Loperamide toxicity

Background

• Loperamide is widely used nonprescription anti-diarrheal medication
• Increasing reports of intentional overdose at very high doses either for euphoric effects or to attenuate symptoms of opioid withdrawal
• Has a wide margin of safety, largely due to extremely low bioavailability (0.3%)

Clinical Features

• May have features of conventional opioid toxicity

Loperamide-induced cardiac toxicity

• Often young
• May present in cardiac arrest or with recurrent syncope in conjunction with ECG agnormalities

Differential Diagnosis

Sedative/hypnotic toxicity

• Absinthe
• Barbiturates
• Benzodiazepines
  • Flunitrazepam (Rohypnol)
• Chloral hydrate
• Gamma hydroxybutyrate (GHB)
• Baclofen toxicity
• Opioids
  • Lomotil toxicity
  • Loperamide toxicity
• Toxic alcohols
  • Ethanol
  • Ethylene glycol
  • Isopropyl alcohol
  • Methanol
• Xylazine toxicity

Evaluation

ECG Findings

• QT prolongation
• QRS widening
• Ventricular dysrhythmias

Management

• Supportive care / standard ACLS
• Consider:
  • Overdrive pacing
  • Intravenous lipid emulsion
  • Extracorporeal membrane oxygenation

See Also

• Loperamide