Last reviewed · How we verify

Quinidine Gluconate (QUINIDINE SULFATE)

Eli Lilly · FDA-approved approved Small molecule Quality 65/100

Quinidine Gluconate works by blocking the M2 muscarinic acetylcholine receptor, which helps regulate heart rhythm.

Quinidine Gluconate, also known as Quinidine Sulfate, is a small molecule antiarrhythmic medication originally developed by Lilly and currently owned by the same company. It targets the muscarinic acetylcholine receptor M2 and is used to treat various conditions, including atrial fibrillation, life-threatening ventricular tachycardia, and malaria. Quinidine Gluconate has been FDA-approved since 1950 and is available as a generic medication, with 35 generic manufacturers. The medication has a half-life of 6.6 hours and a bioavailability of 75%. It is off-patent, meaning there are no active patents protecting it.

At a glance

Generic nameQUINIDINE SULFATE
SponsorEli Lilly
Drug classAntiarrhythmic
TargetMuscarinic acetylcholine receptor M2
ModalitySmall molecule
Therapeutic areaNeuroscience
PhaseFDA-approved
First approval1950

Mechanism of action

Mechanisms of action. In patients with malaria, quinidine acts primarily as an intra-erythrocytic schizonticide, with little effect upon sporozites or upon pre-erythrocytic parasites. Quinidine is gametocidal to Plasmodium vivax and P. malariae, but not to P. falciparum.In cardiac muscle and in Purkinje fibers, quinidine depresses the rapid inward depolarizing sodium current, thereby slowing phase-0 depolarization and reducing the amplitude of the action potential without affecting the resting potential. In normal Purkinje fibers, it reduces the slope of phase-4 depolarization, shifting the threshold voltage upward toward zero. The result is slowed conduction and reduced automaticity in all parts of the heart, with increase of the effective refractory period relative to the duration of the action potential in the atria, ventricles, and Purkinje tissues. Quinidine also raises the fibrillation thresholds of the atria and ventricles, and it raises the ventricular defibrillation threshold

Approved indications

Common side effects

Drug interactions

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

SourceUsed for
FDA labelMechanism, indications, dosing, boxed warnings, drug interactions
ClinicalTrials.govTrial enrolment, design, endpoints, results

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape: