Approach to procainamide infusion in adults

AVRT: atrioventricular reentrant tachycardia; IV: intravenous; NAPA: N-acetylprocainamide; QTc interval: corrected QT interval; VT: ventricular tachycardia.

* Some sources describe a maximum dose of 17 mg/kg^[1]. Higher infusion rates are more likely to cause hypotension. Refer to the drug information included within UpToDate for specific dose adjustments for older patients and those with kidney or liver dysfunction.

¶ Maintenance infusion of procainamide is associated with toxicity (eg, QRS and QTc interval prolongation, torsades de pointes in susceptible patients); seek alternative agents for maintenance of sinus rhythm. If procainamide is selected for ongoing treatment, may administer at 1 to 4 mg/min. Some experts use higher infusion rates (eg, 6 to 10 mg/min). If infusion of procainamide extends beyond 12 to 24 hours, measure QRS duration, QTc interval, and procainamide levels twice daily. Signs of toxicity include QRS prolongation of more than 50% compared with QRS in sinus rhythm at the onset of therapy or a QTc interval greater than normal sex-specific values. Procainamide toxicity may begin at levels >9 mcg/mL but varies considerably between patients. Some experts also measure NAPA levels, but toxic and therapeutic levels are not well-defined.

Δ Alternative agents and approaches available for management depend on the specific tachycardia. For details, refer to UpToDate content on specific arrhythmias (eg, AVRT, preexcited atrial fibrillation, wide-complex tachycardia).