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10 Milk Allergy Symptoms In Babies

Before we talk about milk allergy symptoms in babies,  let’s talk about what exactly a baby milk allergy is.

A milk allergy is a baby’s overreaction to the proteins found in cow’s milk. It is often called MPI (Milk Protein Intolerance) or MSPI (Milk and Soy Protein Intolerance).

It is not lactose intolerance and most (but not all) children outgrow it.

I’ve talked before on my blog about my experience with both of my children, who both had a milk allergy. I was breastfeeding which means that I had to completely eliminate any and all cow’s milk and soy proteins from my diet.

Related: MSPI For Beginners

If you’re here, you probably have a baby who is extra fussy. What’s difficult is that babies ARE fussy. It’s their only way to communicate with us!

The difficulty is determining whether our baby’s fussiness is normal or if it is caused by something that can be changed or prevented.

I wrote a whole post on various causes of baby fussiness. I highly recommend that you go and read it, and then read this post too.

This post contains affiliate links. 

Because unfortunately, a milk allergy can be difficult to diagnose unless your baby has one of the really obvious signs of milk intolerance or milk protein allergy symptoms.

It is said that only 2-3 percent of babies have true baby food allergy symptoms.

However, I know a LOT of moms personally who have eliminated dairy from their diets. I did it for both of my babies.

I believe that it may be more common than the medical community believes.

Whatever it may be, I hope that this resource helps you to determine whether or not your baby’s issues are caused by dairy.

Signs of milk allergy in baby

10 of the most common milk allergy symptoms in babies.

There are many symptoms of milk allergy in infants, and the time frame for when these symptoms appear will vary. For a formula fed baby, adverse reactions can happen within minutes. Signs of a milk allergy in a breastfed baby will likely show up 4-24 hours after exposure. However, if the breastfeeding mom consumes dairy frequently, the symptoms will likely be ongoing.

MSPI symptoms/Milk Allergy Symptoms

Skin Issues

Your baby may have a more severe case of eczema, dry skin, diaper rash, rashes, hives and/or swelling.

Intestinal Issues

Your baby may have reflux, which is often associated with a milk allergy. While all babies have some form of reflux, a more severe type of reflux includes frequent spitting up, forceful vomiting, choking and/or gagging, arching during a feed, discomfort after a feed and difficulty gaining weight.

Your baby might also be excessively gassy, might have green, mucousy stools and/or blood in stool.

Blood in stool is the biggest indicator of a milk allergy, but there are other causes. Read more about reasons for blood in baby stool..

Your baby may also have either diarrhea or constipation.

Breathing Problems

The MSPI baby might have frequent cold symptoms, a persistent cough, frequent ear infections, wheezing or asthma.

Difficulty Gaining Weight

Because your baby is not digesting breast milk or formula properly, and because the mere act of eating causes pain, your baby might be slow to gain weight or might have difficulty gaining weight.

Colicky Behavior

Colic is essentially a term that doctors label babies with when the cause for severe crying is undetermined. In some cases, the cause for this colicky behavior could be a milk allergy.

Treatment For Milk Allergy In Babies

If breastfeeding, you will need to completely eliminate all forms of dairy and hidden dairy (casein, whey, etc) from your diet. You may also need to eliminate soy proteins from your diet as well, as up to 50% of babies that are intolerant to milk proteins are also intolerant to soy proteins.

My Guide To Nursing A Baby With MSPI can help you make this big change easily.

If you are breastfeeding long term, it is possible that you will be able to reintroduce dairy into your diet before weaning.

If your baby is formula fed, there are two options. The first is a hydrolyzed formula (such as Nutramigen or Alimentum) which includes cow’s milk proteins, but in a much more broken down form, making it easier to tolerate. Babies who are unable to tolerate hydrolyzed formulas have to be given an amino-acid based formula (such as Neocate, PurAmino or Elecare).

When Do Babies Outgrow Milk Protein Allergy

Most experts will suggest waiting until milk has been completely avoided for at least 6 months before trying to reintroduce it.

Most babies will outgrow a milk protein sensitivity between the ages of 6-18 months.

Learn about the symptoms that could indicate that your baby has a milk protein allergy.

signs of dairy sensitivity in baby - bestdatatoday

Sunday 30th of October 2022

[…] 10 Milk Allergy Symptoms In Babies – Paper Heart Family […]

Breastfeeding Diet Plans For Weight Loss, Gassy Babies, Colic And Milk Supply - |Huffcare

Friday 25th of December 2020

[…] might also want to check out the symptoms of MSPI in babies. Both of my babies were intolerant to any trace of milk or soy found in my breast milk, and cutting […]


Tuesday 25th of August 2020

You said your babies outgrew the intolerance around 9 months. How do you know? How long after cutting it out did you reintroduce dairy to see if it still affected them? I have been dairy free for 17 days. I've read it takes about a month to clear both mom and babies system. So I'm thinking of reintroducing dairy about 6-8 weeks. But I'm sooo nervous if it doesn't work and my baby is in pain again.


Thursday 30th of September 2021

When I reintroduced, my babies didn't have any more blood in stool, mucus, fussiness, etc.


Thursday 23rd of April 2020

Hi, thank you for writing this! My 2nd daughter has been so much more fussy than my first, and truth be told for a while I found it hard to enjoy her because I feared her awake time. My 1st daughter had eczema all over when she started on cows milk at 12 months. Recently DD2 broke out in red spots over her face and mainly round her chin. I had been having a good helping of greek yoghurt each morning and that's when I started to put 2 and 2 together. After my coffee I'm going to ditch the dairy and see if there are any changes. Would be good to know a time frame of when I should hope to see a difference...? Thanks


Friday 12th of June 2020

I depends on your baby's severity. I would suggest cutting ALL dairy (even hidden!). I had to stay on this diet for 9 months with both of my babies. By that time, they had outgrown the intolerance.

Dairy And Soy Free Dinner Recipes For Nursing Moms -

Monday 12th of November 2018

[…] time to spend looking up recipes on my phone while holding my baby, but I spent that time googling milk allergy symptoms in babies […]