Don’t treat “survival” as a safety net: after ingesting paraquat or inhaling carbon monoxide, emergency care can save lives, but it rarely preserves lung or brain function.

33. Don’t treat “survival” as a safety net: after ingesting paraquat or inhaling carbon monoxide, emergency care can save lives, but it rarely preserves lung or brain function.

Cost: No cost involved. It simply helps you understand this reality up front.

In plain terms: There is no antidote for paraquat. Gastric lavage is not recommended, and neither hemofiltration nor dialysis alters its disease progression. Paraquat actively enters lung tissue against its concentration gradient, causing pneumonia and pulmonary fibrosis, while also damaging kidneys and liver. Among 257 cases treated at ten hospitals in Bangladesh, the mortality rate reached 43.2%. Carbon monoxide produces similar outcomes: six weeks after exposure, 46.1% of patients receiving normal oxygen still suffered cognitive impairment, compared to 25.0% of those receiving hyperbaric oxygen therapy. No treatment pathway yields a completely clean outcome; the most common result is lasting health complications.

Benefit: A systematic review on paraquat poisoning highlights its extremely high mortality rate, stemming from its intrinsic toxicity and lack of effective treatments. Paraquat is actively transported into lung tissue against its concentration gradient, resulting in pneumonia, pulmonary fibrosis, kidney and liver damage. The review explicitly advises against gastric lavage; hemofiltration and dialysis are unlikely to alter clinical outcomes. Evidence supporting corticosteroids or immunosuppressants remains weak. It also notes that mortality rates remain high across all centers despite varying treatment approaches. In Bangladesh, 257 out of 1,420 cases admitted to ten tertiary hospitals between 2013 and 2024 resulted in death (43.2%). Common symptoms included lower limb swelling due to acute kidney failure (71.2%), vomiting (65.8%) and abdominal pain (58.0%). Another randomized, double-blind trial involving 76 patients per group examined acute carbon monoxide poisoning; six weeks later, 25.0% of those receiving hyperbaric oxygen therapy and 46.1% of those receiving normal oxygen still had cognitive impairments (P=0.007; adjusted OR 0.45, 95% CI 0.22–0.92). A separate study of 73 patients found 30% developed cognitive impairments and 12% showed hyperintense signals in white matter on brain imaging. Since July 1, 2014, China has banned the registration and production of paraquat aqueous solutions; sales and usage ceased by July 1, 2016. As of September 26, 2020, soluble concentrate formulations are also prohibited nationwide. Official documents cite frequent suicide attempts involving paraquat as the primary reason for these strict controls.

Evidence grade: B

Sources: Gawarammana IB, Buckley NA (2011). Medical management of paraquat ingestion. British Journal of Clinical Pharmacology, 72(5), 745-757. <https://doi.org/10.1111/j.1365-2125.2011.04026.x>; Chowdhury FR et al. (2026). Clinical and Laboratory Profile of Paraquat Poisoning: A Toxicological Crisis in Bangladesh. American Journal of Tropical Medicine and Hygiene, 115, 176-182. <https://doi.org/10.4269/ajtmh.25-0719>; Weaver LK, Hopkins RO, Chan KJ, et al. (2002). Hyperbaric oxygen for acute carbon monoxide poisoning. New England Journal of Medicine, 347(14), 1057-1067. <https://doi.org/10.1056/NEJMoa013121>; Parkinson RB, Hopkins RO, Cleavinger HB, et al. (2002). White matter hyperintensities and neuropsychological outcome following carbon monoxide poisoning. Neurology, 58(10), 1525-1532. <https://doi.org/10.1212/wnl.58.10.1525>; (2018). (〔2018〕17 ). <https://www.gov.cn/zhengce/zhengceku/2018-12/31/content_5442594.htm>

Notes: Grade B is assigned because these studies involve general poisoning patients rather than solely suicide attempt survivors; the carbon monoxide trial even included accidental poisoning cases. Consequently, observed complication rates cannot be directly interpreted as probabilities specific to suicide attempts. This entry does not compare mortality rates across different treatment methods nor recommend any specific actions. The sole certainty is that no treatment pathway guarantees a completely clean outcome. On-site management of carbon monoxide poisoning is detailed in Section 13, Item 19. For accidental ingestion of pesticides or medications, avoid inducing vomiting and seek medical help while bringing the container along (Section 13, Item 20). Finally, refrain from storing pesticides or sedatives at home (Section 13, Item 25).