Drug interactions between adenosine and Betapace AF

GENERALLY AVOID: Class IA (e.g., disopyramide, quinidine, procainamide) and class III (e.g., amiodarone, dofetilide, sotalol) antiarrhythmic agents can cause dose-related prolongation of the QT interval. Theoretically, coadministration with other agents that can prolong the QT interval may result in elevated risk of ventricular arrhythmias, including ventricular tachycardia and torsade de pointes, because of additive arrhythmogenic potential related to their effects on cardiac conduction. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia). In addition, the extent of drug-induced QT prolongation is dependent on the particular drug(s) involved and dosage(s) of the drug(s). MANAGEMENT: The concurrent use of class IA or class III antiarrhythmic agents with other medications that can prolong the QT interval should preferably be avoided unless benefits are anticipated to outweigh the risks. Caution and clinical monitoring are recommended if these agents are prescribed together, especially to patients with underlying risk factors. Patients should be advised to seek medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, palpitations, or syncope.