How do I manage a dairy allergy in an infant?

Management of Dairy Allergy in an Infant

For breastfed infants with confirmed cow's milk protein allergy, continue breastfeeding while the mother eliminates all cow's milk and dairy products from her diet; for formula-fed infants, use extensively hydrolyzed formula as first-line treatment, reserving amino acid-based formula for severe reactions or treatment failures. 1, 2

Breastfed Infant Management

Continue Breastfeeding with Maternal Elimination Diet

• The mother should eliminate all cow's milk and dairy products from her diet while continuing to breastfeed, as this preserves the numerous benefits of breastfeeding while addressing the allergic condition. 1, 2, 3

• Cow's milk proteins transfer through breast milk in sufficient quantities to cause allergic reactions in sensitized infants, though not all allergic infants will react to these proteins through breast milk. 4, 2

• Complete elimination includes milk, cheese, yogurt, butter, and hidden sources in processed foods. 1

Timeline and Monitoring

• Symptoms typically improve within 1-2 weeks of maternal elimination, though improvement may take up to 4 weeks depending on the type of allergic manifestation (IgE-mediated reactions resolve faster than non-IgE-mediated conditions like eosinophilic esophagitis). 1, 2, 3

• After 1-2 weeks of elimination, perform a rechallenge by reintroducing dairy to the maternal diet to confirm the diagnosis before implementing longer periods of dietary restriction. 4, 3

• If symptoms do not re-emerge with maternal dairy reintroduction, the diagnosis is not confirmed and the elimination diet should be discontinued. 4

Nutritional Support for the Mother

• Refer the mother to a registered dietitian to ensure nutritional adequacy of the maternal diet while avoiding cow's milk proteins. 1, 2, 3

• Provide calcium supplementation and address other nutritional considerations to maintain maternal health during breastfeeding on a restricted diet. 1, 2

• Avoid unnecessarily restrictive maternal diets beyond cow's milk elimination unless other food allergies are confirmed, as overly restrictive diets may compromise maternal nutrition and breastfeeding ability. 4, 1, 3

Formula-Fed Infant Management

First-Line Treatment

• Use extensively hydrolyzed formula (eHF) as first-line treatment for formula-fed infants with cow's milk allergy, which has an 80-90% success rate. 1, 2, 5

When to Use Amino Acid-Based Formula

• Use amino acid-based formula (AAF) for:

  • Severe reactions or life-threatening symptoms (anaphylaxis) 1, 2, 6
  • Infants who fail to respond to extensively hydrolyzed formula after an appropriate trial 1, 2, 6
  • Acute and chronic severe food protein-induced enterocolitis syndrome 6
  • Cow's milk allergy associated with multiple food allergies 6
  • Eosinophilic esophagitis not responding to an extended exclusion diet 6

• The main benefit of AAF is its complete absence of residual allergenicity, making it the safest option in severe cases. 6

Formulas to Avoid

• Do not use soy formula as a first-line alternative due to 20-40% cross-reactivity risk with cow's milk protein allergy. 1, 2, 3

• Do not use goat's milk or sheep's milk as alternatives due to high protein sequence homology with cow's milk (these proteins are too similar and will trigger the same allergic reaction). 1, 2, 3

When Breastfeeding Should Be Discontinued

• Consider discontinuing breastfeeding and switching to hypoallergenic formula if:
  • Symptoms persist despite strict maternal dietary elimination for 2-4 weeks 1, 2
  • The infant has failure to thrive 3
  • The mother is unable to maintain the elimination diet 1
  • Consultation with an allergy specialist is recommended if symptoms persist despite strict maternal elimination. 1

Introduction of Complementary Foods

• Do not delay introduction of solid foods beyond 4-6 months of age in infants with cow's milk allergy. 4, 2

• Potentially allergenic foods (other than cow's milk) can be introduced at 4-6 months as tolerated. 4

Reintroduction Protocol

• Attempt reintroduction of cow's milk protein under medical supervision typically after 6-12 months of elimination, with timing individualized based on severity of initial symptoms. 1, 2

• For more severe presentations, perform an oral food challenge at 9-12 months of age in a hospital setting to assess tolerance development. 2

• Most children with cow's milk allergy eventually develop tolerance, often during childhood or teenage years. 4

Critical Pitfalls to Avoid

• Do not discontinue breastfeeding prematurely when maternal elimination diet can effectively manage symptoms—breastfeeding provides significant benefits beyond nutrition. 1, 2, 3

• Do not implement highly restrictive maternal diets that include multiple food eliminations without confirmed allergies through proper rechallenge testing. 4, 1, 2

• Do not restrict maternal diet during pregnancy as a strategy for preventing food allergy—there is no evidence for benefit and potential harm to fetal development. 4, 7

• Do not use widespread skin prick tests or specific IgE tests for screening purposes in the absence of clinical symptoms, as they have poor predictive value and lead to unnecessary dietary restrictions. 2

• Avoid self-diagnosis and implementation of restricted diets without proper medical evaluation, particularly for common infant symptoms like gastroesophageal reflux and colic that are not typically caused by food allergy. 4

Nutritional Counseling and Growth Monitoring

• All children with food allergy require nutritional counseling and regular growth monitoring to ensure carefully planned allergen-free diets provide sufficient nutrients. 4

• Children with food allergy and their caregivers should receive education on interpreting food labels and recognizing food-allergen ingredients. 4

• Products with precautionary labeling such as "may contain trace amounts" should be avoided due to risk of actual contamination. 4