Patients taking organophosphorus pesticide poisoning should be timely gastric lavage, through gastric lavage can quickly remove the poison in the stomach, to prevent further deepening of poisoning, the earlier the effect of gastric lavage the better, especially in the 4-6 hours or less gastric lavage, generally can maximize the effect of detoxification, and the relative complications are relatively small. However, gastric lavage should be contraindicated if strong acids or bases, potassium permanganate or other strong corrosive substances are ingested. If the intake of strong corrosive substances will cause acute damage to the gastric mucosa, it may cause gastric perforation when inserting a gastric tube, in addition, if a large amount of liquid is entered during gastric lavage, it is easy to cause rupture or perforation of the stomach. Patients with severe esophageal varices and patients with active gastric bleeding should also be prohibited from gastric lavage, because when such patients undergo gastric lavage, it may cause severe bleeding, resulting in hemorrhagic shock, which may be life-threatening. In addition, gastric lavage in comatose patients should be performed with caution, as it may cause aspiration leading to asphyxiation of the patient. Caution should also be exercised in patients with severe heart disease as gastric tube insertion may cause irritation and serious cardiac arrhythmia.