Semaglutide (Ozempic, Wegovy)

Anesthesia Implications

Classification: Long-acting glucagon-like peptide-1 receptor agonists (GLP1-RA)
Therapeutic Effects: Treatment of type 2 diabetes mellitus (T2DM) and obesity

Duration: Half-life: 7days

Primary Considerations

Delayed Gastric Emptying – This drug is known to cause delayed gastric emptying, which may necessitate longer durations of fasting than those typically recommended. Diabetics, in general, are known to have delayed gastric emptying, but Semaglutide exacerbates the problem.

Increased Risk of Aspiration – Due to the point discussed above, patients on Semaglutide are at an increased risk of aspiration.

Changes in Fasting Guidelines – The ASA recommends for patients on daily dosing to consider holding GLP-1 agonists on the day of the procedure/surgery. For patients on weekly dosing consider holding GLP-1 agonists a week prior to the procedure/surgery. This recommendation is irrespective of the indication (type 2 diabetes mellitus or weight loss), dose, or the type of procedure/surgery. However, caution should be taken as Semaglutide has a half-life of 1 week – which would suggest gastroparesis/gastric slowing could exist well beyond (~ 5 weeks) the recommended times.

Possible Recommendations – In addition to the recommendations by the ASA, some studies have shown that placing the patient on a liquid diet 36 hours prior to the procedure will sufficiently empty the stomach prior to the procedure (even without discontinuing Semaglutide). Placing the patient on prokinetic drugs such as metoclopramide may also be helpful.

Preoperative Discontinuance Considerations – As mentioned, the half-life of Semaglutide is roughly 1 week, which to some may suggest discontinuance for ~5 weeks prior to the surgery. This would potentially lead to poor glycemic control. For that reason, the ASA suggests that the patient consult with an endocrinologist if the plan is to discontinue the medication any longer than the current recommendations.

Method of Action

Semaglutide specifically attaches to and stimulates receptors for glucagon-like peptide-1, which leads to elevated insulin levels and reduced release of glucagon.

Additional Notes
Semaglutide has gained popularity as a drug used to lose weight. Delayed gastric emptying is the culprit for this – the patient will feel full for a longer period of time, which leads to less caloric intake.

Fujino. Anesthesia Considerations for a Patient on Semaglutide and Delayed Gastric Emptying. 2023. web link
Friedrichsen. The effect of semaglutide 2.4 mg once weekly on energy intake, appetite, control of eating, and gastric emptying in adults with obesity. 2021.
Joshi. American Society of Anesthesiologists Consensus-Based Guidance on Preoperative Management of Patients (Adults and Children) on Glucagon-Like Peptide-1 (GLP-1) Receptor Agonists. 2023. web link