Fasting Instructions 

It is important for your safety that you follow these instructions. 

In preparation for your anaesthetic, you will be asked to stop eating and drinking for a period of time. This is known as the fasting period. The fasting period for food is different to that of clear fluids and water.  

It is vitally important that you follow the fasting information given to you to ensure you have an empty stomach. Food or fluid in the stomach may be regurgitated or vomited and enter your lungs while you are unconscious. This is called aspiration and can be a life-threatening complication of general anaesthesia or sedation. 

Standard fasting times are suitable for most people and procedures. However, new diabetic and weight-loss medications work by slowing stomach emptying and for safety require a longer period of fasting. 

If you do not follow the appropriate fasting guidelines, your procedure may be postponed in the interests of your safety.  

For safety, make your last meal before starting the fasting period a light meal only. 

IF YOU ARE HAVING A COLONOSCOPY, IN THE DAYS LEADING UP TO YOUR PROCEDURE, YOU MUST FOLLOW THE INSTRUCTIONS PROVIDED BY YOUR GASTROENTEROLOGIST. 

IF YOU HAVE BEEN TAKING GLP-1 TYPE MEDICATION (e.g. Ozempic, Wegovy, Mounjaro, Saxenda, Victoza, Trulicity, Retatrutide) YOU MUST FOLLOW THE EXTENDED FASTING INSTRUCTIONS BELOW unless you have ceased these medications more the 4 weeks prior to your procedure date. 

Standard fasting guidelines are listed below. If you have specific questions or special circumstances, please contact your anaesthetist and follow their directions. 

Standard fasting for ADULTS not taking diabetic/weight-loss GLP-1 type medications 

  • Do not eat any food for 6 hours prior to your admission time for your procedure/surgery. 
  • Do not drink any fluids for 6 hours prior to your admission time EXCEPT small sips of water (refer below) of up to 150 mls per hour until 2 hours prior to your admission time for surgery. 

For example:  

  • If your admission time for your procedure/surgery is scheduled for 8am, you should be fasting from 2am, and you can sip water until 6am. You should not consume any food or drink from 6am until your procedure, except as advised by medical staff. 
  • If your admission time for your procedure/surgery is 2pm, you can eat a light breakfast but must be finished by 8am, and you can sip water until midday.  You should not consume any food or drink from midday until your procedure, except as advised by medical staff. 

Fasting for ADULTS who are taking diabetic/weight-loss GLP-1 type medications 

GLP-1 medications include Ozempic, Wegovy, Mounjaro, Saxenda, Victoza, Trulicity, Retatrutide (Semaglutide; Tirzepatide; Liraglutide; Dulaglutide) and require a 24-hour clear fluid diet followed by 6 hours of fasting from ALL foods and liquids. Please note: new GLP-1 medications are soon being added to the health sphere so the GLP-1 examples above may not be all-inclusive.  

You must stop eating all food 30 hours prior to your admission time for your procedure/surgery, and then only have clear fluids (refer below). 

You must stop drinking clear fluids 6 hours prior to your admission time for your procedure/surgery.  For these last 6 hours, you cannot eat or drink anything including water.  However, you may have a few sips of water if you need to take medication. 

For example:  

  • If your admission time for surgery is scheduled for 8am Wednesday, you must stop eating all solid food from 2am Tuesday. You can have clear fluids only from 2am Tuesday until 2am Wednesday.  From 2am on Wednesday until your procedure you cannot eat or drink anything. 
  • If you follow the above fasting instructions, you may continue to take your GLP-1 medication as usual, including on the day of your procedure 
  • If you have ceased GLP-1 medications for four weeks or longer before your procedure date, you can follow the standard fasting instructions. 

Clear Fluids 

Clear fluids are any liquid that does not contain visible particles and can be seen through when held up to light.  

  • Permitted: Water, fruit juices without pulp, clear cordials, soft drink, black tea (no milk), black coffee (no milk), herbal tea, sports drinks such as Gatorade. 
  • Not Permitted: Milk, milk-based drinks, tea or coffee with milk, cloudy fruit juices, jelly, alcohol, and any liquids with pulp or particles.