Some babies are intolerant to milk protein, the most common manifestation of which is diarrhea. Some babies also have skin rashes, and some can have a combination of respiratory symptoms, manifested as coughing and wheezing. Some babies may have a combination of respiratory symptoms, such as coughing and wheezing. In severe cases, babies may not gain weight or even have blood in their stools. The main reason for milk protein intolerance is that the baby is allergic to certain components of milk protein. To solve this problem, avoid a milk protein diet or switch to a moderately hydrolyzed protein formula. If moderately hydrolyzed protein formula does not solve the problem, switch to deeply hydrolyzed protein formula. If that still doesn’t work, switch to amino acid powders, which can solve the problem of milk egg intolerance.