When does cow’s milk allergy start?


Kurt Olsen

Cow’s milk allergy is an allergic response to cow’s milk protein. Diagnosis might be challenging since it is mostly reliant on history and physical examination. This activity describes the examination and treatment of cow’s milk allergy, as well as the role of the interprofessional team in the care of patients with this disease.


  • Determine the pathology of cow’s milk allergy.
  • Describe the normal history and physical findings in cow’s milk allergy patients.
  • Describe the various treatment and management options for cow’s milk allergy.
  • Summarize the significance of interprofessional team collaboration in improving the care of children with cow’s milk allergies.

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Cow’s milk allergy is a frequent diagnosis in children and babies. It usually manifests as an allergic response to the protein contained in cow’s milk. Cow’s milk allergy causes a number of symptoms and indications that often appear in babies and may resolve by the age of six. Because of the milk-free diet, it may cause parental and family stress and, if not managed properly, can lead to nutritional deficiencies.


Food allergies are caused by the host’s immune system. If a person is allergic to milk, the immune system reacts to a particular milk protein, initiating an immunological response and attempting to neutralize the triggering protein. When the body comes into touch with the protein again, the immune reaction identifies it. It activates the immune system, causing histamine and other immune mediators to be released. Cow’s milk allergy symptoms are caused by the release of substances.


Due to the absence of a definite criteria for diagnosis, it is impossible to ascertain the actual prevalence of cow’s milk allergy. Allergy is often used interchangeably with intolerance or hypersensitivity. Infants seem to have a prevalence of 2 to 3% in the industrialized world. There is little indication that prevalence is rising, and parents perceive cow’s milk allergy more commonly than an oral challenge can confirm.[2][3] By the age of six, the frequency has dropped to fewer than one percent.


Cow’s milk has about 20 different protein components. Casein protein (alpha-s1-, alpha-s2-, beta-, and kappa-casein) and whey proteins are the most common allergens. (alpha-lactalbumin and beta-lactoglobulin).[5] Most people who are allergic to cow’s milk are sensitive to both caseins and whey proteins. There are two types of immune-mediated adverse food reactions: IgE-mediated and non-IgE-mediated. Cow’s milk allergy is most often caused by a non-IgE mediated pathway.

History and Physical

Cow’s milk allergy normally manifests itself during the first few months of infancy, and usually before the age of six months. Symptoms may appear a few days or weeks after consuming cow’s milk protein. The symptoms might range from diarrhea and emesis to potentially fatal anaphylaxis. In situations involving the GI tract, the kid may get dehydrated and fail to flourish.

Cow’s milk allergy responses are classified as either fast onset, IgE mediated, when symptoms appear within an hour of ingestion, or delayed onset, non-IgE mediated, where symptoms appear hours or days later.[8]

Rapid onset symptoms can include:

  • Urticaria/hives
  • Wheezing
  • Itching or tingling sensations around the mouth or lips
  • Angioedema is defined as swelling of the lips, tongue, or throat.
  • Coughing or shortness of breath
  • Vomiting
  • Anaphylaxis

Slow onset symptoms can include:

  • Diarrhea
  • Hematochezia
  • Abdominal cramps
  • Colic

Anaphylaxis is a medical emergency that requires an epinephrine injection and assessment in the emergency department. The following signs and symptoms may appear immediately after consuming milk:

  • Increased work of breathing
  • Constriction of airways
  • Swollen throat
  • Facial flushing
  • Itching

The doctor must distinguish between milk allergy and milk intolerance. The main distinction is that intolerance is not associated with the immune system. After consuming milk, common signs of milk intolerance include gas, bloating, or diarrhea. Treatment for intolerances and allergies differs.


Cow’s milk allergy cannot be detected with a particular test. The history of symptoms and physical exam are used to make the diagnosis. It is critical to provide a chronology of symptoms and when they arise. A testing approach for suspected cow’s milk allergy in babies may assist to rule out the condition.

If needed, primary tests include a skin prick test and serum-specific IgE. Both tests have a high sensitivity but a poor specificity, and they may be positive in non-allergic people.

Serum-specific IgE to cow’s milk allergy: This may help in the diagnosis of IgE-mediated cow’s milk allergy, and the cut-off values are multifactorial and should be determined by each allergist.

An allergy expert may conduct a skin prick test.

If cow’s milk protein is detected, a newborn should be given a diet devoid of it for a month. If symptoms improve after removing the implicated meal, an oral food challenge is the gold standard test. Because of the risk of systemic IgE-mediated reactivity, this challenge must be performed in a medical environment. Every 6 to 12 months, patients should be evaluated to see whether they have established a tolerance to cow’s milk protein.


1: If there are symptoms of anaphylaxis or an acute response, food exclusion is advised, followed by serum IgE testing. If the serum-specific IgE level is elevated, the kid is diagnosed with a cow’s milk allergy. If IgE levels are low and symptoms improve following a diet change, an oral challenge should be attempted. The diagnosis is verified if the symptoms repeat. If the symptoms do not reappear, a cow’s milk allergy diagnosis is ruled out.

A elimination diet is indicated if the symptoms are not consistent with anaphylaxis or acute response. If the symptoms improve, an oral challenge should be performed, and if the symptoms return, the diagnosis is established. If the symptoms do not reappear, the diagnosis of cow’s milk allergy is ruled out.

3: If symptoms do not improve following the exclusion diet, the diagnosis of cow’s milk allergy is ruled out, and the patient should be evaluated further.

Treatment / Management

The only effective therapy for all food allergies is to completely eliminate the offending item from the diet. If a kid begins a milk-free diet, a doctor or nutritionist may assist in planning nutritionally balanced meals. To replace calcium and minerals contained in milk, such as vitamin D and riboflavin, the parent or kid may need to take supplements.

nursing: Cow’s milk allergy rates in nursing newborns are lower than in formula-fed infants, with an estimated 0.5%. Breastfeeding is advised, especially if the baby is at high risk of developing milk allergy. Cow’s milk proteins are transferred to the kid through breastfeeding and may induce an allergic response. If the kid has a cow’s milk allergy, the mother should avoid any foods containing cow’s milk protein, such as cheese, yogurt, and butter.

Hypoallergenic formulations: Enzymes are used to hydrolyze the milk proteins in these formulas. Products are characterized as partly or extensively hydrolyzed/elemental formulations based on their processing degree. Due to increased allergenicity and related responses in partly hydrolyzed formulas, recommendations are for fully hydrolyzed formulations.

Soy-based formulas: Up to 50% of children with cow’s milk protein intolerance acquire soy protein sensitivity when given soy-based formulas. As a result, soy-based formulas are often not a feasible alternative for treating cow’s milk protein intolerance.

Alternative milk: due to a high degree of cross-reactivity with cow’s milk protein, replacements such as sheep’s and goat’s milk are often not appropriate.However, studies demonstrate that the incidence of cross-reactivity to camel’s milk has reduced.

Acute treatment:

If a youngster accidently swallows milk, despite parental precautions, drugs such as antihistamines may lessen the mild allergic response.

If the parent or kid has a severe allergic response, an emergency epinephrine injection and a trip to the emergency department may be required. If there is a chance of a severe response, the parent or kid should have injectable epinephrine on hand at all times. To be prepared for an emergency, these people should have their doctor or pharmacist show how to use this device.

Differential Diagnosis

Because cow’s milk allergy may produce a broad range of symptoms, the differential diagnosis can be comprehensive, including but not limited to:

  • Other food allergies
  • Celiac disease
  • Enteropathy
  • GI infections
  • Enterocolitis
  • Inflammatory bowel disease
  • Meckel diverticulum
  • Angioedema
  • Lactose intolerance
  • Idiopathic urticaria
  • Anaphylaxis


Cow’s milk protein allergy has a favourable prognosis in infancy and early childhood. Approximately 50% of afflicted children gain tolerance by the age of one year, more than 75% by the age of three years, and more than 90% by the age of six years.

Children who have a milk allergy are more prone to acquire other food allergies. Up to 50% of youngsters have associated adverse responses to diverse meals, and 50% to 80% develop allergies to inhalants before puberty.

Pearls and Other Issues

  • Cow’s milk allergy is a frequent diagnosis in children and babies.
  • Due to the absence of a definite criteria for diagnosis, it is impossible to determine the actual prevalence of cow’s milk allergy.
  • It is divided into two categories: IgE-mediated and non-IgE-mediated.
  • Cow’s milk allergy normally manifests itself during the first few months of infancy, and usually before the age of six months.
  • The doctor must distinguish between milk allergy and milk intolerance.
  • The history of symptoms and physical exam are used to make the diagnosis.
  • The only effective therapy for all food allergies is to completely eliminate the offending item from the diet.

Enhancing Healthcare Team Outcomes

The pediatrician, family physician, and nurse practitioner are the main caregivers for the majority of children with cow’s milk allergies. In most situations, avoiding milk may address the issue; nevertheless, since milk products are so prevalent, the danger of an allergy cannot always be eradicated. Patients with persistent allergies should be referred to a specialist.

An allergist is the best person to identify a cow’s milk allergy, although the primary care physician is generally in charge of long-term treatment and monitoring. The patient and family should be counseled and educated about their medical condition, as well as the significance of avoiding foods containing cow’s milk protein. Primary doctors should teach parents that cow’s milk allergy may be a medical emergency, and if there is a history of fast response or anaphylaxis, epinephrine should be carried at all times.

Cow’s milk allergy needs a multidisciplinary team approach, comprising doctors, specialists (most notably an allergist), specialty-trained nurses, and pharmacists, all working together to obtain best patient outcomes. The pediatric nurse, who informs the rest of the team, may educate the family. Pharmacists may help with formula selection and drug review.

Related Questions

  • Can a milk allergy start at any age?

    Milk allergies may affect people of any age, although they are more frequent in young children. Many children grow out of it, but others do not.

  • Can toddler develop sudden milk allergy?

    Yes. Lactose intolerance may develop in children momentarily after a virus illness (which is why you may be urged to avoid milk with lactose in it during a stomach bug) or it can be observed with disorders that cause gut inflammation, such as celiac disease.

  • What age group is most likely to have a milk allergy?

    Cow’s milk allergy is frequent in newborns and young children, often developing before the age of six months. It affects around one in every fifty babies, but is far less prevalent in older children and adults, since the majority of afflicted individuals will grow out of their allergy.

  • Can a milk allergy start at 3 months?

    Symptoms of cow’s milk allergy
    CMPA symptoms often appear in the first few weeks and months of infancy.


  • https://www.ncbi.nlm.nih.gov/books/NBK542243/#:~:text=Typically%20the%20presence%20of%20cow’s,emesis%20to%20life%2Dthreatening%20anaphylaxis.

Contact Us

For more information or to make comments and suggestions, please contact:
Kurt Olsen
Dairy Development Coordinator, Missouri Department of Agriculture
Phone: (573) 291-5704
E-mail: [email protected]