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Complete atrioventricular block due to ingestion of Visine eye drops

Omar Afify1, Abdul-Rahman M Suleiman2, Hassan G Mohamed3

  • 1Internal Medicine, Wayne State University School of Medicine, Detroit, Michigan, USA oafify@wayne.edu.

BMJ Case Reports
|May 13, 2021
PubMed

Insights

Tetrahydrozoline, found in Visine eye drops, can cause severe heart problems like complete heart block when ingested. This case highlights the risks of accidental or intentional tetrahydrozoline (Visine) overdose, especially in adults.

Area of Science:

  • Toxicology
  • Cardiology
  • Ophthalmology

Background:

  • Tetrahydrozoline is an imidazoline derivative used in ophthalmic and nasal decongestants.
  • Accidental ingestion is common in children, but adult cases are increasing.
  • Systemic effects include bradycardia and hypotension via central alpha-adrenergic receptor activation.

Observation:

  • A 76-year-old male ingested 120 mL of 0.05% tetrahydrozoline (Visine eye drops) in a suicide attempt.
  • The patient presented with bradycardia 24 hours post-ingestion.
  • Initial ECG showed complete heart block and QT prolongation.

Findings:

  • The case report details the first instance of complete heart block following tetrahydrozoline consumption.
  • Persistent first-degree atrioventricular block and QT prolongation were observed in subsequent ECGs.
  • Ingestion of a large volume of tetrahydrozoline led to significant cardiovascular compromise.

Implications:

  • This case underscores the potential for severe cardiac toxicity from tetrahydrozoline overdose.
  • It highlights the need for increased awareness of tetrahydrozoline's systemic effects, particularly in adults.
  • Clinicians should consider tetrahydrozoline poisoning in patients presenting with unexplained bradycardia and heart block.

Keywords:
arrhythmiasdrug misuse (including addiction)poisoningtoxicology

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