Infant milk protein allergy (CMPA), caused by the baby’s body’s immune system overreacting to milk proteins, is the most common food allergy in the first year of life, with a prevalence of up to 5%. Food allergy is mainly for protein allergy, and many foods contain protein, but milk protein allergy is the first to be detected and has the highest incidence. There are three main symptoms of milk protein allergy in babies. The first is digestive symptoms, where the baby has recurrent vomiting, diarrhea, bloating, constipation, and blood in the stool. The second is skin symptoms, the baby will appear eczema, acute hives. The third is the respiratory symptoms, the child has frequent unexplained coughing and sneezing, and severe asthma. Because of milk powder allergy babies are irritable, often cry, sleep disturbance, affect the development, appear anemia, etc.. Vomiting after eating milk may also lead to aspiration pneumonia, which may require injections and medication. If your baby has the above three symptoms, consider milk protein allergy. Switch to amino acid formula or deeply hydrolyzed formula for formula-fed babies, and avoid allergic foods such as milk, eggs, peanuts, fish and shrimp for babies with complementary foods. Breastfed babies can also have allergy symptoms and mothers should also avoid allergy-prone foods.