Digoxin toxicity

Digoxin toxicity
Digoxin toxicity
Classification and external resources

Digitalis purpurea drawings by Franz Köhler
ICD-10 T46.0
ICD-9 972.1

Digoxin toxicity is a poisoning that occurs when excess doses of digoxin (from plants of the genus Digitalis) are consumed acutely or over an extended period. The classic features of digoxin toxicity are nonspecific: fatigue, blurred vision, change in color vision (eg. "yellow" vision"), anorexia, nausea, vomiting, diarrhea, abdominal pain, headache, dizziness, confusion, delirium.

Characteristic EKG changes include bradycardia (the most frequent vital sign abnormality in toxicity), a prolonged PR interval. Anaccelerated junctional rhythm or bidirectional ventricular tachycardia suggests digoxin toxicity until proven otherwise.

Contents

Classification

Digoxin toxicity is often divided into acute or chronic. The therapeutic level for digoxin is 0.5-0.8 ng/mL. Low serum potassium increases the risk of digoxin toxicity and cardiac dysrhythmias. The classic arrhythmia is a paroxysmal atrial tachycardia with block. Digoxin toxicity occurs because it is very easy to overdose. Overdose commonly occurs because it's therapeutic effect works only within a very narrow window. The most common source of digoxin is from the Foxglove plant.

Symptoms

Symptoms include hypersalivation, fatigue, nausea/vomiting, changes in heart rate and rhythm, loss of appetite (anorexia), diarrhea, visual disturbances (yellow or green halos around objects), confusion, dizziness, nightmares, agitation, and/or depression, as well as a higher acute sense of sensual activities.

Treatment

Digoxin immune Fab used to treat digoxin toxicity

The primary treatment of digoxin toxicity is digoxin immune Fab. Digoxin should not be given if the apical heart rate is below 60 BPM (beats per minute).

Other treatment that may be tried to treat life-threatening arrhythmias, until digoxin Immune Fab is acquired are magnesium, phenytoin, andlidocaine.[1]

Atropine is also used in cases of bradyarrhythmias.

References