Paraquat poisoning: Acute poisoning caused by accidental or suicidal oral ingestion. Oral intoxication by accidental ingestion and suicide is common, and intravenous injection through the skin, respiratory tract, or intravenous injection is rare. The mechanism of poisoning is not completely clear, but it may be that paraquat causes multiple organ failure through lipid peroxidation, mitochondrial dysfunction, necrosis and apoptosis. Paraquat poisoning is common in oral poisoning, patients mostly have local symptoms, such as burning sensation in the mouth, nausea, vomiting, abdominal pain, diarrhea, vomiting blood, black stools, kidney damage can be hematuria, oliguria, lung damage, there are coughing, chest tightness, shortness of breath, lips, face and nail beds bruising, respiratory difficulties, etc.; local contact poisoning is mainly for the skin symptoms, the patient mostly have skin erythema, blisters, ulcers. Eye damage has burning sensation and ulceration of conjunctiva and cornea. Signs and symptoms of paraquat poisoning are usually manifested within 12 hours after poisoning. There is no specific antidote for paraquat poisoning, and the main symptomatic treatment is symptomatic.