Comparative Pharmacology
Head-to-head clinical analysis: PACERONE versus TAMBOCOR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PACERONE versus TAMBOCOR.
PACERONE vs TAMBOCOR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Class III antiarrhythmic agent; prolongs action potential duration and refractory period by blocking potassium channels, and also exhibits class I, II, and IV effects.
Class Ic antiarrhythmic agent; blocks sodium channels, slowing conduction velocity and prolonging refractoriness in cardiac tissues.
Loading dose: 800-1600 mg/day PO in divided doses for 1-3 weeks, then 600-800 mg/day PO for 1 month; maintenance: 200-400 mg/day PO once daily. IV: 150 mg over 10 min, then 1 mg/min for 6 hours, then 0.5 mg/min.
For atrial fibrillation/flutter: 50 mg orally every 12 hours; may increase by 50 mg every 4 days up to 300 mg/day. For life-threatening ventricular arrhythmias: 100 mg orally every 12 hours; increase by 50 mg every 4 days up to 400 mg/day.
None Documented
None Documented
Biphasic: initial 3-10 days; terminal elimination half-life 40-58 days (mean ~53 days) due to extensive tissue distribution and slow release from fat. Clinical context: steady-state achieved in 2-4 months without loading dose.
Terminal elimination half-life: 12–27 hours (mean 20 hours); prolonged to 58 hours in heart failure or renal impairment (CrCl < 35 mL/min).
Primarily hepatic metabolism (CYP3A4, CYP2C8) to desethylamiodarone (active). Renal elimination of drug and metabolites: <1% of unchanged drug; ~40% of dose as metabolites. Fecal elimination: ~70% of dose as metabolites, with some parent drug.
Renal: 85% (30% unchanged, 55% as inactive metabolites); Fecal: 5%; Biliary: negligible.
Category C
Category C
Antiarrhythmic Agent
Antiarrhythmic Agent