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How Long Does It Take For A Baby To Adjust To Formula Change?

Many parents find themselves in the position of needing to change their baby’s formula. You might have to try a few formulas before finding the perfect one, and even then it might take time to know whether it is the right formula. How long does it take for a baby to adjust to a formula change?

It should take a baby around 7 to 10 days to adjust to a new formula. They might show that they like the formula immediately, but it will take a week or slightly longer for improvements to show, or if there are any negative side effects.

If you are changing your baby’s formula, read on to find out what to expect

What Are The Side Effects Of Switching Formula?

If the formula you switch your baby onto is not the right formula for them, there will be some side effects caused by the change.

The negative side effects your baby experiences will depend on how their body reacts to the formula, and if they have any sensitivities or allergies.

Here are some side effects you may notice when changing your baby’s formula:

  • Frequent crying (more than usual)
  • Waking up more frequently
  • Excessive gas
  • Constipation
  • Tensing up
  • Vomiting or spit up
  • Fussiness

These symptoms might be accommodated with an upset stomach, and you will probably notice that your baby is more upset than usual, and grimaces in pain.

This is a sign that they are not taking to the new formula well, and you should speak to your doctor about what to do next.

However, it is important to note that you might see a change in your baby’s stools, but this is not always a bad sign.

The formula might be better for your baby’s digestion, and their new bowel movements are healthier than what they previously were.

This is especially true if you are changing formulas due to the older formula upsetting their stomach.

There is a chance that your baby might show some minor issues with the new formula before it settles with them. These could settle after a few days and your baby could do well with their new formula after this.

How Do I Know If My Baby’s Formula Is Upsetting?

Cute caucasian baby with first baby milk bottle. Top view. Artificial feeding concept. Baby milk formula. Infant in striped jumpsuit on white blanket.

You might notice that the new formula is upsetting your baby straight away, or it might take a few days for the negative side effects to show up.

If you are switching your baby’s formula, you do need to keep a close eye on them for a few weeks to see if their behavior changes, if their sleeping pattern changes, if they seem more upset, or if their bowel movements are different as well.

Noticing any negative changes in your baby the week or two after changing their formula could be a sign that the formula is upsetting them, and it might be worth changing to a different formula.

The safest option is always to speak to your doctor for advice on how to move forward.

Can Switching Formula Hurt My Baby?

Switching formulas can be risky if your baby has a sensitive digestive system or allergies, as it could cause quite a bit of discomfort for your baby.

However, if you do your research and find a formula that you think will work for your baby, and even consult your doctor, this risk is reduced. 

You should avoid switching your baby’s formula unnecessarily, and instead do some good research and consulting before making a change.

If you give your baby the wrong formula, they can battle with stomach pain and congestion, and in more severe cases, allergic reactions.

What Formula Is Closest To Breastmilk?

It does help to choose a formula that is close to breastmilk.

This is often the safest option for babies who do not have special dietary requirements, and babies usually take to these formulas quite easily.

Choosing a formula that is close to breastmilk is ideal for babies who are transitioning from breastmilk to formula, as it is not too big of a change.

Here are two formulas that are closest to breastmilk:

Enfamil Enspire Infant Formula

The Enfamil Enspire Infant Formula is the only baby formula in the USA that contains both ingredients Lactoferrin and MGFM, which makes it as close to breastmilk as formula can be.

Lactoferrin is an essential protein found in breast milk that helps to build the immune system and with intestinal development, with MGFM helping to support mental development.

It is a good quality infant formula that is very similar to breast milk when it comes to nutrients and is one that will definitely benefit your baby.

Gerber Good Start A2 Milk

The Gerber Good Start A2 Milk is an ideal infant formula for babies who need digestive support. It helps to promote gut health and has an exclusive combination of different probiotics and nutrients that make it wonderfully easy to digest.

Free from GMO ingredients, and packed with many nutrients which are naturally found in breastmilk, Gerber Good Start A2 Milk is definitely worth a try.

Is It Normal For Babies To Spit Up After Changing Formula?

It is normal for babies to spit up after changing formula. It might take some time for their digestive system to get used to the new formula, especially if they are sensitive to certain ingredients or have specific allergies.

This should not continue for too long and should subside over a week or two.

This usually is not a problem if they are not displaying any other signs of reacting negatively to the new formula. Just keep an eye out for any other changes.

To help your baby when they are spiting up, try to burp them after feeding to remove any gas that has built up.

This also goes a long way to reduce any discomfort they might be feeling.

Spitting up after formula is more common during the first few months, as their digestive systems are still developing.

This should get better after around 4 to 6 weeks.

How Long Does It Take For A Baby To Adjust To A New Formula

how long does it take for a baby to adjust to formula

How long it takes for a baby to adjust to a new formula does vary from baby to baby.

Generally, it will take about a week or so for your new baby to settle on their formula, and in other cases, it can take up to six weeks.

However, it does not always pay to work on a timeline.

You should take cues from your baby. Watch out for any signs that they are adjusting to the new formula or not.

Some parents even document their baby’s behavior, noting their bowel movements and any new symptoms.

This is a great way to pick up on any changes, to better determine if your baby is improving with the new formula.

If you have had to change your baby’s formula because they were battling with the last one, with symptoms such as constipation, vomiting, or allergies, you should know quite soon whether the new formula is better for them.

If your baby hasn’t improved on the new formula within 3 weeks, it is worth taking them to the doctor. They will better guide you on what you should do going forward, whether to stick it out or change formulas again.

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