Comparative Pharmacology
Head-to-head clinical analysis: NORPACE CR versus PROCAINAMIDE HCL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NORPACE CR versus PROCAINAMIDE HCL.
NORPACE CR vs PROCAINAMIDE HCL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Class Ia antiarrhythmic agent; decreases myocardial excitability and conduction velocity, and prolongs refractory period by blocking sodium channels.
Class Ia antiarrhythmic agent; blocks sodium channels, decreases phase 0 slope of action potential, prolongs refractory period, and increases action potential duration.
Disopyramide controlled-release: 200 mg orally every 12 hours; maximum 400 mg/day.
For life-threatening ventricular arrhythmias, IV: Loading dose: 100 mg administered at a rate of 25-50 mg/min, may repeat every 5 minutes until arrhythmia suppressed or up to a total of 500-1000 mg. Maintenance: IV infusion 1-4 mg/min. Oral: 250-500 mg every 3-6 hours; maximum 4 g/day.
None Documented
None Documented
Terminal elimination half-life: 6-12 hours (normal renal function); prolonged to 12-20 hours in renal impairment. In coronary artery disease, half-life may be extended due to reduced clearance.
Terminal elimination half-life: 2.5-4.7 hours (3 hours typical) in normal renal function; prolonged to 11-20 hours in renal impairment; NAPA half-life 6-8 hours (prolonged in renal failure).
Renal (50-57% unchanged), hepatic metabolism (30-40%), fecal (<10%). Dose adjustment required for CrCl <40 mL/min.
Primarily renal (50-60% unchanged via glomerular filtration and tubular secretion) with 10-30% as N-acetylprocainamide (NAPA) metabolite; minor biliary/fecal (<5%).
Category C
Category A/B
Antiarrhythmic (Class Ia)
Antiarrhythmic (Class Ia)