In infants with cow's milk protein allergy and gastroenteritis, which type of formula is recommended as a trial?

• A. Hydrolyzed formula
• B. Soy-based formula
• C. Regular cow's milk
• D. Rice-based formula

Answer: (A)

In cow milk protein allergy, the goal is to minimize exposure to intact cow milk proteins while still meeting the infant’s nutritional needs. Extensively hydrolyzed formulas contain proteins that have been broken down into very small peptides, which dramatically reduces their ability to trigger an allergic response. This makes hydrolyzed formula the preferred trial option when formula feeding is needed, even when gastroenteritis is present, because it tends to be better tolerated and can help reduce GI symptoms while providing adequate nutrition. Soy-based formulas are usually avoided in CMPA due to potential cross-reactivity and intolerance in many infants. Regular cow's milk must be avoided, and rice-based formulas are not routinely recommended for CMPA due to limited evidence and concerns like arsenic exposure. If symptoms persist on hydrolyzed formula, an amino acid–based formula may be considered.