For children with gastroenteritis, we first treat the gut with probiotics, such as oral bifidobacterium or lactobacillus acidophilus. Then, we can provide gastrointestinal mucosal protectants, such as montmorillonite powder. At the same time, since gastroenteritis may cause dehydration and electrolyte disorders, it is necessary to replenish fluids and electrolytes, commonly using oral rehydration salts. If the gastroenteritis is suspected to be caused by a viral infection, some antiviral medications should be taken orally. If it is considered to be caused by a bacterial infection, oral antibiotics for anti-infection treatment, such as cephalosporins or penicillins, should be administered.