Giving baby formula after it has been prepared can be dangerous for infants. Baby formula is perishable and can spoil quickly if left out. Bacteria multiply rapidly in prepared formula, potentially causing severe illness in babies. To prevent harmful contamination, it is essential to follow proper formula handling and storage guidelines.
Can you give baby formula after 1 hour?
According to the Centers for Disease Control and Prevention (CDC), prepared baby formula should not sit out for longer than 1 hour before being consumed or discarded. After 1 hour, any leftover formula should be thrown away. Fresh formula should then be prepared for the next feeding.
Prepared formula can provide an ideal environment for bacteria like Salmonella, E. coli, and Cronobacter to multiply. When contaminated formula is ingested, it can lead to dangerous infections in babies. Salmonella specifically is a common culprit in outbreaks of illness from spoiled infant formula.
Giving your baby formula that has been sitting out too long puts them at risk of getting sick. Sticking to the 1 hour rule helps limit bacterial overgrowth in prepared formula.
Dangers of giving old formula
There are several risks associated with giving your baby formula that has been prepared more than 1 hour ago:
- Bacterial contamination – Bacteria multiply quickly in formula left at room temperature. Old formula may contain high levels of harmful bacteria.
- Food poisoning – Spoiled formula can cause food poisoning symptoms like vomiting, diarrhea, fever, and abdominal cramps.
- Severe infections – Contaminated formula may lead to dangerous infections in infants such as meningitis, sepsis, or pneumonia.
- Cronobacter infection – This rare but serious infection is associated with ingesting contaminated powdered infant formula.
- Toxic byproducts – Chemical changes in old formula can produce toxins that are dangerous for babies.
The young age and underdeveloped immune systems of infants make them especially vulnerable to illness from spoiled formula. Preparing only what your baby will consume right away reduces the safety risks.
Signs of spoiled formula
Look for the following signs that prepared baby formula has spoiled and should be discarded:
- More than 1 hour since preparation
- Sour odor
- Curdled appearance
- Mold visible
- Discoloration
- Change in consistency
- Formula was left out at room temperature
Trust your senses – if formula smells, looks, or tastes bad, do not feed it to your infant. When in doubt, it is better to be safe and make a fresh bottle.
Proper formula handling
To avoid the risks of bacterial contamination, follow these CDC guidelines for safe formula preparation and storage:
- Carefully sanitize preparation areas and wash hands before making formula.
- Only make enough formula for one feeding at a time.
- Immediately cool formula to fridge temperature after preparation.
- Use prepared formula within 1 hour of making it.
- Discard any leftovers instead of putting back in the fridge.
- When reheating refrigerated formula, heat it up quickly and use immediately.
- Do not save prepared formula to use for another feeding.
Bottles of formula can be kept in the fridge for up to 24 hours. Any formula not drunk 1 hour after being warmed up should be discarded. Following these safe practices reduces the risk of bacteria accumulating in formula fed to babies.
Can you reuse baby formula?
Once baby formula is prepared, it should not be reused or saved for later. The CDC and FDA recommend throwing away any formula left in the bottle after a feeding. Leftover prepared formula should not be put back into the fridge for use at the next feeding time.
Even when properly refrigerated, prepared formula should not sit for longer than 24 hours due to safety and nutritional concerns. As formula is exposed to air and comes into contact with saliva during feedings, bacterial growth is promoted. Nutrients also start to break down over time.
To avoid increased contamination risks, any formula remaining after your baby eats should be discarded. Fresh formula should then be prepared for the next feeding. Reusing old prepared formula can compromise your baby’s health.
Can you reuse nursery water for formula?
The water used to mix with powdered baby formula should not be reused or saved for later. Only fresh water should be used to prepare each batch of formula for your infant.
Like prepared formula, leftover nursery water promotes bacterial growth over time. Standing water provides ideal conditions for bacterial overgrowth. Over just a few hours, bacteria levels can multiply to dangerous amounts.
Reusing old nursery water to make new bottles of formula exposes your baby to spoilage organisms. Even when refrigerated, nursery water should not be held for reuse. Follow the same guidelines for water as prepared formula – use fresh water for each feeding.
Can you mix formula in advance?
Preparing batches of baby formula in advance is not recommended. This allows too much time for bacteria to multiply to unsafe levels before being fed to your infant.
The key is to limit how long formula sits between preparation and consumption. Mixing formula in advance goes against this goal. The FDA states prepared formula should be used within 1 hour to limit bacterial growth.
Batch mixing formula ahead of time also makes it hard to gauge how long it has been held at unsafe temperatures. Even if refrigerated, pre-mixed formula shouldn’t be kept longer than 24 hours.
For safety, it is best to make each baby formula bottle fresh shortly before feeding. Follow the “one bottle, one feeding” rule to avoid bacterial contamination issues.
Can you freeze baby formula?
Prepared liquid baby formula should never be frozen for later use. The CDC cautions against freezing pre-made formula because it can lead to contamination and alter the formula’s nutritional profile.
Freezing prepared formula allows bacteria present to remain dormant until thawed for feeding. The formula can also separate and concentrate, making nutrition content inconsistent.
Powdered formula can safely be frozen for up to 3 months. But liquid concentrate or ready-to-feed formula should not be frozen once opened. Store prepared formula safely in the fridge no more than 24 hours.
Reheating refrigerated baby formula
When properly stored in the fridge, prepared baby formula may be used up to 24 hours after it is made. When ready to use refrigerated formula, it must be quickly warmed to feeding temperature.
The FDA recommends heating refrigerated formula by:
- Holding the bottle under warm running water.
- Placing it in a bowl of warm water for a few minutes.
- Using a bottle warmer.
Microwaves should not be used because they can create hot spots that burn your baby. Stovetops and ovens are also unsafe for warming bottles.
Only heat the formula until lukewarm, not hot. Test the temperature before feeding to your baby. Once warmed up, use the formula right away. Discard any formula not consumed within 1 hour of heating.
How long can formula sit at room temperature?
Both the preparation guidelines and storage times are shorter for baby formula left at room temperature compared to refrigerated. The CDC says prepared formula should not sit at room temperature longer than:
- 1 hour to be used after preparation.
- Up to 2 hours before being discarded.
Bacteria grow much more rapidly at room temperature. Formula kept at room temperature for more than 2 hours after preparation should be thrown out.
Avoid leaving prepared bottles out for feeding or taking them with you when out and about. Refrigerate until ready to warm and use. Discard any formula not used within 1 hour of warming.
Emergency scenario exceptions
There are limited exceptions where it may be necessary to feed your baby formula that has been prepared over an hour ago. Emergency scenarios like natural disasters or power outages can affect ability to safely prepare formula.
In these rare cases, the American Academy of Pediatrics states prepared formula can be used up to 4 hours past the 1 hour safety window. Every effort should still be made to follow safe preparation and storage guidelines.
For non-emergency situations, sticking to the 1 hour timeframe after preparation is strongly advised. Be sure to discard any formula not consumed after baby is done eating.
Can old formula make your baby sick?
Giving your baby formula that is past the recommended 1 hour safety window can definitely make them sick. Consuming contaminated, spoiled formula puts infants at risk of infections and food poisoning.
Prepared formula left out too long provides an ideal environment for dangerous bacteria like Salmonella, E. coli, and Cronobacter to rapidly multiply to unsafe levels. Introducing large amounts of these harmful germs into an infant’s body can have serious consequences.
Possible illnesses from ingesting contaminated formula include:
- Salmonella
- E. coli infection
- Cronobacter sepsis
- Meningitis
- Diarrhea
- Vomiting
- Fever
- Abdominal pain
Given the risk of severe infections in infants, it is critical to discard formula left sitting out too long. Following safe preparation and storage practices helps keep baby healthy.
What to do if baby drinks spoiled formula?
If your baby ends up ingesting formula that may be spoiled, watch closely for any signs of illness and call your pediatrician right away. Symptoms may appear within 1 to 7 days after drinking the contaminated formula.
Seek medical care immediately if your baby has:
- Diarrhea
- Vomiting
- Fever over 100.4°F (38°C)
- Blood or mucus in stool
- Crying or showing signs of abdominal pain
- Unusual drowsiness
- Poor feeding
Your pediatrician can check for dehydration and signs of infection. Prompt medical treatment for vomiting, diarrhea, and fever can help prevent serious complications.
Going forward, be especially diligent about proper formula handling. Discard any leftover formula instead of putting back in the fridge. When in doubt, throw it out and start over with fresh ingredients.
Key takeaways
- Prepared baby formula should only sit out for 1 hour maximum after being made.
- Bacteria multiply quickly in formula left out over an hour, which can make a baby sick.
- Discard any unused portion instead of putting back in the fridge or reusing later.
- When reheating refrigerated formula, warm it quickly and use within 1 hour.
- Never freeze prepared ready-to-drink liquid formula.
- Storing an opened can of concentrate or powder isn’t a safety issue.
- Exercise caution with formula handling to keep your baby healthy.
The bottom line
Letting prepared baby formula sit out for more than 1 hour can be dangerous due to the risk of bacterial contamination. Formula not consumed within 1 hour of preparation should be thrown out. To prevent illness, be diligent about following safe formula handling guidelines from the CDC and FDA.
