How should acute ingestion of Bispyribac‑sodium 10% suspension concentrate be managed?

Management of Bispyribac-Sodium 10% SC Poisoning

Immediate Stabilization and Supportive Care

The primary management of bispyribac-sodium poisoning is aggressive supportive care with focus on airway protection, hemodynamic monitoring, and seizure management, as no specific antidote exists. 1

Critical First Steps

• Secure the airway immediately and provide respiratory support, particularly in patients with reduced Glasgow Coma Score (GCS), as this is the foundational step in poisoning management 1
• Contact your regional Poison Control Center immediately (1-800-222-1222 in the US) while initiating treatment for case-specific guidance from medical toxicologists 1
• Establish intravenous access for fluid resuscitation and medication administration 1
• Monitor vital signs continuously including blood pressure, heart rate, oxygen saturation, and cardiac rhythm 1

Gastrointestinal Decontamination Considerations

• Activated charcoal may be considered only if the patient presents within 1-2 hours of ingestion AND has a protected airway; the standard dose is 1-2 g/kg body weight 1
• Do NOT perform gastric lavage due to lack of proven benefit and significant risks including aspiration pneumonia, dysrhythmias, and esophageal perforation 1
• Do NOT induce emesis with ipecac as it is no longer recommended and increases aspiration risk 1
• Do NOT administer anything by mouth including water or milk unless specifically directed by poison control, as this may cause emesis and aspiration without proven clinical benefit 2

High-Risk Clinical Features Requiring Intensive Monitoring

Neurological Complications

• Monitor closely for altered mental status and seizures, which are the most concerning early complications 1, 3
• Patients with reduced GCS on presentation require immediate intensive care, as all three deaths in the largest case series occurred in patients with reduced GCS (3,12, and 13) within 6 hours of ingestion 3
• Prepare for seizure management with benzodiazepines readily available, as tonic-clonic seizures occurred in fatal cases 3

Cardiovascular Complications

• Asystolic cardiac arrest is the primary cause of death, occurring at 5-15 hours post-ingestion in fatal cases 3
• Implement immediate life-support measures including CPR according to American Heart Association protocols if cardiorespiratory arrest occurs 2
• Correct critical metabolic derangements (hypotension, dysrhythmias, hypoxia) using standard resuscitation protocols 1

Clinical Course and Prognosis

• The majority of patients develop self-limiting upper gastrointestinal symptoms with a median hospital stay of 3 days 3
• The case fatality ratio is approximately 1.81% (95% CI 0.32-5.8%), which is relatively favorable compared to other commonly used herbicides 3
• Significant poisoning manifests within 6 hours of ingestion; patients who remain stable beyond this timeframe typically have good outcomes 3
• Plasma bispyribac concentrations do NOT predict severity or mortality, likely due to toxicity from non-bispyribac components (solvent or surfactant polyethylene glycol) in the formulation 3

Critical Pitfalls to Avoid

• Do NOT delay airway management while attempting decontamination procedures 1
• Do NOT delay EMS activation to attempt home interventions 2
• Do NOT assume single-agent ingestion—mixed ingestions (particularly with ethanol, which occurred in fatal cases) are common and require broader toxicological assessment 1, 3
• Do NOT rely on plasma bispyribac levels to guide clinical decision-making, as they do not correlate with outcomes 3

Specific Monitoring Parameters

• Assess hepatic function as aromatic hydrocarbons in the formulation may cause liver injury 1
• Monitor renal function since kidney injury may occur with significant exposure 1
• Provide symptomatic treatment for nausea, vomiting, or abdominal pain as needed 1