Ozempic Before Surgery? A New Study Raises Questions About a Hidden Anesthesia Risk

About 1 in 8 U.S. adults now report taking a GLP-1 medication for weight loss, diabetes, or another medical condition, putting drugs such as Ozempic, Wegovy, Mounjaro, and Zepbound into millions of medicine cabinets.

But as these medications become more common, doctors are facing a newer question before surgery: could a drug that slows digestion change what happens when a patient goes under anesthesia?

A new UK study found that people taking GLP-1 medications had a higher rate of regurgitation or pulmonary aspiration events during anesthetic care compared with people who were not taking the drugs. The finding sounds alarming, but researchers and medical societies stress that the overall number of events was still small, and the study does not prove the medications caused them.

The takeaway for patients is not to stop their medication on their own. It’s to make sure their surgical team knows exactly what they are taking.

What The New Study Found

The study, published in Anaesthesia in September 2026, followed more than 47,000 patients receiving anesthetic care across multiple UK centers. Researchers compared outcomes among 1,348 GLP-1 users and 45,691 non-users.

Among GLP-1 users:

19 experienced regurgitation or pulmonary aspiration events.
That represented an event rate of 1.41%, compared with 0.12% among non-users.
The researchers calculated that the combined outcome was associated with about an 11-fold higher rate among GLP-1 users.

But that number needs context.

The 19 events were not all cases of food entering the lungs. Seventeen involved regurgitation, while two involved pulmonary aspiration.

That difference matters because regurgitation and aspiration are related but not identical. Regurgitation means stomach contents come back up into the throat. Aspiration happens when material enters the lungs, which can lead to complications such as lung inflammation or pneumonia.

The study authors also emphasized that an association does not prove cause and effect. Other factors (including obesity, diabetes, and other health differences among people taking GLP-1 drugs) may have influenced the results.

Why GLP-1 Drugs Could Affect Anesthesia

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Normally, fasting before surgery reduces the amount of food or liquid in the stomach. But if digestion is slowed, some patients may still have residual stomach contents despite following standard fasting instructions.

This matters because anesthesia can temporarily reduce the body’s normal protective airway reflexes. If stomach contents move upward and enter the lungs, there is a risk of pulmonary aspiration.

The issue is not that every person taking Ozempic or another GLP-1 drug has a dangerous amount of food remaining in their stomach. The issue is that some patients may need a more individualized approach before anesthesia.

Related: As England Bans Fried Foods in Schools to Curb Obesity, America Turns to GLP-1s for Teens

The “11-Fold Risk” Needs Context

Relative risks can sound dramatic without showing the full picture.

In this study, the absolute difference was:

About 1 in 71 GLP-1 users experienced regurgitation or aspiration.
About 1 in 802 non-users experienced the same combined outcome.

That does not mean 1 in 71 people taking Ozempic will aspirate during surgery. Most GLP-1 users in the study did not experience these events.

It also does not mean the medication alone explains the difference. Researchers cannot determine from this type of observational study whether the drug itself caused the higher event rate.

The Research Is Still Evolving

The new UK findings add to a growing debate, but they are not the only evidence doctors are considering.

Other studies have looked at different outcomes and reached different conclusions. For example, research examining postoperative aspiration pneumonia has not consistently found the same increase seen in the UK study’s combined regurgitation and aspiration measure.

Partly because researchers are measuring different things.

A regurgitation event during anesthesia is not the same as developing aspiration pneumonia days later. Different procedures, patient groups, and definitions can produce different results.

What Current Guidance Says Before Surgery

Despite the new findings, current U.S. guidance does not tell every GLP-1 user to stop medication before surgery.

The American Society of Anesthesiologists says most patients can continue GLP-1 medications before elective procedures. Instead, doctors should assess individual risk and decide whether extra precautions are needed.

Patients may need additional precautions if they:

Recently started the medication or are increasing their dose.
Have nausea, vomiting, bloating, constipation, or abdominal pain.
Take higher doses associated with more gastrointestinal side effects.
Have another condition that slows stomach emptying.

For higher-risk patients, clinicians may recommend a 24-hour liquid-only diet, adjust the anesthesia approach, use stomach ultrasound before the procedure, or delay elective surgery in uncommon cases.

The One Thing Patients Should Do Before Surgery

The most important step is simple: tell your medical team you take a GLP-1 drug.

That includes:

Whether you recently increased the dose.
Any digestive symptoms such as nausea, vomiting, bloating, constipation, or abdominal pain.

Patients should not stop injections or tablets without medical advice. For people taking GLP-1 drugs for diabetes, stopping suddenly can affect blood sugar control, and unnecessary interruptions can create other treatment challenges.

The bigger story is not that GLP-1 drugs make surgery unsafe. It’s that these medications have become common enough that anesthesia teams now need a clearer picture of who may need extra precautions, and who can safely continue treatment as planned.

Should taking a GLP-1 medication become as routine a part of pre-surgery screening as telling doctors about other medications?