What should emergency departments do when treating severe ivermectin overdose in adults?

1. Initial triage and stabilization: secure airway, breathing and circulation

The first priorities in any severe ivermectin toxicity are the standard ABCs: assess airway patency and work of breathing, provide supplemental oxygen and be prepared for ventilatory support if respiratory depression or hypoventilation is present, and treat hemodynamic instability per usual resuscitation protocols — these priorities are emphasized because ivermectin overdose can produce neurologic impairment and respiratory depression that threaten oxygenation ^{[2] [3]}.

2. Rapid history, exposure quantification and toxin identification

Gather weight-based dose history, time and formulation (human vs. veterinary products), co-ingestants, past liver disease and home medications metabolized by CYP3A4; knowing the ingested amount relative to typical therapeutic dosing (example human doses ≈150–200 mcg/kg) helps risk-stratify patients and is crucial because many severe cases have involved veterinary formulations or supratherapeutic amounts ^{[4] [5] [3]}.

3. Decontamination: consider activated charcoal when within the window

Although no universal guideline exists, case reports and a toxicity review note there is no specific antidote and that activated charcoal has been used with apparent benefit in at least some patients by accelerating elimination, so early single-dose activated charcoal should be considered if presentation is within an established gastrointestinal decontamination window and the airway is protected ^[1].

4. Supportive care: neurologic and respiratory management without a specific antidote

Because ivermectin toxicity produces a toxidrome dominated by neurologic signs—confusion, ataxia, seizures in reported cases—and can progress to respiratory compromise, management focuses on supportive measures and symptom control; published toxicology reviews state treatment remains supportive in the absence of a targeted antidote ^{[1] [2] [3]}.

5. Laboratory, monitoring and ICU considerations

Continuous cardiorespiratory monitoring, frequent neurologic checks, and readiness to escalate to intensive care are indicated for severe presentations; ivermectin has a long elimination phase in adults (reported half-life ≈57 hours) and is highly protein‑bound and hepatically metabolized, which supports prolonged observation and monitoring for delayed or recurrent toxicity ^{[6] [1]}.

6. Drug interactions and hepatic considerations that affect management

Ivermectin is extensively metabolized by CYP3A4 and is highly protein bound, so co‑ingested CYP3A4 inhibitors or significant liver disease could increase toxicity risk or prolong clearance; clinicians should review concurrent medications and hepatic function when anticipating the clinical course ^{[6] [7]}.

7. Disposition, reporting and public-health messaging

Admission to an appropriate level of care should be based on clinical severity and the potential for delayed effects; cases of severe overdose and misuse—particularly ingestion of veterinary products—have prompted warnings from health agencies and reviews urging reporting of serious adverse events to toxicovigilance systems, a step ED teams should follow to contribute to public-safety data ^{[3] [1] [5]}.

8. Limitations and alternative viewpoints

Published literature and reviews emphasize that there are no standardized treatment guidelines and limited high‑quality evidence specific to ivermectin overdose management; most recommendations derive from case reports and expert toxicology review rather than randomized trials, and some older population studies of ivermectin mass‑treatment for parasitic disease reported low rates of severe adverse events, underscoring that context (therapeutic dosing in controlled settings) matters when interpreting overdose risk ^{[8] [1]}.