Paraquat poisoning management

Abstract

Paraquat a rapidly acting, nonselective herbicide is a leading cause of fatal poisoning in many parts of Asia. After rapid absorption, paraquat is concentrated inside many cells where it undergoes redox cycling. Clinical features are largely due to intracellular effects. Paraquat is actively concentrated into lung tissue leading to pneumonitis and lung fibrosis. Paraquat also causes gastrointestinal, renal, and liver injuries. Activated charcoal and Fuller's earth can minimize further absorption. Gastric lavage is contraindicated. Hemodialysis and hemoperfusion are unlikely to change the clinical course. The use of immunosuppression with dexamethasone, cyclophosphamide, and methylprednisolone evidence for efficacy is weak. Antioxidants such as acetylcysteine and salicylate used as free radical scavenging might be beneficial. The case fatality is very high in this herbicide due to the lack of effective treatment options.