Digoxin Effect vs Toxicity

Toxicology

Recognition

  • Effect: 'reverse tick' ST depression, T inversion, QT shortening
  • Toxicity: any arrhythmia (bradycardia, AV block, atrial tachy with block, bidirectional VT)

Key findings

  • Bidirectional VT strongly suggests digoxin toxicity
  • Cannot judge toxicity from ECG alone — check level + K+

Clinical importance

  • Bidirectional VT → immediate Fab fragments

Management pearls

  • Correct K+, Mg
  • Atropine for bradycardia; avoid calcium in acute toxicity (relative)
  • Digoxin-specific Fab if life-threatening arrhythmia, K+ >5, ingestion >10 mg adult / 4 mg child
WardRound

WardRound

Clinical Decisions in Seconds