A 15-year-old-female admitted after ingesting 5 milligrams of digoxin, presented atrial tachycardia with 2.0 degree atrioventricular block and frequent ventricular premature complexes. Serum digoxin determination at admission was 16 ng/ml. Two hours following the administration of 2 amp of Fab antidigoxin (160 milligrams) the arrhythmias disappeared and remained asymptomatic until discharge.