Choosing a formula
Your family doctor will usually recommend a formula made from cow's milk. Some formulas are iron-fortified (which means they have extra iron in them). Some formulas have very little iron or none at all. Most doctors recommend using an iron-fortified formula. Remember that regular cow's milk is not the same as infant formula made from cow's milk. Some formulas are made of soy milk instead of cow's milk. If your baby seems to be allergic to formula made from cow's milk, your doctor may suggest using a soy-milk formula. Use infant formula for the first year. Babies aren't ready for regular cow's milk until about the time of their first birthday.

Baby formula is sold in several forms:
Ready-to-use This is the most expensive kind of formula, but no mixing is necessary. Concentrated liquid This is a less expensive formula. You mix the formula liquid with an equal part of water. Powder This is the least expensive formula. You mix one level scoop of powdered formula with 2 ounces of water and stir well.

Switching to a different formula
Sometimes it may be necessary to change the kind of formula that your baby drinks. Extreme fussiness, certain food allergies, or a need for more iron are some of the reasons why your baby's formula may need to be changed.If you're concerned about your baby's stool habits or about the color or consistency of the stool, changing his or her formula isn't necessarily the answer. How often babies soil their diapers and the color and consistency of their stool is different from baby to baby. Talk with your doctor before changing your baby's formula--you may not need to change after all.Report any of these symptoms to your doctor:
  • Dry, red and scaly skin
  • Diarrhea
  • Extreme fatigue or weakness
  • Forceful vomiting

Sterilizing and cleaning
You should sterilize bottles and nipples before you use them for the first time. You can do this by putting them in boiling water for 5 minutes. After that first time, you probably don't need to sterilize them again. Instead, wash bottle, nipples and caps in hot, soapy water. Rinse them carefully. You can also run them through the dishwasher, which kills more germs than washing by hand.

Mixing formula
The most important thing to know is that you must follow the directions on the formula container exactly. Always measure carefully and never add extra water to the formula. You should also wash your hands before preparing the formula.If you use well water or there are problems with the water in your town, you may want to boil the water first or use bottled water. If you boil the water, let it cool off before mixing it with the formula. Always use a clean cup to measure the water.

Warming bottles
You can probably feed your baby a bottle without warming it first. It is okay for the formula to be cool or room temperature. If your baby seems to prefer warm formula, you can put the filled bottle in a container of warm water and let it stand for a few minutes. Check the temperature of the formula on your skin before feeding it to your baby, to be sure it isn't too hot. The formula should only be lukewarm.Do not heat bottles in the microwave. Microwaves heat foods and liquids unevenly, and this can cause hot spots in the formula that can burn your baby.


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Written by familydoctor.org editorial staff.
American Academy of Family Physicians