Cow Milk Allergy Signs, Symptoms and Diagnosis


Causes, Symptoms, Diagnosis, Management, Advocacy Groups


​Cow milk, a childhood staple and a key source of vital nutrients, is also responsible for the most common food allergy in early life. Learn more about the symptoms that a milk allergy may cause and how Neocate can help.

Cindy, 4 years
Who is Affected By It?

What are food allergies?

Before we dive into details, let's review what is a food allergy. Food allergies occur when the body’s immune system identifies a food as a harmful substance. When the body recognizes anything harmful it will produce antibodies, which are like small soldiers that protect our body’s health. When the body produces antibodies directed against a certain type of food, it causes an immune response. This then releases histamine and other chemicals that trigger allergic symptoms. 

Generally, it is the protein in foods that cause an allergic reaction. Food allergy symptoms may occur right after consuming the allergen or even hours later. These symptoms may affect the respiratory system, gastrointestinal tract, cardiovascular system or the skin.

What is a severe food allergy?

In cases of severe allergic reactions there may be a drop in blood pressure or loss of consciousness. Some people have food allergies so severe that they are at risk for life threatening reactions known as anaphylaxis. Anaphylaxis is a rapid series of serious allergic reactions that affect a number of different areas of the body at once. 

Who is Affected by Cow Milk Allergy?

Cow milk allergy is the most common food allergy in infancy and in the first few years of life. About 2-3 of every 100 infants in the United States is diagnosed with a cow milk allergy. Cow milk allergy typically begins in early childhood and is less common in older children and adults.

Cow milk allergy that starts in infancy can last into childhood, persisting even into early teenage years. Approximately 1 million infants and children under 18 in the US have a cow milk allergy.


Like many allergic disorders, doctors aren’t sure of the exact cause of cow milk allergy, or why some infants develop a milk allergy while others do not. Researchers are working to better understand factors that may contribute to cow milk allergy.

Once a child is diagnosed with a cow milk allergy, the cause of the symptoms is simple: exposure to cow milk proteins!


The immune system of someone with a cow milk allergy will respond to milk as a dangerous invader, leading to signs and symptoms that may be immediate or may take several hours or even several days to appear. Cow milk allergies may cause a range of signs and symptoms, including:

  • eczema, or atopic dermatitis, a skin rash
  • gastroesophageal reflux (GER), spitting up, or vomiting
  • constipation
  • diarrhea
  • fussiness/irritability or "colic"
  • blood and/or mucus in the stool
  • growth failure, or failure to thrive
  • wheezing, or in rare cases anaphylaxis
  • feeding problems
  • nausea

Signs and symptoms of cow milk allergy vary and often resemble symptoms of other illnesses or conditions. A child with a cow milk allergy may have one or several of these signs and symptoms. Your child's doctor can help determine if what you're seeing is related to a cow milk allergy.


For an accurate allergy diagnosis, refer to your healthcare professional. Here are some tests that your healthcare professional may use to help them diagnose a cow milk allergy:

  • Trial food elimination: Suspected foods are removed from the diet to see if signs and symptoms of food allergy improve or resolve. For infants, this can mean continuing to breastfeed while mom avoids suspected food(s) from her diet, or a change in formula.
  • Oral food challenge: Some of the suspected allergen is fed to the patient, often in the doctor's office for safety, to see if a reaction occurs. A food challenge is "open" if the parent and/or patient know what the food is, or "blinded" if they don't know whether it's a safe food or the suspected allergen.
  • Blood tests: Some tests use a patient's blood to see if a food is likely to cause an allergic reaction.
  • Skin prick test: The skin is pricked to introduce a small amount of the potential antigen under the skin (in close contact with the immune system).

For infants suspected of having cow milk allergy, the trial food elimination is used most often by healthcare professionals. It may be followed by an oral food challenge to confirm that there is a food allergy.


There is currently no cure for a cow milk allergy. As with any food allergy, the surest way to manage a cow milk allergy is to avoid cow milk and any foods that contain dairy proteins.

For infants, the first choice may be to continue breastfeeding while mom avoids milk and dairy in her diet, under medical supervision. (She may need to supplement her diet with some nutrients that dairy foods are high in, like calcium.) If formula is needed to supplement or replace breast milk, a hypoallergenic formula is needed.

How Neocate can Help?

Neocate has neither whole nor fragmented protein chains that can trigger an allergic response. Amino acid-based formulas, such as Neocate, are the most hypoallergenic formulas available.

Learn More

The following indicators may be reasons - alone or in combination - that a healthcare team would choose to recommend Neocate to manage a cow milk allergy:

  1. Symptoms not resolved on an eHF
  2. Severe gastrointestinal symptoms
  3. Growth failure, or failure to thrive
  4. Severe eczema, or atopic dermatitis
  5. Multiple food allergies, including cow milk
  6. Symptoms while breastfeeding
  7. History of anaphylaxis to cow milk

Beyond infancy, a substitute for milk is often recommended until at least two years of age if a cow milk allergy has not been outgrown. This helps to ensure that the key nutrients that would usually be provided by cow milk aren't missing from the diet.

Advocacy Groups

Food Allergy Research & Education (FARE) is a nonprofit organization that was formed in 2012 as the result of a merger between the Food Allergy & Anaphylaxis Network (FAAN) and the Food Allergy Initiative (FAI). FARE works on behalf of the 15 million Americans with food allergies, including all those at risk for life-threatening anaphylaxis.

Kids with Food Allergies is a go-to resource as well. They offer daily assistance and practical food allergy management help and have a large online peer support group focused solely on children’s food allergies. Registration is free and a good place for giving and getting help with food ideas, recipes and cooking challenges!

GIKids is a site that provides information for kids and parents on digestive and nutritional disorders, including cow milk allergy. GIKids provides easy to understand information about the management of pediatric digestive conditions such as how they are diagnosed, the treatment and management of conditions, and our patient and parent resources.

Reflux Rebels is a site comprised of the experiences of caregivers who share the common thread of infant reflux and colic. It provides some basic information that has been of help to other families as they advocated for the most effective options for children.

Food Allergy & Anaphylaxis Connection Team (FAACT) is a national non-profit organization who's mission is to educate, advocate, and raise awareness for all individuals and families affected by food allergies and life-threatening anaphylaxis. Whether it’s keeping children safe at school, responding to food allergy bullying, traveling, preparing for college, dealing with workplace issues, or simply taking the family out for dinner, FAACT has all the facts you need to manage food allergies and stay healthy. FAACT is your voice for food allergy awareness.

Cow Milk Allergy Products

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