At present, there is no special antidote for paraquat poisoning, and the death rate can be as high as 70% or more. The prognosis is related to the amount of paraquat ingested by the patient, as follows: 1. light: paraquat intake <20mg/kg, patients have less obvious symptoms except gastrointestinal symptoms, and most patients can recover completely; 2. medium to heavy: paraquat intake is 20-40mg/kg, patients have more obvious gastrointestinal symptoms. Patients with gastrointestinal symptoms are more obvious, multi-system involvement can appear, kidney function damage and liver function damage can appear in 1-4 days, lung damage can appear in a few days to 2 weeks, most of them die in 2-3 weeks due to pulmonary failure; 3. violent disease: paraquat intake is >40m/kg, such patients can have serious gastrointestinal symptoms, die in 1-4 days due to multi-organ failure, very few of them survive.