Comparative Pharmacology
Head-to-head clinical analysis: BRETYLIUM TOSYLATE versus BRETYLOL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: BRETYLIUM TOSYLATE versus BRETYLOL.
BRETYLIUM TOSYLATE vs BRETYLOL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Bretylium tosylate is a class III antiarrhythmic agent that prolongs the action potential duration and refractory period by blocking potassium channels. It also initially causes norepinephrine release, leading to transient hypertension and increased contractility, followed by adrenergic neuron blockade, resulting in hypotension and reduced contractility.
Bretylium tosylate is an adrenergic neuron blocking agent that inhibits norepinephrine release and enhances its reuptake, resulting in postganglionic sympathetic blockade. It also has direct antiarrhythmic effects by increasing the ventricular fibrillation threshold.
For ventricular tachycardia/fibrillation: 5-10 mg/kg IV bolus over 1-2 minutes, may repeat every 15-30 minutes up to 30 mg/kg total. Maintenance: 5-10 mg/kg IV every 6 hours or 0.5-2 mg/min continuous infusion. Intramuscular: 5-10 mg/kg undiluted, may repeat every 1-2 hours.
Intravenous: 5-10 mg/kg over 10 minutes, then 5-10 mg/kg every 6-8 hours as needed for arrhythmias. Intramuscular: 5-10 mg/kg, may repeat every 6-8 hours.
None Documented
None Documented
5-10 hours; prolonged in renal impairment (up to 30 hours)
Terminal elimination half-life is 7-11 hours in normal renal function; prolonged in renal impairment (up to 30 hours)
Renal: ~80% unchanged; biliary/fecal: <1%
Primarily renal excretion of unchanged drug (80-90%); minor biliary/fecal elimination (10-20%)
Category C
Category C
Antiarrhythmic (Class III)
Antiarrhythmic (Class III)