What is Digoxin and how does it work?

• Cardiac glycoside extracted from the Foxglove plant (Digitalis Lanata)
• Blocks the Na+/K+ ATPase in the myocardium

Potential uses of digoxin

• Atrial fibrillation(lowers heart rate by increasing refractory period
• Heart failure (due to + Inotropy)

Digoxin toxicity

Check Digoxin level
GI: N/V/anorexia/diarrhea
Visual: blurred vision, yellow/green discoloration (Xanthopsia), haloes
CV: palpitations, syncope, dyspnea
CNS: cofusion/dizziness/fatigue/delirium

Most common EKG findings of Digoxin use 

• PVC (most common finding)
• Heart block
• U Waves
• Scooped ST-depressions (the Salvador Dali mustache)
• Combo of SVT with slow ventricular response (eg: atrial tachycardia with block)

*From Rapid Interpretation of EKG’s copyright © 2016 COVER Publishing Co. Inc.

Treatment

• Discontinue Digoxin!
• Dig fab fragments (Digibind) if life threatening/HD unstable arrthymia,
• hyperkalemia (K>5.5), or end-organ damage from hypoperfusion (eg: renal failure/AMS)
• Remember that HYPOkalemia worsens toxicity (less potassium=more digoxin binding at Na/K ATPase) and digoxin toxicity causes HYPERkalemia (if Na/K+ ATPase not working, cant pump potassium into the cell)