Children with diarrhea and watery diarrhea are considered to be related to the influence of the environment, intestinal infections, allergies and other factors. General treatment can be given first to stop diarrhea, not relieved and then given anti-infective, antidiarrheal, probiotic drugs for treatment. 1. Influence of environment: frequent exposure to low temperature, cold and wet environment, improper diet or improper use of antibiotics may cause watery diarrhea. It is recommended to detach from the environment, adjust the diet and stop the use of suspicious drugs, which may improve the condition. If not relieved, can follow the doctor’s advice to give montelukast, can adsorb the water inside the intestine, reduce the symptoms of diarrhea. 2. Intestinal infections: viral or non-invasive bacterial infections in the intestinal tract, resulting in damage to the intestinal mucosa, intestinal peristalsis accelerated, can cause watery stools. Under doctor’s guidance, Montelukast with probiotics (e.g. Bacillus subtilis bacillus granules) can help to improve the symptoms. 3. Allergic factors: Smaller babies who are allergic to milk proteins or have lactose intolerance can cause watery stools. It is recommended to clarify the diagnosis, change the milk powder, and give oral rehydration or intravenous rehydration if necessary, to correct the situation of water electrolyte disorders. Children’s diarrhea and water may also have other causes, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, to give targeted treatment or treatment.