Gastric lavage can be performed by drinking water or by machine. In case of food poisoning or organophosphorus pesticide poisoning, the presence of toxins in the stomach can be reduced by gastric lavage. For people who are relatively sober, simple washing can be done by drinking a lot of water and then spitting out the contents of the stomach. This method allows the contents of the stomach to be flushed clean and reduces the possibility of toxic substances entering the body’s blood circulation. For people who are already unconscious and confused, the machine method of gastric lavage can be used. Machine gastric lavage involves injecting gastric lavage fluid into the stomach, then staying for a period of time before pumping the fluid out through the machine and continuously circulating until the stomach contents are flushed clean. It should be noted that patients with gastric ulcer, gastric perforation, gastric cancer and other diseases should be cautiously lavaged to avoid aggravating the condition.