Gastroenteritis, also known as stomach flu, mainly occurs due to simultaneous infections in the stomach and intestinal mucosa by bacteria or viruses. The primary clinical symptoms are nausea, vomiting, abdominal pain, diarrhea, and watery stools—some experience it five or six times a day, and others more than ten times a day. Increased frequency of stools can lead to symptoms of dehydration. Excessive loss of body fluids can cause electrolyte imbalance and dehydration, presenting symptoms such as pale complexion, cold limbs, fever, and decreased blood pressure. In such cases, it is essential to go to the hospital for intravenous fluids as soon as possible. Oral rehydration solutions can also be used, but if the patient experiences severe nausea and vomiting, intravenous administration of glucose, saline, and potassium chloride is necessary. (Please rehydrate under the guidance of a doctor.)