Fatal Large-Volume Mouthwash Ingestion in an Adult: A Review and the Possible Role of Phenolic Compound Toxicity

Objective: To describe a case of fatal mouthwash ingestion and review possible sources of toxicity. Design: Case report. Setting: Veterans Administration Medical Center. Patient: Single patient with massive mouthwash ingestion. Main results: This patient was a 45-year-old man who developed cardiovascular collapse and multiorgan system failure following a massive ingestion of mouthwash (almost 3 liters). His presentation was remarkable for a profound anion-gap metabolic acidosis and a significant osmolar gap. No other co-ingestants were identified, and he expired despite full supportive care including dialysis and mechanical ventilation. An autopsy failed to identify any other cause of death. Nonalcoholic ingredients of this mouthwash are phenolic compounds (eucalyptol, menthol, and thymol), and large-volume mouthwash ingestion will produce exposure in the reported toxic range of these ingredients. Conclusions: When ingested in large quantities, the phenolic compounds in mouthwash may contribute to a severe anion-gap metabolic acidosis and osmolar gap, multiorgan system failure, and death. These compounds, in addition to alcohol, may account for the adverse effects associated with massive mouthwash ingestion.