Four-month-old babies do not poop for several days is mostly related to functional constipation in infants, the treatment method has general treatment, medication and so on. 1. general treatment: four months baby a few days do not poop, may be the existence of functional constipation, can increase the amount of water, abdominal massage, etc., in order to stimulate intestinal peristalsis, promote defecation. 2. medication: when the baby functional constipation symptoms are serious, can follow the doctor’s instructions to give lactulose and other laxatives to improve stool properties, so that the bowel movement. Can also use bifidobacterium bifidum triple live bacterial powder and other microecological agents, regulating intestinal flora imbalance, so as to improve the symptoms of functional constipation in infants. If necessary, corkscrew can be given to help defecation. Four-month-old babies do not poop for several days, may also be organic constipation, need to consult a doctor in time, surgical treatment. It is recommended that the four-month-old baby does not poop for several days, timely medical treatment, active treatment. The above medications should be used in accordance with medical advice.