II. Indications
- Multifocal Atrial Tachycardia
-
Atrial Fibrillation Chemical Cardioversion
- Time to Cardioversion: 3-6 hours
- Conversion Rate: 38-86%
- Chronic Efficacy: 47-60%
- Life Threatening Malaria
III. Contraindications
- Complete AV Block
- Left Bundle Branch Block
IV. Mechanism
- Class Ia Antiarrhythmic (Sodium Channel Blocker, lengthens Action Potential duration)
- Similar activity as with Procainamide and Disopyramide
- Decreases the automaticity of ectopic foci
- Outside of nodes, increases heart refractory period including accessory pathways
- Decreases conduction velocity in the atria, HIs Bundle and Purkinje Fibers
- Paradoxically may increase AV Nodal conduction in rapid atrial rates due to Anticholinergic activity
- Results in QRS Widening and QTc Prolongation
V. Precautions
- Consider initial hospital-based telemetry monitoring when starting Quinidine
VI. Dosing: Arrhythmia
- Primarily oral route (IV risks Hypotension, pain with IM Injection)
- Adult
- Quinidine Gluconate extended-release 324 to 648 mg orally every 8 to 12 hours
- Quinidine Sulfate immediate-release 200 to 400 mg orally every 6 to 8 hours
- Quinidine Sulfate extended-release 300 to 600 mg orally every 8 to 12 hours
- Child
- Quinidine Sulfate immediate-release
- Start (Test Dose): 2 mg/kg up to 200 mg
- Target: 15 to 60 mg orally every 6 hours
- Quinidine Sulfate immediate-release
VII. Dosing: Life-Threatening Malaria
VIII. Pharmacokinetics
- Protein Bound: 90%
- Hepatic metabolism with renal excretion
IX. Adverse Effects
- Common
- Serious
- Proarrhythmic
- Torsades de Pointes (Quinidine prolongs QTc)
- Ventricular increased response to Atrial Tachycardia
- Thrombotic Thrombocytopenic Purpura
- Mortality is increased when used in non-lethal Arrhythmia and comorbid CAD, CHF
- Cinchonism
- Proarrhythmic
X. Drug Interactions
- Quinidine increased metabolism with decreased effects
- Quinidine potentiates other drugs
- Digoxin
- Vasodilators (increased risk of Hypotension)
- Warfarin
XI. Safety
- Pregnancy Category C
- Considered safe in Lactation
XII. Resources
- Quinidine Sulfate Tablet (DailyMed)
- Quinidine Gluconate Extended Release (DailyMed)
XIII. References
- Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 74-5
- Hamilton (2020) Tarascon Pocket Pharmacopoeia
Images: Related links to external sites (from Bing)
Related Studies
| Definition (NCI) | An alkaloid extracted from the bark of the Cinchona tree with class 1A antiarrhythmic and antimalarial effects. Quinidine stabilizes the neuronal membrane by binding to and inhibiting voltage-gated sodium channels, thereby inhibiting the sodium influx required for the initiation and conduction of impulses resulting in an increase of the threshold for excitation and decreased depolarization during phase 0 of the action potential. In addition, the effective refractory period (ERP), action potential duration (APD), and ERP/APD ratios are increased, resulting in decreased conduction velocity of nerve impulses. Quinidine exerts its antimalarial activity by acting primarily as an intra-erythrocytic schizonticide through association with the heme polymer (hemazoin) in the acidic food vacuole of the parasite thereby preventing further polymerization by heme polymerase enzyme. This results in accumulation of toxic heme and death of the parasite. |
| Definition (MSH) | An optical isomer of quinine, extracted from the bark of the CHINCHONA tree and similar plant species. This alkaloid dampens the excitability of cardiac and skeletal muscles by blocking sodium and potassium currents across cellular membranes. It prolongs cellular ACTION POTENTIALS, and decreases automaticity. Quinidine also blocks muscarinic and alpha-adrenergic neurotransmission. |
| Definition (CSP) | D isomer of quinine; sometimes used as an antimalarial in patients who cannot tolerate quinine. |
| Definition (PDQ) | An alkaloid extracted from the bark of the Cinchona tree with class 1A antiarrhythmic and antimalarial effects. Quinidine stabilizes the neuronal membrane by binding to and inhibiting voltage-gated sodium channels, thereby inhibiting the sodium influx required for the initiation and conduction of impulses resulting in an increase of the threshold for excitation and decreased depolarization during phase 0 of the action potential. In addition, the effective refractory period (ERP), action potential duration (APD), and ERP/APD ratios are increased, resulting in decreased conduction velocity of nerve impulses. Quinidine exerts its antimalarial activity by acting primarily as an intra-erythrocytic schizonticide through association with the heme polymer (hemazoin) in the acidic food vacuole of the parasite thereby preventing further polymerization by heme polymerase enzyme. This results in accumulation of toxic heme and death of the parasite. Check for "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=39022&idtype=1" active clinical trials or "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=39022&idtype=1&closed=1" closed clinical trials using this agent. ("http://nciterms.nci.nih.gov:80/NCIBrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&code=C793" NCI Thesaurus) |
| Concepts | Pharmacologic Substance (T121) , Organic Chemical (T109) |
| MSH | D011802 |
| SnomedCT | 31306009, 372697008 |
| LNC | LP16271-6, MTHU005039 |
| English | Chinidin, Quinidine, Cinchonan-9-ol, 6'-methoxy-, (9S)-, quinidine (medication), Quinidine [Chemical/Ingredient], quiNIDine, quinidine, QUINIDINE, Quinidine (product), Quinidine (substance) |
| Swedish | Kinidin |
| Czech | chinidin |
| Finnish | Kinidiini |
| Russian | KHINIDIN, ХИНИДИН |
| Japanese | 硫酸キニジン, キニジン |
| Croatian | KINIDIN |
| Polish | Chinidyna |
| Spanish | quinidina (producto), quinidina (sustancia), quinidina, Quinidina |
| French | Quinidine |
| German | Chinidin |
| Italian | Chinidina |
| Portuguese | Quinidina |
Ontology: Quinaglute (C1097294)
| Concepts | Pharmacologic Substance (T121) , Organic Chemical (T109) |
| MSH | C016713 |
| English | Quinaglute, quinaglute, Berlex brand of quinidine gluconate |
