Warning on weight-loss injections and peptides for patients having surgery
Australian and New Zealand College of Anaesthetists
MONDAY 5 OCTOBER 2026
People using popular GLP-1 weight-loss injections and peptides are being urged to alert their anaesthetist before surgery because their stomach may still contain food, a complication that can have potential life-threatening consequences.
The warning comes from the Australian and New Zealand College of Anaesthetists (ANZCA) ahead of National Anaesthesia Day on Friday 16 October.
ANZCA President Dr Tanya Selak says patients should not assume that GLP-1 RA (glucagon-like peptide-1 receptor agonists) injections or other peptides are irrelevant to their anaesthesia care.
“These medications can slow the emptying of the stomach which may still contain food or other material even when you have followed the usual fasting instructions. We know of some rare cases where the consequences of stomach contents entering the lungs during surgery (pulmonary aspiration) can be extremely serious and life-threatening for patients.
“Your anaesthetist needs to know if you are taking these medications so they can assess the safest approach for your procedure,” she explains.
“If you are using a weight-loss peptide or GLP-1 medication, please tell your anaesthetist. It is important that we know exactly what you are taking, when you last took it and why you are taking it.”
Amid concerns about the number of Australians injecting themselves with unapproved performance and image-enhancing drugs purchased online the Therapeutic Goods Administration recently announced new compliance measures targeting suppliers and manufacturers selling unapproved products.
While anaesthetists have updated their fasting guidelines for patients preparing for surgery to allow clear liquids until patients are called to theatre, people taking GLP-1 or peptides may require different instructions because of delayed stomach emptying. For example, they could be told to extend the period of fluids-only fasting to the day before.
ANZCA's patient information now generally allows small amounts of clear liquids until patients are called to theatre, while solid food and non-clear fluids should stop six hours before elective surgery.
The warning from anaesthetists comes as the use of GLP-1 medicines and other weight-loss peptides continues to grow.
New UK research reported in the journal Anaesthesia last month found that the rate of regurgitation of stomach contents is 11 times more likely to occur in patients taking GLP-1s than in patients not taking those drugs – although the absolute risk remains small.
Dr Selak says current advice is that patients should not stop their medication without medical advice.
“The important message for patients is not to stop your medication on your own. Instead, make sure your surgical and anaesthesia team knows that you are taking it so they can provide individual advice about fasting and your anaesthetic.”
ANZCA’s new National Anaesthesia Day resources for patients on “Fasting before your surgery” are now available on the college website.
Dozens of hospital anaesthesia departments in Australia and New Zealand will be celebrating National Anaesthesia Day on 16 October with patient displays and events that highlight the specialty.
Contact details:
For more information or to request interviews, please contact ANZCA Media Manager Carolyn Jones on +61 3 8517 5303, +61 408 259 369 or [email protected]