PATIENT INFORMATION
Pre-operative Fasting Guidelines
Eating and drinking instructions before anaesthesia, including sedation.
Fasting before a procedure is important for your safety. These guidelines apply to all forms of anaesthesia, including sedation, general anaesthesia, spinal or epidural anaesthesia and nerve blocks.
Follow your instructions
Your hospital, surgeon or anaesthesiologist may give you specific fasting times.
Clear fluids are different
Clear fluids are allowed closer to surgery than food or dairy.
Medication matters
Some medicines and medical conditions may change your fasting instructions.
Adults
Adults may drink clear fluids up to two hours before elective surgery (max 200 - 250ml per hour), unless told otherwise. Food, dairy and particulate fluids up to six hours before surgery.
Children
Children may be encouraged to drink clear fluids up to two hour before elective surgery (max 3ml/kg per hour). Breastmilk may be consumed up to four hours before surgery and all food, puree, dairy, formula up to six hours before surgery.
Not everything counts as clear fluid
Jelly, sweets and smoothies are not treated as clear fluids before surgery.
GLP-1 medicines
Medication such as Ozempic or Mounjaro do require adjusted (often longer) fasting times.
WHY FASTING MATTERS
Why can’t I eat or drink before surgery?
An empty stomach reduces the chance of aspiration and its complications. Aspiration happens when stomach contents move back up the oesophagus and enter the lungs.
Aspiration can cause significant lung damage. Following your fasting instructions carefully is one of the ways you can help reduce this risk.
Important to remember
- Fasting instructions apply to all forms of anaesthesia, including sedation.
- Do not assume your procedure is exempt because you are not having a general anaesthetic.
- Only take medication on the morning of surgery if you have been told to do so.
- Necessary medication may usually be taken with a small sip of water, but confirm this with your doctor.
STANDARD GUIDELINES
Clear fluid fasting times
Adults
Adults may drink clear fluids (max 200-250ml per hour) up to two hours before elective surgery, unless they have been given different instructions.
Clear fluids include water, pulp-free juice, and tea or coffee without milk.
Children
Unless contraindicated, children should be encouraged to drink clear fluids (max 3ml/kg per hour) until two hours before elective surgery.
Clear fluids include water, pulp-free juice, and tea or coffee without milk.
Always follow the instructions you are given
These are general guidelines. Your anaesthesiologist, surgeon or hospital may give you different instructions depending on your procedure, medical history, medication or aspiration risk.
WHAT COUNTS?
Clear fluids, food and common misunderstandings
A clear fluid is a liquid that you can see through. Examples include water, pulp-free juice, and tea or coffee without milk.
Some items that patients think of as “light” are still treated as food or solids for fasting purposes.
Little-known fasting rules
- Jelly is not considered a clear fluid.
- Sweets are considered solid food.
- Smoothies are considered solid food.
- Tea or coffee with milk is not considered a clear fluid.
- Juice with pulp or particles is not considered a clear fluid.
Some patients need extra precautions
Pre-existing medical conditions can affect how quickly the stomach empties and may increase aspiration risk. This includes conditions such as delayed gastric emptying in diabetes and gastro-oesophageal reflux disease.
Please tell your anaesthesiologist about your medical conditions, previous anaesthetic problems, reflux symptoms and all medication you take, including prescribed, over-the-counter and injectable medication.
GLP-1 MEDICINES
Ozempic, Mounjaro and similar medication
GLP-1 receptor agonist medication, such as Ozempic and Mounjaro, can delay stomach emptying. This may increase the risk of stomach contents entering the lungs during anaesthesia or sedation.
You will be required to follow adjusted (often longer) fasting times. In some cases, patients may be asked to omit medication before surgery.
Please tell us if you use these medications
- Ozempic
- Mounjaro
- Wegovy
- Saxenda
- Trulicity
- Victoza
- Any other diabetes or weight-loss injection or tablet
Do not stop medication without advice
If you take a GLP-1 receptor agonist or any diabetes medication, please ask your surgeon, anaesthesiologist or prescribing doctor what to do before your procedure. Stopping medication may also carry risks, so instructions should be individualised.
PRACTICAL CHECKLIST
Before your procedure
Confirm your fasting time
Make sure you know when to stop eating, when to stop milk or non-clear liquids, and when to stop clear fluids.
Ask about medication
Check which medication you should take, which should be omitted, and whether anything should be taken with a sip of water.
Tell the team about risk factors
Mention reflux, diabetes, delayed gastric emptying, GLP-1 medication, nausea, vomiting or any recent illness.
MORE DETAIL
Common fasting questions
Can I take my medication on the morning of surgery?
Necessary medication may usually be taken with a small sip of water, but this should be confirmed with your surgeon, anaesthesiologist or hospital team.
Blood-thinning medication, diabetes medication and GLP-1 receptor agonists need special consideration.
Does fasting apply if I am only having sedation?
Yes. Fasting policies apply to all forms of anaesthesia, including sedation. Even with sedation, protective reflexes and breathing may be affected, so fasting remains important.
What happens if I eat or drink too close to surgery?
Please tell the hospital or anaesthesiologist honestly. Your procedure may need to be delayed or your anaesthetic plan may need to change to reduce the risk of aspiration.
Is jelly a clear fluid?
No. Jelly is not considered a clear fluid for fasting purposes.
Are sweets allowed before surgery?
No. Sweets are considered solid food for fasting purposes.
Are smoothies allowed as clear fluids?
No. Smoothies are considered solid food because they contain particles, fibre, dairy or other ingredients that are not treated as clear fluids.
Unsure what you may eat, drink or take?
Please contact the hospital, surgeon or anaesthesiology practice before eating, drinking or taking medication if you are unsure.
It is safer to ask than to risk your procedure being delayed or your anaesthetic plan needing to change on the day.
NEED HELP?
Still have questions?
Contact the practice if you are unsure about your fasting instructions, medication or what applies to your procedure.
