Safe Formula Preparation

When preparing a bottle for your infant using powdered infant formula, it is essential to follow a few critical instructions for your child's safety and well-being. Precautions should be taken if your child is younger than 3 months, has a weakened immune system, or was born prematurely; they may be at higher risk of infection from improper feeding methods.

  • Wash your hands thoroughly with soap and water prior to touching any surface or feeding supplies.

  • Ensure the space that will be used to prepare the infant’s bottle is clean and sanitized.

  • Check the expiration date on the formula to be used.

Simple steps to sanitizing the bottle

After washing your hands and sanitizing the space, double-check that the bottle has been cleaned and sanitized to be sure there are no pesky germs left in or on the bottle.

  • Disassemble the bottle, Rinse and clean each part of the bottle with soap and running water. 

  • Sanitize each part of the bottle using your dishwasher on sanitize cycle or a hot water/heated dry cycle OR boil the bottle and parts for 5 minutes. If bottles and their parts are dried completely, let the air dry on a clean towel and surface. 

  • Bottles should be cleaned each time used and sanitized at least once per day.

  • For more information on cleaning infant feeding materials, refer to the CDC’s webpage here.

Proper formula preparation (powdered and concentrate formula):

  • NOTE: Water used should come from a safe source. To find out if your tap water is in the clear, call your local health department. (Directory of local health dept: https://www.naccho.org/membership/lhd-directory)

    • If you do not have safe tap water and bottled water isn’t an accessible option, boil tap water for one minute, and let water cool before adding it to the bottle. 

  • Carefully read the instructions to find out how much formula and water should be added to the bottle being prepared. Remember too much water or too little water can be dangerous for a baby’s health.

  • Always add the correct measurement of water FIRST, and the powdered/ concentrated formula SECOND. (if concentrate, shake prior to measuring and adding to water)

  • Assemble the nipple, ring, and top onto the bottle, and shake well to combine the water and formula together.

Tip: It is not necessary to warm formula, but if you do decide to do so DO NOT MICROWAVE.

  • Run warm water over the prepared bottle OR place the upright bottle in warm water (avoid getting water inside the bottle by keeping the top over the nipple).

  • Test the temperature of the milk by placing a drop of milk on the inside of your wrist. If the water is hot, run it under a bit of cold water and test again.

If using formula to supplement breastmilk, we recommend speaking to an/your IBCLC about how best to do this with your specific experience in mind.

Storage guidance for formula-prepared bottles

  • Use formula bottles within 2 hours of preparation OR 1 hour from start to end of feed.

  • If necessary to prepare bottles in advance, refrigerate immediately after preparation and use within 24 hours.

  • Dispose any unfinished formula bottles.  Do not save or refrigerate. Once a baby's saliva has interacted with the formula, bacteria can grow.

  • Store unused formula in a dry place and check the label for expiration and use by date.

Cronobacter Bacteria 

Cronobacter infection is rare however, it can be deadly to infants.  Infection in infants has been linked to powdered infant formula, so it is recommended to use ready-made or concentrate 

liquid formula in infants that are 2 months or younger, infants born prematurely, and infants with weakened immune systems.  

Follow this PDF from the CDC for more information on how to prevent potential cronobacter infection:  https://www.cdc.gov/cronobacter/pdf/Cronobacter-prevention-infographic-html.pdf