Children are prone to vomiting and diarrhea, and the greatest danger they pose is that it leads to dehydration. So what are the signs of dehydration? The signs and symptoms of dehydration are: little or no urine, depression, poor skin elasticity, sunken eye sockets, sunken fontanelle, dry mucous membrane of the mouth and lips, and irritable thirst for drinking. The most convenient way to prevent and treat dehydration is oral rehydration fluid, as long as the child can drink, then how much can and how much, but it should be noted that and ordinary plain water is not good, easy to cause electrolyte disorders, it is generally best to take hypotonic oral salts III (commercially available is generally a generation of products, high osmotic pressure, can aggravate diarrhea), the liquid can prevent and correct dehydration, and because of the low osmotic pressure, can reduce the stool frequency, but for children who vomit frequently and cannot enter water orally still need timely intravenous rehydration.