Cow milk protein allergy in babies: signs and feeding

What does the evidence show for cow milk protein allergy in babies?

• Milk allergy involves an immune response to protein; lactose intolerance involves digestion of a milk sugar. The conditions require different feeding decisions. A lactose-free product can still contain cow milk proteins, so the label does not establish suitability for milk allergy. 1
• Milk allergy can have different patterns, including rapid skin or respiratory symptoms and delayed gastrointestinal symptoms. Blood in stools, vomiting, or poor growth needs assessment, but fussiness or a stool photograph alone is not enough to establish the cause. 2
• Anaphylaxis is a medical emergency. A reaction involving breathing difficulty, throat or tongue swelling, faintness, or collapse needs emergency services and the prescribed emergency allergy plan, if one exists. Do not wait for a routine feeding appointment. 3
• The 2024 WAO formula recommendations are conditional and based on very low certainty evidence. Choice depends on the individual infant, previous reactions, availability, and cost. This is a reason to plan with the care team rather than label one product the best for every baby. 4
• Partially hydrolyzed routine formula, extensively hydrolyzed hypoallergenic formula, and amino acid formula are different categories. A can labeled gentle is not enough information for an infant with confirmed allergy. Have the pediatric team identify the intended category and product. 5
• A dietary restriction requires a nutrition plan, including for a breastfeeding parent if a clinician recommends eliminating cow milk protein. Breastfeeding does not automatically need to stop. The team should clarify the purpose, duration, and follow-up of any elimination plan. 2

Questions to discuss with your care team

When should I call my provider about cow milk protein allergy in babies?

Breathing difficulty, tongue or throat swelling, collapse, or a severe reaction after feeding: call 911 and follow the prescribed emergency plan.,Blood in stools, repeated vomiting, poor intake, or poor growth needs prompt pediatric assessment.,Marked sleepiness or reduced urine with feeding problems needs urgent care. If you are ever unsure which side of the line you are on, make the call. Obstetric teams handle these check-ins as routine, not as overreacting.