Abstract: 【Abstract】The incidence of paraquat intoxication in Taiwan is unknown; however it is not uncommon in a clinical setting. The high mortality rate of paraquat intoxication results from its high acute toxicity, low lethal dose, and lack of effective therapies. After ingestion, absorption of paraquat is rapid. Once paraquat invades cells, it activates reactive oxygen species, and then causes lipid peroxidation, activation of NF-kB, mitochondrial damage and apoptosis, finally leading to multiorgan damage. The clinical manifestations of paraquat intoxication depend upon the dose of ingestion. Plasma concentration of paraquat, urine dithionite test and clinical presentation are good predictors of outcome. Medical management includes supportive treatment and gastrointestinal decontamination with active charcoal. Hemodialysis and hemoperfusion can enhance elimination of paraquat; however, the benefit is limited except for early initiation after ingestion. Several new therapies have been proposed, including immunosuppression with glucocorticoids and cyclophosphamide. Antioxidants such as acetylcysteine and salicylate might be effective because of free radical scavenging, anti-inflammatory action and NF-kB inhibition. This review provides the mechanisms, clinical features, diagnosis and latest medical progress in the treatment of paraquat intoxication.

Key words: paraquat, hemodialysis, hemofiltration, immunosuppressants, antioxidants