Medication-Induced Arrhythmias Recommendations for Medication-Induced Arrhythmias References that support the recommendations are summarized in Online Data Supplements 52 and 53. Digoxin COR LOE Recommendation I B-NR Administration of digoxin antibodies is recommended for patients who present with sustained VA potentially due to digoxin Medication-induced QT prolongation and torsades de pointes COR LOE Recommendations I B-NR In patients with recurrent torsades de pointes associated with acquired QT prolongation and bradycardia that cannot be suppressed with intravenous magnesium administration, increasing the heart rate with atrial or ventricular pacing or isoproterenol are recommended to suppress the I C-LD For patients with QT prolongation due to a medication, hypokalemia, hypomagnesemia, or other acquired factor and recurrent torsades de pointes, administration of intravenous magnesium sulfate is recommended to suppress the arrhythmia.S10.7-4,S10.7-5 I C-LD For patients with torsades de pointes associated with acquired QT prolongation, potassium repletion to 4.0 mmol/L or more and magnesium repletion to normal values (eg, 2.0 mmol/L) are beneficial.S10.7-6,S10.7-7 Sodium channel blocker related toxicity COR LOE Recommendations IIa C-LD In patients taking sodium channel blockers who present with elevated defibrillation or pacing thresholds, discontinuing the presumed responsible medication or reprogramming the device can be useful to restore effective device therapy.S10.7-8,S10.7-9 III: Harm B-NR In patients with congenital or acquired long QT syndrome, QT-prolonging medications are Recommendation-Specific Supportive Text 1. Typical arrhythmias related to digoxin toxicity include enhanced atrial, junctional, or ventricu- lar automaticity (with ectopic beats or tachy- cardia) often combined with atrioventricular VT that is fascicular or bidirectional in origin is suggestive of digoxin toxicity.S10.7-12 Severe digoxin overdose causes hyperkalemia and cardiac standstill. The diagnosis is established by the combination of characteristic rhythm distur- bances, ancillary symptoms (visual disturbances, nausea, changes in mentation), and elevated serum concentrations. 