Does this apply to me? This guidance is for patients taking medicines such as: semaglutide (Ozempic, Wegovy), tirzepatide (Mounjaro, Zepbound), dulaglutide (Trulicity), liraglutide (Saxenda, Victoza) and exenatide (Bydureon). If you take one of these, please follow this page rather than the standard fasting instructions.

Keep taking your medication

Do not stop your medication unless your doctor tells you to. Keep taking it as usual before your surgery. If you are unsure, contact your doctor or Dr Halvey's rooms before your operation.

Your fasting plan

In the time leading up to your surgery, follow these three stages. The aim is to have your stomach as empty as possible by the time of your anaesthetic.

When	What to do
24 to 6 hours before	Clear fluids only. You may have clear juice, clear sports drinks, clear broth, and black tea or coffee. No solid food during this time.
6 to 2 hours before	Water only. A maximum of 200 ml of water per hour.
2 hours before, until surgery	Nothing by mouth. No exceptions. This includes water.

What counts as a clear fluid

Water
Black tea or black coffee (no milk or cream)
Clear apple juice (no pulp)
Clear electrolyte drinks such as Hydralyte, Powerade or Gatorade
Clear broth or consommé (see below)

What is clear broth or consommé?

This means a plain, watery soup made only from strained meat or vegetables, with no solids and no cloudiness. You can use:

Store-bought clear chicken or beef broth, heated up
Powdered stock (for example Massel or Continental) mixed with hot water
Canned consommé, if it is fully clear

Do not use creamy, cloudy or chunky soups, such as pumpkin soup, chicken noodle soup, cream of chicken, or miso with bits.

Do not have during the clear fluid period

Milk or milk-based drinks
Soups with solids, fat or cream
Protein shakes such as Sustagen or Up & Go
Smoothies or meal replacements
Juices with pulp

If you have not been able to follow these instructions (for example, you have not kept to the clear fluid diet for 24 hours), it is important to tell your doctor or anaesthetist as early as possible. They may delay your surgery, use special techniques to reduce the risk during anaesthesia, or give you medication to help empty your stomach faster. It is always safer to tell us than to stay quiet.

Other important information

If you have a condition such as gastroparesis, Parkinson's disease, or bowel problems, your stomach may still empty slowly even if you have fasted correctly. Please tell your doctor or anaesthetist about this before your surgery.

Where this guidance comes from

This advice is based on the national guideline published in April 2025 and endorsed by ANZCA (the Australian and New Zealand College of Anaesthetists), the Australian Diabetes Society, GESA and NACOS. You can read the full guideline on the ANZCA website.

If you take Rybelsus tablets

Rybelsus (semaglutide tablets) follows the same fluid rules above, with one extra step: do not take your tablet on the morning of surgery. It is taken on an empty stomach with water and food afterwards, so it is skipped while fasting. Restart it when you are eating and drinking normally again.

Not sure whether this applies to you, or have a question about your medicines before surgery? Contact the rooms on (08) 6267 6200. Always follow the specific instructions given to you by Dr Halvey, your surgeon or the hospital.