A cow’s milk protein allergy results from the baby’s immune system reacting to the protein in cow’s milk. Milk protein allergy is by far the most common food allergy in infancy.
If you suspect that your baby is allergic to the protein in cow’s milk, discuss the possibility with your baby’s doctor. As you are formula feeding, the doctor might recommend a special, hypoallergenic† formula with extensively hydrolyzed protein, like Similac® Alimentum®.