Infant Formula Preparation

Breastfeeding is always recommended as the first choice for feeding your baby. This is sometimes called "exclusive breastfeeding." That is the goal. But sometimes it is not possible. You might have an infection. Or you might be dehydrated (not have enough fluids). Some mothers are taking medicines for cancer or another health problem. These medicines can get into breast milk. Some of the medicines might harm a baby. Also, some babies just need more milk. They may have been tiny at birth. Or they might be having trouble gaining weight. They need extra calories.

Whatever the reason, sometimes formula must be used. Formula comes in different forms:

  • Powder. You mix it with water, as you need it. This is usually the cheapest type of formula.

  • Concentrated liquid. This is also mixed with water, as you need it.

  • Ready-to-eat formula. This comes in a can or bottle. You do not add anything to it.

Make sure you know just how much formula the baby should get at each feeding. Markings on the bottle can help you keep track.


  • Cleanliness is very important. Everything used to prepare a bottle of formula must be as clean as possible. Each time, take these steps:

  • Wash all supplies in warm, soapy water. This includes bottles, nipples, and rings.

  • Boil water. Then put all bottles, nipples, and rings in the boiling water for 5 minutes. Let everything cool before handling it.

  • If you are going to use well water or bottled water to mix the formula, boil it first. This should also be done if you are worried that your water supply is not safe. If you boil water, make sure it boils for at least 1 minute. Then let it cool before using it for the formula.

  • Wash your hands with soap and water.

  • Check the date on the formula container. It is usually on the bottom of a can of formula. This is the expiration date. Check your calendar. Do not use the formula if that date has passed.


Read the directions on the can or bottle of formula you are using. Follow them carefully. This is how formula is usually prepared:

  • For a 4-ounce feeding, using powder:

  • Pour 4 ounces of water into the bottle.

  • Add 2 scoops of formula powder.

  • Cover the bottle with the ring and nipple. Shake it to mix it.

  • Put the plastic top back on the can of formula. Store it in a cool, dry place.

  • When using liquid concentrate:

  • Mix together equal amounts of water and concentrated formula. For a 4-ounce feeding, you would mix 2 ounces of water and 2 ounces of concentrated formula.

  • It is OK to mix more than you need. The extra can be kept in the refrigerator for up to 48 hours. Then, just take it out when it is needed. If any is left after 48 hours, throw it away.

  • When using a ready-to-eat formula:

  • Pour it into the bottle.

  • Any extra can be kept in the refrigerator for 48 hours. If any is left after that, throw it away.

Make sure the formula is the right temperature. If it came from the refrigerator, warm it up. Hold it under warm, running water or place it in a pan of hot water for a few minutes. Never use a microwave to warm up a bottle of formula. Test the temperature by putting a few drops on the inside of your wrist. It should be warm, but not hot.

Use mixed formula quickly. Throw away any formula that has been sitting out at room temperature for more than two hours.