Comparative Pharmacology
Head-to-head clinical analysis: BRETYLIUM TOSYLATE IN DEXTROSE 5 versus IBUTILIDE FUMARATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: BRETYLIUM TOSYLATE IN DEXTROSE 5 versus IBUTILIDE FUMARATE.
BRETYLIUM TOSYLATE IN DEXTROSE 5% vs IBUTILIDE FUMARATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Bretylium tosylate is an antiarrhythmic agent that prolongs the action potential duration and refractory period in cardiac tissue. It initially causes release of norepinephrine from sympathetic nerve endings, followed by inhibition of norepinephrine release. It has class III antiarrhythmic properties and also exhibits adrenergic blockade.
Ibutilide fumarate is a Class III antiarrhythmic agent that prolongs the atrial and ventricular refractory period by blocking the rapid component of the delayed rectifier potassium current (IKr) and also enhances the slow inward sodium current (INa), resulting in prolongation of the action potential duration and effective refractory period.
Intravenous: 5-10 mg/kg infused over 10-30 minutes, may repeat at 30-minute intervals up to a total of 30 mg/kg; maintenance: 1-2 mg/min as continuous IV infusion or 5-10 mg/kg every 6 hours by intermittent infusion. Intramuscular: 5-10 mg/kg undiluted, repeat every 1-2 hours as needed.
1 mg (10 mL of 0.1 mg/mL solution) IV infusion over 10 minutes; if arrhythmia persists after 10 minutes post-infusion, a second 1 mg dose may be administered. For patients weighing <60 kg, use 0.01 mg/kg.
None Documented
None Documented
Terminal elimination half-life is approximately 7-11 hours in patients with normal renal function, but can be prolonged to >24 hours in renal impairment or anuria, necessitating dose adjustment.
Terminal elimination half-life is 2–12 hours (mean 6 hours). In atrial fibrillation/flutter, the clinically effective half-life allowing for arrhythmia conversion is approximately 2–4 hours due to rapid redistribution.
Primarily excreted unchanged by the kidneys via glomerular filtration and tubular secretion; >70% of an administered dose recovered in urine within 24 hours; negligible biliary/fecal elimination.
Primarily hepatic metabolism; less than 10% excreted unchanged in urine. Biliary/fecal excretion accounts for approximately 20% of total clearance.
Category C
Category A/B
Antiarrhythmic (Class III)
Antiarrhythmic (Class III)