A woman paying close attention to her child trying to spot the signs of an infant dairy allergy.

How to Spot an Infant Dairy Allergy

Extremely fussy baby? Multiple spit ups after feeds? Noticing some eczema on your baby? If your baby is showing signs of these symptoms, they may be experiencing a dairy allergy. Whether you’re a new mom or a seasoned veteran, seeing your baby in discomfort can be difficult and frustrating. Knowing the signs and symptoms will help you identify or rule out an infant dairy allergy.

In order to understand a dairy allergy, you should first understand lactose intolerance.

Many people, including myself at one point, assume that these two conditions are one and the same. However, they are completely different; different symptoms, different reactions, and different treatments. Lactose intolerance means that your stomach cannot process lactose, the sugar found in milk. The cause of this is the lack of the enzyme lactase in the small intestine. As a result, the body does not process the nutrients from milk, resulting in a negative reaction. The body’s reaction is often more severe than a stomach ache; it can be a series of maladies. When someone is lactose intolerant, the most common symptoms include cramping, bloating, nausea, excessive gas and/or diarrhea. Although lactose intolerance symptoms are uncomfortable and embarrassing, lactose intolerant individuals are in no danger. The difference between lactose intolerance and milk allergies is that milk allergy sufferers have negative physical outward reactions, not just discomfort.

There are many symptoms to look out for when you suspect your child has a dairy allergy.

According to KidsHealth.org, milk allergy symptoms can include loose stools which could contain blood, vomiting, gagging, refusing to eat, irritability or colic, and skin rashes such as eczema. Symptoms may be slow releasing, taking 7-10 days to appear or they could be characterized as “rapid onset,” occurring quickly after exposure. Your child could show one, two, or all of these symptoms. In rare but severe cases, dairy allergy symptoms appear as anaphylaxis. These symptoms include reactions affecting the skin, stomach, breathing and blood pressure. This reaction is not as common in dairy allergy sufferers as it is for peanut and tree nut allergy sufferers, but it is something to watch for. If your child’s symptoms are showing signs of anaphylaxis, seek medical attention immediately.

My son’s dairy allergy was not easily diagnosed.

First of all, my son experienced acid reflux as a baby. While he was steadily gaining weight and rarely displayed irritability (despite excessive spit ups), he struggled with sleeping which concerned me. Doctors reassured me it was just his acid reflux, but I had that mother’s intuition that something else was causing my baby discomfort. I finally asked my doctors do the most common test to diagnose a dairy allergy: a stool test. When the results came back, it was beyond evident that he had blood in his stool, though it wasn’t visible to the naked eye. Thanks goodness for this test – and there are other tests as well! Other tests that could be performed are a blood test or an allergy test. Another form of evaluation is exposure and observation: allowing the child to ingest milk and monitoring their reaction over time. This is also a way to figure out if the child has grown out of the allergy, which often happens around two years old.

So, what do you do if your child has a dairy allergy?

An elimination diet is the solution. When I found out that my son had a dairy allergy, I felt completely overwhelmed. As a nursing mom, this meant I couldn’t ingest dairy in order to avoid exposing him to it. All my favorite foods were off limits and the nutrition label reading was endless. Did you know cereal often contains dairy? I didn’t! Did you know that Oreos do not contain dairy? Me either! I learned so much as I paid attention to nutrition labels. I eventually found out that my son also had a soy allergy, which made my label scrutiny even worse. If you have a child with a dairy allergy who is fed formula, there are many options for you to provide dairy free formula until they are ready to eat solid food. When the time comes for solid food, continue reading those labels. When I had a cross contamination, I knew it. My son’s symptoms would return rapidly – and dairy takes up to two weeks to get out of the system. Always tell restaurants about the allergy, always check labels, and always bring your own food to social gatherings to avoid accidental exposure. If you or your child experiences a cross contamination, simply return to the dairy free diet and monitor the symptoms. They will lessen and go away after the dairy has left the system.

If your child has a dairy allergy, it will be okay.

It can seem overwhelming and it can feel like a ton of work, but doing what is best for your child is worth it. I would always feel guilty if there was an accidental dairy exposure, but one of those moments ended up revealing that my son had grown out of it! Whether your child grows out of it or continues with a dairy allergy, it is a completely doable situation. Stay vigilant and read those labels! 


I think my 9 month old is allergic to dairyy but the doc won’t test her

My LO is so gassy every time she eats – she is EBF. She also has baby acne. Could it be a dairy allergy?

I’ve been dairy free for 10 days because my pediatrician discovered my LO has a dairy protein allergy. His behavior still hasn’t changed though, could it be something else?

My 6 month old has mastered puffs, what could be next? No yogurt drops because she has an allergy

We just switched my 3 month old’s formula to see if his eczema clears up in case it’s a dairy allergy. Now he’s spitting up a lot. Any thoughts?

My 13 month old has a milk allergy and needs to see a pediatric gastroenterologist. Should I be worried?

I recently found out my 3 month old has a milk protein allergy and since I’m nursing I will have to change my diet. Any tips?

What are signs of a dairy allergy for a 3 month old?

Any moms give their baby soy formula? My LO might have a dairy allergy so we are thinking of switching

Has anyone had to cut things out of their diet while breastfeeding? My daughter is 8 weeks old and very gassy and fussy so I’m going to start cutting out dairy first

Get more great advice and meet other moms. Download the SmartMom app today.