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Fasting Guidelines

The doctor might give your child medicines to help them sleep through a surgery, procedure, test, or treatment. These medicines are called anesthesia. The procedure to give these medicines is called sedation.

Sometimes, your child must go without food or drink before sedation. Your child might also need to go without food or drink before certain procedures, scans, or tests without sedation.

Going without food before a test is called fasting. You might also hear it called NPO, which is short for Latin words that mean “nothing by mouth."

Why fasting is needed

There are several reasons your child may need to fast before a procedure or test:

  • If a child vomits while sedated, food or liquid in their stomach could get into the lungs. This could cause pneumonia or other serious health problems.
  • Food can hide issues in some types of scans.
  • Some scans or tests require avoiding certain foods.
  • Your child might also need to drink a special beverage before tests that use contrast. CT contrast helps parts inside the body show up clearly in scans. 

Always follow the advice from your child's care team on fasting.

What your child should do

Below are some general guidelines for fasting. These apply to children who can eat or drink by mouth or who are fed using a nasogastric (NG), nasojejunal (NJ), or gastrostomy (G) tube.

NPO: Fasting guidelines for anesthesia or IV sedation
When you arrive at the hospital for your child's appointment: STOP giving your child clear liquids* and CT contrast
3 hours before procedure: STOP giving your child breast milk
6 hours before procedure: STOP giving your child infant formula, Ensure® Clear, or milk (non-human).
8 hours before procedure: STOP giving your child solid food, enteral feeds, Ensure, or liquids not listed as approved clear liquids*.

* Approved clear liquids include:

  • Water
  • Fruit juice with no pulp
  • Carbonated drinks with no particles
  • Coffee and tea with no milk or creamer
  • Sports drinks (such as Gatorade®)
  • Gelatin, such as Jell-O® (non-red)
  • Pedialyte®
  • Ensure® Pre-Surgery
  • Frozen ice pops (not fruit bars)

Please note that Ensure® Clear and similar products are not approved clear liquids.

An exception: PET scans

Your child must not drink anything but water or sugar-free flavored water with contrast medium for at least 4 hours before a PET scan injection. The glucose in other drinks can interfere with the test.

Medicines by mouth

On the morning of anesthesia, give your child all medicines they would normally take unless your child’s care team tells you not to give them. Bring all home medicines with you on the day of anesthesia or sedation.

Usually, taking medicine with a sip of an approved clear liquid will not delay sedation. Medicines taken with any other liquid or solid food, such as yogurt or applesauce, will delay sedation or anesthesia.

For more information

Your child’s care team knows it is hard to keep children from eating when they are hungry. Fasting guidelines are in place to keep your child safe from harm. It is important to follow them.

If you have questions about fasting, talk to your child’s doctor or nurse.

Key points about fasting guidelines

  • Sometimes, your child must go without food or drink before anesthesia or sedation. This is called fasting.
  • Fasting guidelines are in place to keep your child safe. It is important to follow them.
  • Ask your child’s care team if you’re not sure what your child can eat or drink before sedation.


Reviewed: October 2022