Lactose intolerance is a more common disease in infants and young children, for more than a year old baby suddenly lactose intolerance does not have to stop milk powder, can be appropriate oral lactase, for the effect is not good need to be replaced with lactose-free milk powder. Lactose intolerance is more common in infants and young children, it is due to the baby’s digestive tract lactase enzyme quantity or activity is insufficient, eating lactose or lactose-containing formula milk, can not be thoroughly digested and decomposed, and then appeared in the diarrhea, bloating and other abdominal discomfort, some babies can also vomit and other symptoms. For more than a year old baby occurs the above situation does not necessarily have to stop the milk powder, can be used under the guidance of the physician lactase, can be appropriate to increase the ability of the intestinal tract to lactose digestion, and to observe the related symptoms have not improved. If the effect is not good, such as diarrhea is still obvious, or there is no weight gain, etc., need to be replaced by lactose-free milk powder. Consultation with a specialist for intervention is recommended if necessary.