedures are postponed related to GLP-1 RAs use.

Future Directions

Future studies are needed to make further evidence-based recommendations. Studies should focus on stratifying risks and recommendations based on procedure type (EGD, colonoscopy, etc). More widespread implementation of gastric ultrasound can assist in real-time decision-making, albeit this would require expertise and dedicated time within the pre-procedural workflow. Randomized controlled trials comparing outcomes of patients who continue GLP-1 RAs vs those who discontinue stratified by baseline risk will be instrumental for making concrete guidelines that provide clarity on periprocedural management of GLP-1 RAs.

Conclusion

The periprocedural management of GLP-1 RAs remains a controversial topic that presents unique challenges in endoscopy. Several guidelines have been released by various stakeholders including anesthesiologists, gastroenterologists, and other prescribing providers. Clinical data remains limited with no robust evidence available to suggest that gastric emptying delays caused by GLP-1 RAs prior to endoscopic procedures significantly increases risk of aspiration, pulmonary complications, or other comorbidities. Evolving multi-society guidelines will be important to establish more consistent practices with reassessment of the data as new studies emerge. A multidisciplinary, individualized patient approach may be the best strategy for managing GLP-1 RAs for patients undergoing endoscopic procedures.

Dr. Sekar and Dr. Asamoah are based in the department of gastroenterology at MedStar Georgetown University Hospital, Washington, D.C. Dr. Sekar reports no conflicts of interest in regard to this article. Dr. Asamoah serves on the Johnson & Johnson advisory board for inflammatory bowel disease–related therapies.