Quinidine
- Atc Codes:C01BA01
- CAS Codes:56-54-2#7054-25-3#6591-63-5#50-54-4
- PHARMGKB ID:56-54-2#7054-25-3#6591-63-5#50-54-4
Table of contents
- Brand Names
- Drug Combinations
- Chemistry
- Pharmacologic Category
- Mechanism of Action
- Therapeutic Use
- Pregnancy and Lactation Implications
- Contraindications
- Warnings and Precautions
- Adverse Reactions
- Caution and personalized dose adjustment in patients with the following genotypes
- Other genes that may be involved
- Substrate of
- Inhibits
- Drug Interactions
- Nutrition/Nutraceutical Interactions
- Dosage
- Pharmacokinetics and Pharmacodynamics
- Special Considerations
Brand Names
Europe
Bulgaria: Chinidin; Germany: Chinidin; Greece: Kinidin; Hungary: Chinidin; Italy: Chinid S; Netherlands: Kinidinesulfaat; Poland: Chinidinum, Kinidin; Romania: Chinidina.
North America
Canada: Apo-Quin-G, Quinidine.
Latin America
Argentina: Quinidina; Brazil: Quinicardine, Quinidine.
Asia
Japan: Quinidine.
Drug combinations
Quinidine and Dextromethorphan
Quinidine and Verapamil
Chemistry
Quinidine: C~20~H~24~N~2~O~2~. Mw: 324.42. (8R,9S)-6′-Methoxycinchonan-9-ol. CAS-56-54-2.
Quinidine Gluconate: C~20~H~24~N~2~O~2~ C~6~H~12~O~7~. Mw: 520.57. Cinchonan-9-ol, 6′-methoxy-, (9S)-, mono-D-gluconate. CAS-7054-25-3.
Quinidine Sulfate: (C~20~H~24~N~2~O~2~)~2~ H~2~SO~4~ 2H~2~O. Mw: 782.94. Cinchonan-9-ol, 6′-methoxy-, (9S)-, sulfate (2:1), dihydrate. CAS-6591-63-5; CAS-50-54-4 (anhydrous).
Pharmacologic Category
Antiprotozoals; Antimalarials. Class Ia Antiarrhythmics. (ATC-Code: C01BA01).
Mechanism of action
Depresses phase 0 of action potential. Decreases myocardial excitability and conduction velocity, and myocardial contractility by decreasing sodium influx during depolarization and potassium efflux in repolarization. Also reduces calcium transport across cell membrane. Decreases conduction velocity in atria, ventricles, and His-Purkinje system, and may decrease or cause no change in conduction velocity through AV node. May suppress atrial fibrillation or flutter. May produce sinus tachycardia via its anticholinergic effects. Has direct negative inotropic effect, but therapeutic plasma concentrations of drug do not usually depress contractility in normal heart. May reduce peripheral resistance and blood pressure by blockade of α-adrenergic receptors and by effects on myocardial contractility. Acts principally as intraerythrocytic schizonticide (has little effect on sporozoites or pre-erythrocytic parasites). Gametocidal against Plasmodium vivax and P. malariae, but not P. falciparum.
Therapeutic use
Prophylaxis after cardioversion of atrial fibrillation and/or flutter to maintain normal sinus rhythm. Prevent recurrence of paroxysmal supraventricular tachycardia, paroxysmal AV junctional rhythm, paroxysmal ventricular tachycardia, paroxysmal atrial fibrillation, and atrial or ventricular premature contractions. Has activity against Plasmodium falciparum malaria.
Pregnancy and lactiation implications
Unknown whether quinidine can cause fetal harm when administered to pregnant women. Use during pregnancy only when clearly needed. Drug exhibits oxytocic properties. Since quinidine is distributed into milk, drug should be used with extreme caution in nursing women.
Unlabeled use
Contraindications
Hypersensitivity to quinidine or any component of the formulation. Thrombocytopenia, thrombocytopenic purpura. Myasthenia gravis. Heart block greater than first degree, idioventricular conduction delays (except in patients with functioning artificial pacemaker). Those adversely affected by anticholinergic activity. Concurrent use of quinolone antibiotics which prolong QT interval, cisapride, amprenavir, or ritonavir.
Warnings and precautions
Associated with severe hepatotoxic reactions, including granulomatous hepatitis. Hypersensitivity reactions may occur. Watch for proarrhythmic effects. Antiarrhythmic drugs have not been shown to enhance survival in non-life-threatening ventricular arrhythmias and may increase mortality; risk greatest with structural heart disease. Quinidine may increase mortality in treatment of atrial fibrillation/flutter. May increase ventricular response rate in atrial fibrillation or flutter. Use with caution in risk for heart block (can unmask sick sinus syndrome), and in heart failure. Caution with concurrent use of other antiarrhythmics. May cause digoxin-induced toxicity. Electrolyte disturbances should be corrected, especially hypokalemia or hypomagnesemia. Hemolysis may occur in G6PD deficiency. Use with caution in hepatic impairment.