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Propafenone and propranolol dual toxicity
Moonis Farooq1, Faisal Qureshi1, Wael Kamkoum1
1Emergency Department King Hamad University Hospital Busaiteen Kingdom of Bahrain.
Journal of the American College of Emergency Physicians Open
|November 4, 2020
Summary
A dual overdose of propranolol and propafenone caused severe toxicity, including seizures and altered consciousness. Prompt treatment with sodium bicarbonate and other supportive measures led to a full recovery.
Area of Science:
- Cardiology
- Clinical Toxicology
- Pharmacology
Background:
- Propranolol is a beta-receptor antagonist; propafenone is a Class 1c anti-arrhythmic with sodium channel blockade properties.
- Dual overdoses involving these agents are rare but can lead to significant systemic toxicity.
Observation:
- A 52-year-old female presented with hypotension, generalized seizures, and reduced consciousness after ingesting 500 mg propranolol and 1.5 g propafenone.
- The patient exhibited signs of combined beta-blocker and propafenone toxicity.
Findings:
- Treatment involved high-dose insulin, sodium bicarbonate (NaHCO3), glucagon, atropine, and dopamine.
- The patient showed clinical improvement, including increased alertness and normalization of ECG findings.
Implications:
- Early administration of sodium bicarbonate is crucial for patients exhibiting signs of sodium channel blockade toxicity.
- This case highlights the successful management of a complex dual drug overdose with a multi-faceted treatment approach.
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