Cow's Milk
Allergy Facts, Symptoms, and Treatment


Across the globe, humans consume milk from a variety of animals (e.g., cows, goats, sheep, water buffalo, and camels) and in a host of ways, such as in liquid form and as part of dairy products including cheese, butter, yogurt, and cream.1,2 Although people in Western countries almost exclusively consume cow's milk, there's a high degree of cross-reactivity between cow's milk and milk from other mammals. So if you react to cow's milk, you may react to milk from any of the aforementioned animals. From a nutritional standpoint, milk is a source of essential nutrients necessary for bone mineralization and growth.3 As such, it's an important food during a child's peak growth periods, and it's the base source for the majority of infant formulas.2,3 Thus, eliminating cow's milk from children's diets without adequate substitutions can lead to nutrient deficiencies and malnutrition.4

However, cow's milk is one of the top eight food allergens in the United States, and in the developed world it's the most common food allergy in infants and children, affecting roughly 2 to 3 percent of children.4,5 The good news is that adult onset milk allergy is rare, and while symptoms in infants usually present within the first six months of life, approximately 80 percent of children outgrow their milk allergies before they turn 16.4,5,6 Therefore, periodic retesting and oral food challenges if indicated are recommended every six to 12 months to track any progress toward outgrowing milk allergy.2

Also note that lactose intolerance and milk allergy are not related. People with a milk allergy have an immune system response and may elicit symptoms such as hives, vomiting, bloody stools, and upset stomach and anaphylaxis. However, those with lactose intolerance can't digest the sugar (i.e., lactose) in milk and may show symptoms such as diarrhea and abdominal gas and cramps.5

Where is cow's milk found?

Cow's milk proteins are found in a host of foods, including unexpected locations such as canned tuna, sausage, and meats (which can contain milk protein), along with beverage mixes, energy drinks, and chewing gum.5 So check all food labels for milk, and maintain a wary eye for the following, which may indicate the presence of milk protein:3,9 artificial butter flavor, butter, butter fat, buttermilk solids, caramel color, caramel flavoring, casein, caseinate, cheese, cream, curds, demineralized whey, de-lactosed whey, flavoring and natural flavoring, fully cream milk powder, galactose, ghee, high protein flavor/flour, lactalbumin, lactalbumin phosphate, lactic acid, lactic acid starter culture, lactosen, rennet casein, rice cheese, solids, sour cream, sour milk solids, whey, whey powder, whey protein, and yogurt.

Additional foods that may contain milk protein include:9 batter-fried foods, biscuits, bread, breakfast cereals, cakes, chocolate, cookies, cream sauces, cream soups, custard, fish in batter, gravies and gravy mixes, ice cream, imitation sour cream, instant mashed potatoes, margarine, muesli, muffins, nonmilk fat, packaged soups, pies, puddings, rusks (biscuits), sausages, sherbet, soy cheese, soup, sweets, and vegetarian cheese.

Plus, myriad "milk" terms can be used on food labels to indicate the presence of milk protein, all of which should be avoided if you're allergic to milk.3 A few examples include:3,9 acidophilus milk, buttermilk, condensed milk, dried milk, dry milk solids, evaporated milk, lactose free milk, malted milk, milk derivate, milk powder, milk protein, milk solid, nonfat milk, pasteurized milk, skim milk, sour milk, and sweetened condensed milk.

Ingesting milk causes the most severe reactions, but both touching and inhaling it can evoke symptoms in some individuals.6 In fact, those highly allergic to milk can react to minute quantities of milk protein and may even elicit symptoms after inhaling milk powder.9

Also note that in the United States and perhaps elsewhere, products labeled as "lactose free," "nondairy," and "kosher" may still contain milk protein.3 Plus, mothers can transmit cow's milk protein via breastfeeding. Thus, those who breastfeed milk allergic infants should refrain from consuming all forms of milk.4

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Are there other allergens I could be sensitized to?*

Some people with cow's milk allergy may also experience symptoms when eating other seemingly unrelated foods. This is called cross-reactivity and occurs when your body's immune system identifies the proteins, or components, in different substances as being structurally similar or biologically related, thus triggering a response. The most common cross-reactivities with cow's milk are milk from other mammals (e.g., goats and sheep) and raw beef.2

Do I need to avoid all forms of cow's milk?

Cow's milk consists of different types of proteins that all have different characteristics that may be associated with varying risk of causing severe allergic reactions. Some people with cow's milk allergy may be able to consume milk if it is extensively heated (baked), as high temperatures break down specific causative proteins.2 In fact, according to a U.S. study, 75 percent of children with an immediate cow's milk allergy (i.e., those whose reactions occur within seconds or minutes of exposure) tolerated baked milk.6 For another patient, milk may need to be avoided in all forms, as it could potentially cause a severe event, also called anaphylaxis. Your specific risk profile depends on which proteins you are allergic to.2

Knowing the proteins, or components, within each allergen that are triggering your symptoms can help guide your management plan. With that in mind, and based on your symptom history, your healthcare provider may suggest something called a specific IgE component test, which can help reveal your risk profile.2

Already have your specific IgE component test results?

Your component test results will include the name of the components (a series of letters and numbers and/or name). Your healthcare provider will likely review the results with you, but here you'll find an at-a-glance breakdown you can use as a reference. Simply match the component names to the list below to see what they mean in terms of symptom management.2

nBos d 4 (alpha-lactalbumin), nBos d 5 (beta-lactoglobulin)

  • Sensitive to heat, extensively heated (i.e., baked) milk may be tolerated.
  • Falling IgE levels over time may indicate that tolerance to milk develops.

nBos d 6

  • Sensitive to heat, may tolerate baked milk in food and extensively heated beef (raw beef may cause symptoms).

nBos d 8

  • Stable to heat, risk for reactions to both fresh and baked milk.
  • High levels of IgE may indicate that allergy is unlikely to be outgrown.
  • Falling IgE levels over time may indicate that tolerance to milk develops.

Test results should be interpreted by your healthcare provider in the context of your clinical history. Final diagnosis and decision on further management is made by your healthcare provider.

*These products may not be approved for clinical use in your country. Please work with your healthcare provider to understand availability.

How do I manage my allergy?

Because there is no cure for food allergies, your healthcare provider may recommend a plan that includes the following.11-14

  • Read ingredient labels and “may contain” advisory panels on food and nonfood products carefully, and avoid all foods and products containing any form of the allergen. Note that these lists and panels may not appear on the same side of a product’s packaging and that manufacturers frequently change ingredients. If you’re unable to obtain a list of ingredients, it’s safest to avoid that item.
  • Avoid cross-contamination when cooking by using two sets of cooking and eating utensils, with one exclusively for the allergic individual. Wash all dishes and utensils in hot soapy water between uses.
  • Craft an action plan with a list of steps for you and others to take should you accidentally ingest the allergen. Print out a copy of the plan and carry it with you.
  • Talk with restaurant chefs about your allergy and order food that’s simply prepared and void of any form of the allergen. Avoid desserts, as they often contain or have come into contact with food allergens.
  • Plan ahead for traveling to ensure your food allergy will be managed and any emergency medication is always available.
  • Wear a medical ID bracelet identifying the allergen to which you're allergic.
  • Carry any recommended or emergency medication with you at all times.
  • Teach children with food allergies which foods to avoid. Work with caregivers and school staff to eliminate or reduce exposure to the allergen and to ensure they understand when and how to use medication to treat symptoms.

Your healthcare provider may direct you to take one of the following medications:

  • Epinephrine auto-injector when there are signs of an acute severe event, aka anaphylaxis (see below). Ensure your family members know how to administer it in case of an emergency.
  • Antihistamines as a supplement may be useful in relieving mild symptoms (e.g., itch); however, they do not halt the progression of an allergic reaction.
  • Bronchodilator (albuterol) as a supplemental therapy for respiratory symptoms, especially in those with a history of bronchospasm or asthma.

If you're with someone who's having an allergic reaction and shows signs of shock, act fast. Look for pale, cool, and clammy skin; a weak, rapid pulse; trouble breathing; confusion; and loss of consciousness. Do the following immediately:

  • Call local emergency services.
  • Ensure the affected individual is lying down with legs elevated.
  • Administer epinephrine immediately for any obvious signs of anaphylaxis.
  • Check the affected individual's pulse and breathing and administer CPR or other first-aid measures if necessary.

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Common Symptoms

Cow's milk allergy can range from mild to severe and may vary over time, resulting in mild symptoms during one episode and severe symptoms in another. Although food allergy symptoms can start a few minutes to several hours after ingestion, most begin within two hours.7 Symptoms may involve the skin, gastrointestinal tract, cardiovascular system, and respiratory tract, and may include one or more of the following:5,7,8

  • Bloody stools (especially in infants)
  • Abdominal pain, diarrhea, nausea, vomiting, stomach cramps
  • Hives (allergic urticaria), itching, eczema
  • Wheezing, nasal congestion, shortness of breath, repetitive cough
  • Shock, circulatory collapse
  • Tight, hoarse throat, trouble swallowing
  • Pale or blue skin coloring
  • Dizziness, lightheadedness, fainting, weak pulse
  • Anaphylaxis, a potentially life-threatening event

How do I know if I'm allergic?*

Together with your symptom history, skin-prick testing or specific IgE blood testing can help determine if you are allergic to a particular allergen. If you are diagnosed with an allergy, your healthcare provider will work with you to create a management plan.

It's important to note that some children with milk allergy may outgrow their allergy, and food can be reintroduced. Therefore, periodic retesting and oral food challenges are recommended to track any progress toward outgrowing milk allergy.10

*These products may not be approved for clinical use in your country. Please work with your healthcare provider to understand availability.

Is there a risk for a severe event?

Because food allergic reactions are unpredictable and symptoms range from local reactions to systemic, it is recommended that an epinephrine prescription be considered for any patient with an IgE-mediated food allergy.11

The majority of reactions to cow's milk allergy are mild to moderate, but in 1 to 2 percent of allergic individuals, anaphylaxis can also occur. In fact, cow's milk is among the most common foods capable of causing anaphylaxis.4

  1. Encyclopedia Britannica [Internet]. Chicago: Encyclopedia Britannica Inc.; 2019 Feb 20. Available from: https://www.britannica.com/topic/milk.
  2. EAACI, et al. Molecular allergology user's guide. Pediatr Allergy Immunol. 2016 May;27 Suppl 23:1-250. doi: 10.1111/pai.12563. PMID: 27288833. (157-166 p.) Available from: http://www.eaaci.org/documents/Molecular_Allergology-web.pdf.
  3. Kids with Food Allergies [Internet]. Arlington, VA: Asthma and Allergy Foundation of America; 2020. Available from: https://www.kidswithfoodallergies.org/milk-allergy.aspx.
  4. Lifschitz C, Szajewska H. Cow's milk allergy: evidence-based diagnosis and management for the practitioner. Eur J Pediatr. 2015 Feb;174(2):141-50. doi: 10.1007/s00431-014-2422-Epub 2014 Sep 26. PMID: 25257836; PMCID: PMC4298661.
  5. American College of Allergy, Asthma & Immunology [Internet]. Arlington Heights, IL: American College of Allergy, Asthma & Immunology; 2019 Mar 21. Available from: https://acaai.org/allergies/types-allergies/food-allergy/types-food-allergy/milk-dairy-allergy.
  6. The Anaphylaxis Campaign [Internet]. Farnborough, UK: The Anaphylaxis Campaign; 2019 May. Available from: https://www.anaphylaxis.org.uk/wp-content/uploads/2019/07/Milk-Allergy-2019.pdf.
  7. American College of Allergy, Asthma & Immunology [Internet]. Arlington Heights, IL: American College of Allergy, Asthma & Immunology; 2014. Available from: https://acaai.org/allergies/types/food-allergy.
  8. Mayo Clinic [Internet]. Rochester, MN: Mayo Foundation for Medical Education and Research; 2019 Nov 2. Available from: https://www.mayoclinic.org/diseases-conditions/food-allergy/symptoms-causes/syc-20355095.
  9. Steinman HA. Hidden allergens in foods. J Allergy Clin Immunol. 1996;98:241-50.
  10. Guidelines for the diagnosis and management of food allergy in the United States: report of the NIAID-sponsored expert panel. J Allergy Clin Immunol 2010 Dec;126(6 Suppl):S1-58.
  11. Wright BL, Walkner M, Vickery BP, Gupta RS. Clinical Management of Food Allergy. Pediatr Clin North Am. 2015 Dec;62(6):1409-24. doi: 10.1016/j.pcl.2015.07.012. Epub 2015 Sep 7. PMID: 26456440; PMCID: PMC4960977.
  12. American College of Allergy, Asthma & Immunology [Internet]. Arlington Heights, IL: American College of Allergy, Asthma & Immunology; 2014. Available from: https://acaai.org/allergies/types-allergies/food-allergy/food-allergy-avoidance.
  13. Harvard Health Publishing [Internet]. Boston, MA: Harvard Medical School; 2020. Available from: https://www.health.harvard.edu/healthbeat/6-tips-for-managing-food-allergies.
  14. Mayo Clinic [Internet]. Rochester, MN: Mayo Foundation for Medical Education and Research; 2019 Sep 14. Available from: https://www.mayoclinic.org/diseases-conditions/anaphylaxis/symptoms-causes/syc-20351468.