If a 4-month-old baby poops after eating milk, it may be physiological diarrhea, or it may be caused by disease, which needs to be further judged according to different situations: a. Physiological diarrhea: If this symptom does not affect the baby’s normal weight gain, and the color and smell of the stool are normal, it is likely that physiological diarrhea has occurred. 4-month-old babies are mostly eating breast milk, and if the mother eats protein or fatty The baby may have physiological diarrhea if the mother eats foods with high protein or fat content. Some mothers add complementary foods to their babies too early and too quickly, so that the baby cannot digest the food completely, or feed irregularly, so that the baby’s gastrointestinal tract cannot form a conditioned reflex to secrete digestive juices regularly, which reduces the digestive function, or the pacifier is contaminated, etc., which can cause the baby to poop after eating milk. If the baby is in good spirits and does not affect normal eating and daily activities, there is generally no need to worry about it, as most of them will ease on their own as they get older. If the diarrhea is more serious, it is recommended to consult a doctor and follow medical advice for symptomatic treatment. Second, the cause of disease: If you have poop after eating milk, and accompanied by abdominal distension, nausea, vomiting, crying or affect the normal feeding situation, may be after the cold gastrointestinal dysfunction, but also may be too much milk, resulting in digestive dysfunction. In addition, some may be intestinal inflammation, such as viral enteritis or bacterial infection caused by enteritis, may appear to eat and poop phenomenon. In addition to the intestinal tract itself, it may also be a complication of other diseases, such as systemic infections when the intestinal tract is also affected. Be sure to combine your child’s systemic symptoms and, if necessary, send your baby’s excreted stool to the hospital for a routine stool examination to assist your doctor in making a differential diagnosis and then treating the problem symptomatically.