Although the herbicide paraquat is not a therapy drug, it is cited in Pneumotox because it is a pulmonary toxin that is still used in suicide attempts in some countries. Typically, paraquat causes acute respiratory failure, ARDS and pulmonary fibrosis in survivors. paraquat may contaminate nutrients, alcoholic beverages and illegal substances of abuse. Paraquat has medical-legal implication as cases of deliberate poisoning by proxy have been reported. Most western countries have now banned paraquat. When in doubt, measurement of paraquat in blood and/or urine is indicated. PMID 1892020 (imaging features) and 27160134