CMPA and Milk Allergies in Babies: FAQ, Symptoms and Causes

written by Taylor Cossairt, medically checked by a child nutritionist

For most of us, milk (dairy) is a part of our everyday lives. It’s in your breakfast cereal. It’s in your baked goods. It’s in the cheese on top of your favorite burger. And it’s even a big part of what your baby eats during their first few years.

It’s no surprise then that plenty of new parents worry about their baby developing a milk allergy. But before we jump into the details, here are some quick facts to get started:

  • About 3% of babies have a milk allergy
  • Most children outgrow their milk allergy by the time they’re five years old
  • A milk allergy is your baby’s reaction to proteins found in milk
  • Babies usually show symptoms within a few days or weeks of ingesting cows’ milk formula
  • Cows’ milk is an ingredient in most baby formulas
  • Breastfed babies have a lower risk of milk allergy compared to formula-fed babies
  • Milk allergies are more common in babies than peanut allergies

Now that you’ve got some background info, it’s time to learn even more about milk allergies in babies.

Milk Allergy Symptoms in Babies

True milk allergies are a result of an immune system response inside your baby’s body. Their body doesn’t see milk as something nutritious — they see it as an intruder or an invader.

Your baby’s immune system sends antibodies on a mission to get rid of the intruder. And as those antibodies fight off milk proteins, physical symptoms start showing up. Most milk allergy symptoms in babies manifest in a couple of hours. Here’s a list of the most common milk allergy signs and symptoms to look out for:

Mild milk allergy

  • Runny nose or congestion
  • Coughing and sneezing
  • Dry, itchy, or red skin

Moderate milk allergy

  • Hives, rashes, or raised red bumps along the skin
  • Vomiting or reflux
  • Colic
  • Diarrhea
  • Green, watery, frothy, or loose stools
  • Constipation
  • Refusing to eat/feed

Severe milk allergy

  • Blood in the stool
  • Challenged breathing
  • Shortness of breath
  • Wheezing
  • Anaphylaxis (rare)

Many parents also notice excessive fussiness, sleeplessness, or colic. If your baby cries several hours a day, several days a week, it could be a sign they’re experiencing pain related to CMPA.

How milk allergies present in babies

  • Digestive Symptoms - 60% of infants with milk allergies.
  • Skin Symptoms - 70% of infants with milk allergies
  • Respiratory Symptoms - 30% of infants with milk allergies

Cows’ Milk Allergy in Babies (CMA/CMPA)

When people talk about milk allergies, they usually mean cows' milk allergies. This is an allergic reaction to the proteins found in cow’s milk. And you’ll notice it has a few different acronyms:

  • Cows’ milk allergy (CMA)
  • Cows’ milk protein allergy (CMPA)

It’s the most common type of food allergy in babies, impacting up to 3% of all infants in the UK. It usually shows up when you introduce your baby to formulas or solid foods. And cows’ milk proteins can also pass through a mother’s breast milk to her baby. A common CMPA treatment for babies is avoiding milk and dairy products completely.

There are two types of CMPA:

  • Immediate CMPA - Your baby shows symptoms within minutes of ingesting cows’ milk
  • Skin Symptoms - Your baby shows symptoms several hours or even days after ingestion

When to Call 911 for a Milk Allergy

Although it’s rare, some milk allergy reactions can be life-threatening. If you notice your baby has any of these symptoms, immediately call 911 and seek emergency care.

  • Shortness of breath or challenged breathing
  • Stopped breathing
  • Severe swelling of the mouth, throat, or face
  • Severe cramping and abdominal pain
  • Fast pulse and/or low blood pressure
  • Loss of consciousness

Such clusters of symptoms make up a condition called anaphylaxis. It’s a sudden and extreme allergic reaction that requires immediate medical attention.

While you and your baby wait for emergency medical attention, there are a few things you can do:

  • Administer an epinephrine injection (also known as an EpiPen® or auto-injector)
  • Give your child over-the-counter (OTC) antihistamines if they’re of age

Keep in mind that even if your baby’s symptoms dissipate, it’s possible that another wave of symptoms occurs. Always seek emergency care if your child has a severe allergic response. This is best even if symptoms seem to go away after a few minutes.

Top Foods to Avoid if your Baby has a Milk Allergy

If your baby has a milk allergy, the best way to manage it is by limiting dairy consumption. When you control your child’s exposure to dairy, you also control their risk of reaction. Here’s a list of foods to avoid when your child starts eating solid foods.


Not OK

  • Any kind of milk (evaporated, low-fat, whole milk, and so on)
  • Yogurt-based drinks
  • Milkshakes or malts


  • Soy-based or plant-based formulas
  • Water
  • Fruit drinks





Fruits, vegetables, and starches

Meats and other animal products

Sweets and desserts

Everything listed in the table above is a rough guideline. Not all foods listed above are appropriate for babies, but they might be for older children. Always check with a medical professional about what’s right for your baby’s diet or your child’s age. And don’t forget to check food labels for dairy and milk ingredients like:

Contains Milk

  • Butter
  • Casein
  • Caseinates
  • Cheese
  • Cream
  • Curds
  • Custard
  • Dairy product solids
  • Galactose
  • Ghee
  • Hydrolysates
  • Ice cream
  • Lactalbumin
  • Lactate solids
  • Lactic acid yeast
  • Lactitol monohydrate
  • Lactoglobulin
  • Lactose
  • Lactulose
  • Milk
  • Milk fat
  • Nisin preparation
  • Nougat
  • Pudding
  • Quark
  • Rennet
  • Sherbet
  • Sour cream
  • Whey
  • Whipped cream
  • Yogurt

May Contain Milk

  • Artificial flavoring
  • Natural flavoring
  • Caramel flavoring
  • Flavoring
  • High protein flour
  • Lactic acid
  • “Non-dairy” products
  • Rice cheese
  • Soy cheese

How to Prevent and Treat Milk Allergies in Babies

Milk allergies aren’t curable, but they can sometimes go away on their own with age. In the meantime, work with your baby’s doctor or allergist to develop a treatment plan. Some common milk allergy prevention techniques include:

Allergy action plans
  • Allergy action plans outline your child’s symptoms and what to do in case of an emergency. For example, call 911 and administer an epinephrine injection
  • They’re usually reviewed and signed by your baby’s doctor
  • Give a copy to other caretakers, family members, teachers, and so on
  • Some over-the-counter (OTC) and prescription medications can manage your child’s symptoms
  • OTC antihistamines
  • Prescription auto-injectors
Food label monitoring
  • Check food labels for butter, casein, hydrolysates, and lactoglobulin. Find the full list here
  • Avoid cross-contaminated commercial foods by checking for “may contain milk”
  • Most commercial food labels in the EU and UK state whether they contain common allergens
  • Check labels for bold, underlined, or highlighted text to quickly find allergenic ingredients
Breastfeeding vs. formula-feeding
  • If you breastfeed a baby who has a milk allergy, you may pass along cows’ milk proteins to them
  • If you formula-feed a baby who has a milk allergy, invest in dairy-free formulas.

Milk Allergy vs Lactose Intolerance

Milk allergy and intolerance symptoms look a lot alike, so it’s hard to tell the difference. If your child has a true milk allergy, their immune system attacks the proteins found in cows’ milk. But if they have an intolerance, their body lacks an enzyme that breaks down lactose.

Here are the symptoms of each. Even though they’re similar, notice intolerances usually impact just the digestive tract.

Milk allergy symptoms (immune system)

  • Hives or other skin rashes
  • Vomiting
  • Swelling of the mouth, face, or eyes
  • Wheezing or difficulty breathing
  • Fussiness, sleeplessness, or excessive crying
  • Green, watery, frothy, or loose stools
  • Common in babies and young children
  • Usually goes away with age

Lactose intolerance symptoms (digestive system)

  • Bloating
  • Gas
  • Stomach aches
  • Liquid, green, and/or frothy stools
  • Rare in babies and young children
  • Usually develops with age

The best way to know whether your child has an allergy or intolerance is to visit a medical professional. Doctors and allergists have the tools necessary to diagnose and treat your baby.

How to Diagnose Milk Allergies in Babies

If you suspect your baby has a milk allergy, talk with your doctor right away. They’ll work with you to examine your baby, check their diet, and analyze their symptoms. It’s likely your doctor will order some tests and/or refer you to an allergist for a:

Skin test

Blood test

Stool test

Elimination diet

Explore Other Most Common Foods Causing Allergies in Babies

FAQ: Everything you need to Know about Milk Allergy in Babies

Can babies eat other dairy products if they’re allergic to milk?

Babies with milk allergies can’t eat products made with cows’ milk. This includes dairy products like:

  • Butter
  • Cheese
  • Custard
  • Ice cream
  • Nougat
  • Pudding
  • Sour cream
  • Yogurt

Here’s a full list of ingredients to check for on food labels to make sure your baby doesn’t eat any dairy products.

Do babies outgrow milk allergies?

Is CMPA genetic?

Can infants outgrow cows’ milk allergies?

Should I avoid milk if I’m breastfeeding? What about formula feeding?

How can parents balance a dairy-free diet when breastfeeding a baby with CMPA?

What does a cows’ milk allergy look like in babies?

What does the baby poop look like if they have a milk allergy?