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Author Spotlight: A Unique Mouse Model of Asphyxia-Induced Cardiac Arrest
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Cardiac arrest caused by diphenhydramine overdose
Tomoya Nishino1, Shinjirou Wakai1, Hiromichi Aoki1
1Department of Emergency and Critical Care Medicine Tokai University School of Medicine Isehara Kanagawa Japan.
Acute Medicine & Surgery
|October 20, 2018
Summary
Diphenhydramine overdose can be fatal, even though it is considered safe. High serum concentrations, like 18.7 μg/mL, are linked to death, necessitating rapid measurement protocols in emergency settings.
Area of Science:
- Toxicology
- Emergency Medicine
- Pharmacology
Background:
- Diphenhydramine is a common over-the-counter antihistamine.
- It is generally considered safe at therapeutic doses.
- High doses can lead to significant toxicity.
Observation:
- A 45-year-old male presented with altered consciousness and cardiac arrest following a suspected drug overdose.
- The patient required venoarterial extracorporeal membrane oxygenation (VA-ECMO) support.
- Arterial blood gas revealed mixed acidosis, and ECG showed junctional rhythm with complete right bundle branch block.
Findings:
- The patient experienced a gradual decline in blood pressure and expired on the third hospital day.
- Post-mortem serum analysis revealed a diphenhydramine concentration of 18.7 μg/mL upon arrival.
Implications:
- Diphenhydramine exhibits dose-dependent toxicity, with high concentrations potentially leading to mortality.
- This case underscores the critical need for caution in managing diphenhydramine overdose.
- Prioritizing the development of rapid diphenhydramine measurement protocols in emergency departments is essential for timely intervention.
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