How to Tell if Baby Formula is Upsetting Stomach

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One of the many challenges of parenthood is figuring out what your infant needs and satisfying these needs. And this is, unfortunately, never an easy task. 

Feeding your little one comes with a lot of challenges, and one of them is deciding on the right baby formula. 

But, even the right formula can cause issues. So, if you want to know how to tell if it’s the baby formula that is upsetting their stomach, you’ve come to the right place.

It’s not as uncommon as you think.

How to Tell If Baby Formula is Upsetting Stomach

Being alert all the time and trying to figure out what’s going on with your little one can be highly stressful. Nevertheless, it’s always essential so you can step in if there’s something wrong with your baby. 

Here are a few symptoms to tell you that the baby formula you’re using is upsetting their stomach or not working for them. 

Vomiting After Feeding

Most infants spit up regularly, especially if not held upright during and after feedings, or the teat allows the milk to flow too fast. However, if your baby is throwing up, it might be allergic to one of the ingredients in the formula, or there might be a problem with preparing or storing it.

It’s important to know if they’re vomiting straight after or after a delay – straight after may mean they’re full, a delay could mean the formula disagrees with their tummies. 

Suffering From Gas

Your baby will suffer from gas if the teat makes the milk flow too fast, pushing your little one to swallow much air with the formula. Gas is also common if you’re not holding the baby properly while feeding or you forget to burp it after feeding is over. 

However, gas can result from a sensitivity or allergy to one of the ingredients in the formula. It might be causing too much constipation, which allows the gas to accumulate and cause discomfort.

Is your baby burping or trumping a lot? A sensitivity to cow’s milk should mean gas AND diarrhea.

Crying At the Beginning or End of Feeding

Crying is expected if the baby is struggling with over or under-feeding. Moreover, your infant will be fussy and show discomfort if it’s allergic to any of the formula’s ingredients.

However, the crying can also be a result of the discomfort afterwards such as gas and colic.

Constant crying, as in, non-stop howling, is a common result of allergies/lactose intolerance to the contents of formula milk.


baby crying from formula

Colic is quite common in newborns, and there are many reasons behind it. However, choosing the wrong formula can also cause colic. Your baby might start crying uncontrollably because of the pain. 

Colic can be a common symptom of formula feeding and not necessarily because that they disagree with the ingredients but the delivery of it – too fast.


After the first month, your infant might pass stool every day or even every other day. However, if you notice that your baby doesn’t pass stool or that the stool is too hard, this might be related to the formula you’re using. 

The protein content in some baby formulas can be the culprit behind constipation. Constipation will also cause gas and make your little one extremely upset. 


The consistency of the stool changes all the time as your little one’s digestive system develops. However, if you notice that the stool is always watery, there might be a problem with the feeding formula you’re using.

Baby poo is often loose, but diarrhea is obvious – it will be water and have a foul(er) smell.

Mucus or Blood in Stool

Seeing a drop of blood in your baby’s diaper can be caused by passing large pieces of stool or having cracked skin in the rectum. However, it can also be due to an allergy to one of the formula’s ingredients. Mucus in stool is also a sign that there’s something wrong with the formula, leading to the excessive production of mucus in the intestines. 

This could also be a sign of infection – has the formula been prepared with boiling water? If you use a perfect prep machine has it been cleaned properly?

Trouble Sleeping

Your baby is supposed to sleep for most of the day, but if you notice that your little one wakes up more often or struggles to stay asleep for a couple of hours after feeding, the feeding formula might upset the baby’s sensitive stomach.

Babies sleep vary and they do tend to wake up often but a baby who isn’t working well with formula will often wake up very uncomfortable and crying – they may appear in pain (they probably are).

Rashes And Skin Conditions

Rashes, hives, and eczema indicate that there’s something going on inside your kid’s stomach. You might also notice a red ring around the rectum if the formula doesn’t work for your little one. 

Allergic reactions on the inside often make their way outside.

What to Do if Baby Formula is Upsetting Stomach

You can do a few things if the baby formula isn’t working for your little one. 

Get Your Baby Tested

If you notice any discomfort or unusual symptoms, ask your doctor. Your doctor will run the necessary allergy tests to identify the ingredient that is making your baby uncomfortable. He or she will also suggest a suitable alternative to relieve discomfort, so your baby can feed comfortably. 

Start Breastfeeding


Relactation is quite common among mothers who notice that their little ones aren’t reacting well to formula feeding. After consulting your doctor, switching to breastfeeding might be the best option for you and your little one. 

Babies are unlikely to be allergic to their own mother’s milk.

In the beginning, you might struggle with offering the breast, but some babies latch on the breastfeed quite easily. Expressing your breasts will help with milk production, which eventually will encourage your infant to feed. However, you might still need another alternative until your breasts are able to make the amount of milk that your infant needs. 

You could even breastfeed and formula feed.

Give a Massage

Giving your little one’s belly a gentle massage is an excellent way to relieve any discomfort and accumulated gas. Massaging the whole body and moving the baby’s legs in a cycling motion will also help release gas and alleviate pain. 

However, if your baby still has gas after every feeding session, then you should try to find another alternative. 

Change Formula

If your little one is allergic to the current formula, you can consider other alternatives. For example, goat milk formulas are safe for your infant from birth, but fresh goat milk isn’t. Any type of fresh milk like goat milk or cow milk should be given to your child after the age of 12 months. 

Coconut and rice milk formulas are also safe for your kid but only after the first birthday. Before introducing any of these alternatives, you need to ask the doctor and see if they’ll work for your baby. 


Choosing and providing your little one with the right baby formula is one of the most challenging decisions that a parent can face. This is why you need to pay attention to any unusual symptoms to see if the formula is upsetting your baby’s stomach. 

There are several alternatives to consider if the current formula isn’t working for your little one. But first, you need to consult the doctor to make sure that this current formula is safe and that your baby isn’t allergic to any of the ingredients.