A study of 47,039 surgical patients across 119 UK hospital sites has found that people taking GLP-1 receptor agonists, including semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro), were around 11 times more likely to regurgitate stomach contents or inhale them into their lungs during anaesthesia than patients not on these medicines. The research, led by Dr Kariem El-Boghdadly of Guy's and St Thomas' NHS Foundation Trust and King's College London through the GLIMPSE resident research network, was presented at the Association of Anaesthetists Annual Meeting in Liverpool on 16 September 2026 and published in the journal Anaesthesia. Of 1,348 patients on a GLP-1 medicine, 19 (1.41%) had a regurgitation or aspiration event, compared with 57 of 45,691 patients (0.12%) who were not taking one. Most events happened as patients were coming round from anaesthesia, when airway reflexes have not fully returned.
What the researchers say the finding does and does not show
The study authors were explicit that it cannot prove GLP-1 medicines caused the extra risk. Patients taking them were more likely to also have obesity and type 2 diabetes, both of which independently slow stomach emptying and raise aspiration risk during anaesthesia, so some of the association may reflect these underlying conditions rather than the drug itself. The team also relied on clinician-reported events, which may undercount milder episodes, and cautioned that findings from these UK sites may not generalise everywhere. No funding source for the analysis was disclosed in the reporting reviewed for this article.
What this means for your supplement routine
This is a finding about prescription-only weight loss and diabetes medicines, not about food supplements, and Perqen does not sell or advise on GLP-1 medicines. It is a reminder that any medicine affecting appetite or digestion is worth mentioning to an anaesthetist or surgical team before a procedure, a point the study's own authors highlighted rather than one we are making as advice. For anyone reviewing what else is already in a supplement routine, current prices across the wider catalogue are on the full product catalogue.
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This article reports published news and research and is for information only. Food supplements are not a substitute for a varied diet or medical care, and no product mentioned is intended to diagnose, treat, cure or prevent any disease. Speak to your GP or pharmacist before changing what you take, especially if you are pregnant, breastfeeding, or taking prescribed medicines.