What is the antidote for propaquizafop (5%) combined with oxyfluorfen?

Antidote of propaquizafop 5% + oxyfluorfen

• There is no specific antidote for either propaquizafop or oxyfluorfen; treat with immediate decontamination and aggressive supportive care to prevent organ failure and death. 1, 2

What to do now (prioritizing morbidity, mortality, QOL)

1. Immediate actions

   • Remove from exposure; strip contaminated clothing; copious soap-and-water skin/eye irrigation.
   • If recent ingestion and airway protected: single-dose activated charcoal 1 g/kg (max 50 g). Do not induce emesis. 2

2. Supportive management (ICU-ready)

   • Airway/breathing: oxygen, early intubation if CNS depression/aspiration risk.
   • Circulation: IV fluids; vasopressors if needed; continuous cardiac monitoring.
   • Labs and monitoring: CMP (focus AST/ALT, bilirubin), INR/PT, CBC (anemia), lactate, CK, UA; repeat every 6–12 h in first 24–48 h for evolving hepatotoxicity/hem biosynthesis interference described with oxyfluorfen. 1
   • Hepatoprotection: no proven antidote; consider early toxicology/hepatology consult; manage acute liver injury per standard protocols (coagulopathy, encephalopathy). 1

3. What not to use

   • No role for pralidoxime/atropine (not organophosphate nerve agents). 3
   • No evidence for lipid emulsion, dialysis, or specific chelators in these herbicides; reserve lipid emulsion for local anesthetic systemic toxicity per antidote-stocking guidance. 2

4. Red flags needing escalation

   • Rising transaminases/coagulopathy, jaundice, encephalopathy, GI bleeding (fulminant hepatic failure risk). 1
   • Hemolysis/anemia or severe metabolic acidosis.

Evidence notes

• Oxyfluorfen human toxicity: case evidence shows acute hepatic injury; explicitly states no specific antidote and emphasizes prevention and aggressive decontamination/supportive care. 1
• Antidote stocking guidelines reinforce that for many xenobiotics without antidotes, rapid decontamination and supportive care are lifesaving; lipid emulsion is not broadly recommended outside defined indications. 2

Pitfalls to avoid

• Delayed decontamination and delayed airway control.
• Inappropriate use of organophosphate antidotes (atropine/oximes). 3
• Assuming dialysis will help (high protein binding and large volumes of distribution likely limit benefit).