GLP-1 weight-loss drugs linked to increased risk of pulmonary aspiration during surgery

Research suggests patients taking GLP-1 weight-loss medications may face a higher chance of serious breathing complications during surgery due to delayed gastric emptying, prompting calls for cautious pre-operative planning.

Patients taking GLP-1 weight-loss drugs may face a higher risk of a rare but serious complication during surgery, according to researchers at Guy’s and St Thomas’ and King’s College London. Their analysis found that people using these medicines were more likely to experience pulmonary aspiration under general anaesthesia, a problem in which stomach contents enter the lungs and can trigger severe breathing complications.

The findings fit with a safety update from the UK Medicines and Healthcare products Regulatory Agency, which has warned that GLP-1 and dual GIP/GLP-1 receptor agonists, including tirzepatide, can slow gastric emptying. That means food may remain in the stomach even when patients have followed standard fasting instructions before an operation. The BMJ has also reported the agency’s advice that patients should tell their surgical team if they are taking one of these drugs.

In the British study, published after reviewing records from 47,039 patients at 119 NHS hospitals, complications were recorded in 1.4% of drug users compared with 0.12% of non-users. The relative increase was striking, but the researchers emphasised that the absolute risk remained low. They also noted an important complication: obesity and diabetes themselves can raise the chance of perioperative problems, making it difficult to separate the effect of the medication from the conditions for which many patients take it.

That uncertainty helps explain why guidance remains uneven. The British Journal of Anaesthesia has reported that some clinicians advise patients to stop GLP-1 drugs before surgery, while UK guidance has so far stopped short of recommending routine discontinuation because evidence that a temporary pause reduces risk is still limited, particularly for people with diabetes. For dentists and other clinicians using sedation, the broader message is the same: these medicines are becoming more common, and careful pre-operative planning is increasingly important.