Whether infants with lactose intolerance need to take lactase for a long time cannot be generalized, generally speaking, primary and secondary lactose intolerance do not need to take lactase for a long time. Lactose intolerance can be categorized as congenital, primary and secondary. Congenital lactose intolerance is caused by genetic factors and the severity of the symptoms is determined by the degree of lactase deficiency, etc. How serious the condition is generally requires long-term use of lactase. Primary lactose deficiency is the most common type of lactose intolerance, according to the enzyme deficiency of different degrees of symptoms, with dietary adjustments and intake improvement will be significantly improved, generally do not need to eat long-term lactase. Secondary lactose intolerance is due to infection, drugs, intestinal surgery, allergies and other causes of small intestinal mucosal damage, resulting in lactase secretion disorders, which in turn cause lactose intolerance, when the removal of the original disease can often be improved, and do not need to take long-term lactase. When the baby appears the symptoms of lactose intolerance, should go to the regular hospital in time to deal with, and under the guidance of the doctor for treatment.