Comparative Pharmacology
Head-to-head clinical analysis: BRETYLIUM TOSYLATE IN DEXTROSE 5 versus DOFETILIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: BRETYLIUM TOSYLATE IN DEXTROSE 5 versus DOFETILIDE.
BRETYLIUM TOSYLATE IN DEXTROSE 5% vs DOFETILIDE
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.
Selectively blocks the rapid component of the delayed rectifier potassium current (Ikr) in cardiac myocytes, prolonging repolarization and the 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.
250-500 mcg orally twice daily, based on creatinine clearance and QTc response.
None Documented
None Documented
Clinical Note
moderateDofetilide + Levofloxacin
"Dofetilide may increase the QTc-prolonging activities of Levofloxacin."
Clinical Note
moderateDofetilide + Norfloxacin
"Dofetilide may increase the QTc-prolonging activities of Norfloxacin."
Clinical Note
moderateDofetilide + Gemifloxacin
"Dofetilide may increase the QTc-prolonging activities of Gemifloxacin."
Clinical Note
moderateDofetilide + Torasemide
"Dofetilide may increase the QTc-prolonging activities of Torasemide."
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: 10 hours (range 7–13 hours) in patients with normal renal function; prolonged in renal impairment, up to 20 hours in moderate impairment and >30 hours in severe impairment.
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.
Renal: 80% unchanged; biliary/fecal: 20% as metabolites and unchanged drug.
Category C
Category C
Antiarrhythmic (Class III)
Antiarrhythmic (Class III)