Comparative Pharmacology
Head-to-head clinical analysis: QUINALAN versus QUINIDINE SULFATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: QUINALAN versus QUINIDINE SULFATE.
QUINALAN vs QUINIDINE SULFATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Quinidine (the active ingredient in Quinalan) is a class Ia antiarrhythmic agent that binds to and blocks voltage-gated sodium channels in cardiac myocytes, prolonging the action potential duration and effective refractory period. It also has vagolytic effects and blocks potassium channels.
Quinidine is a class Ia antiarrhythmic agent that blocks sodium channels, prolonging the effective refractory period and slowing conduction. It also inhibits potassium channels, prolonging repolarization, and has vagolytic and negative inotropic effects.
10 mg orally once daily, may increase to 20 mg after 2 weeks if needed.
300-600 mg orally every 6-8 hours; maximum 2-4 g/day. Extended-release: 300-600 mg every 8-12 hours.
None Documented
None Documented
Terminal half-life: 12 hours (range 10-14) in normal renal function; prolonged to 24-30 hours in severe renal impairment (CrCl <30 mL/min).
Terminal elimination half-life is 6-8 hours in healthy adults; prolonged to 12-18 hours in heart failure, hepatic cirrhosis, or severe renal impairment (CrCl < 10 mL/min).
Renal: 60% unchanged; Biliary/fecal: 30% as metabolites; 10% other.
Renal excretion of unchanged drug accounts for 10-20% of elimination; hepatic metabolism (hydroxylation and N-oxidation) accounts for 70-80%; about 5% excreted in feces via biliary elimination.
Category C
Category A/B
Antiarrhythmic (Class Ia)
Antiarrhythmic (Class Ia)