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Details

Stereochemistry ABSOLUTE
Molecular Formula C20H24N2O2.ClH
Molecular Weight 360.878
Optical Activity UNSPECIFIED
Defined Stereocenters 5 / 5
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of QUINIDINE HYDROCHLORIDE

SMILES

Cl.[H][C@@]1(C[C@@H]2CC[N@]1C[C@@H]2C=C)[C@@H](O)C3=C4C=C(OC)C=CC4=NC=C3

InChI

InChIKey=LBSFSRMTJJPTCW-VJAUXQICSA-N
InChI=1S/C20H24N2O2.ClH/c1-3-13-12-22-9-7-14(13)10-19(22)20(23)16-6-8-21-18-5-4-15(24-2)11-17(16)18;/h3-6,8,11,13-14,19-20,23H,1,7,9-10,12H2,2H3;1H/t13-,14-,19+,20-;/m0./s1

HIDE SMILES / InChI

Molecular Formula ClH
Molecular Weight 36.461
Charge 0
Count
Stereochemistry ACHIRAL
Additional Stereochemistry No
Defined Stereocenters 0 / 0
E/Z Centers 0
Optical Activity NONE

Molecular Formula C20H24N2O2
Molecular Weight 324.4168
Charge 0
Count
Stereochemistry ABSOLUTE
Additional Stereochemistry No
Defined Stereocenters 4 / 4
E/Z Centers 0
Optical Activity UNSPECIFIED

Description
Curator's Comment: description was created based on several sources, including https://www.ncbi.nlm.nih.gov/pubmed/17506538 | https://www.ncbi.nlm.nih.gov/pubmed/22761000 | https://www.ncbi.nlm.nih.gov/pubmed/22512909 | https://www.ncbi.nlm.nih.gov/pubmed/21832259

Quinidine is a pharmaceutical agent that acts as a class I antiarrhythmic agent (Ia) in the heart. It is a stereoisomer of quinine, originally derived from the bark of the cinchona tree. The drug causes increased action potential duration, as well as a prolonged QT interval. Like all other class I antiarrhythmic agents, quinidine primarily works by blocking the fast inward sodium current (INa). Quinidine's effect on INa is known as a 'use-dependent block'. This means at higher heart rates, the block increases, while at lower heart rates, the block decreases. The effect of blocking the fast inward sodium current causes the phase 0 depolarization of the cardiac action potential to decrease (decreased Vmax). Quinidine also blocks the slowly inactivating, tetrodotoxin-sensitive Na current, the slow inward calcium current (ICA), the rapid (IKr) and slow (IKs) components of the delayed potassium rectifier current, the inward potassium rectifier current (IKI), the ATP-sensitive potassium channel (IKATP) and Ito. Quinidine is also an inhibitor of the cytochrome P450 enzyme 2D6 and can lead to increased blood levels of lidocaine, beta blockers, opioids, and some antidepressants. Quinidine also inhibits the transport protein P-glycoprotein and so can cause some peripherally acting drugs such as loperamide to have central nervous system side effects, such as respiratory depression if the two drugs are coadministered. Quinidine can cause thrombocytopenia, granulomatous hepatitis, myasthenia gravis, and torsades de pointes, so is not used much today. Torsades can occur after the first dose. Quinidine-induced thrombocytopenia (low platelet count) is mediated by the immune system and may lead to thrombocytic purpura. A combination of dextromethorphan and quinidine has been shown to alleviate symptoms of easy laughing and crying (pseudobulbar affect) in patients with amyotrophic lateral sclerosis and multiple sclerosis. This drug is marketed as Nuedexta in the United States. Intravenous quinidine is also indicated for the treatment of Plasmodium falciparum malaria. However, quinidine is not considered the first-line therapy for P. falciparum. The recommended treatments for P. falciparum malaria, according to the Toronto Notes 2008, are a combination of either quinine and doxycycline or atovaquone and proguanil (Malarone). The drug is also effective for the treatment of atrial fibrillation in horses.

Approval Year

TargetsConditions

Conditions

ConditionModalityTargetsHighest PhaseProduct
Primary
QUINIDINE GLUCONATE

Approved Use

Conversion of atrial fibrillation/flutter In patients with symptomatic atrial fibrillation/flutter whose symptoms are not adequately controlled by measures that reduce the rate of ventricular response, quinidine sulfate is indicated as a means of restoring normal sinus rhythm. If this use of quinidine sulfate does not restore sinus rhythm within a reasonable time (see ), then quinidine sulfate should be discontinued. DOSAGE AND ADMINISTRATION Reduction of frequency of relapse into atrial fibrillation/flutter Chronic therapy with quinidine sulfate is indicated for some patients at high risk of symptomatic atrial fibrillation/flutter, generally patients who have had previous episodes of atrial fibrillation/flutter that were so frequent and poorly tolerated as to outweigh, in the judgment of the physician and the patient, the risks of prophylactic therapy with quinidine sulfate. The increased risk of death should specifically be considered. Quinidine sulfate should be used only after alternative measures ( use of other drugs to control the ventricular rate) have been found to be inadequate. e.g., In patients with histories of frequent symptomatic episodes of atrial fibrillation/flutter, the goal of therapy should be an increase in the average time between episodes. In most patients, the tachyarrhythmia during therapy, and a single recurrence should not be interpreted as therapeutic failure. will recur Suppression of ventricular arrhythmias Quinidine sulfate is also indicated for the suppression of recurrent documented ventricular arrhythmias, such as sustained ventricular tachycardia, that in the judgment of the physician are life-threatening. Because of the proarrhythmic effects of quinidine, its use with ventricular arrhythmias of lesser severity is generally not recommended, and treatment of patients with asymptomatic ventricular premature contractions should be avoided. Where possible, therapy should be guided by the results of programmed electrical stimulation and/or Holter monitoring with exercise. Antiarrhythmic drugs (including quinidine sulfate) have not been shown to enhance survival in patients with ventricular arrhythmias. Treatment of malaria Quinidine sulfate is also indicated in the treatment of life-threatening malaria. Plasmodium falciparum

Launch Date

1950
Primary
QUINIDINE GLUCONATE

Approved Use

Conversion of atrial fibrillation/flutter In patients with symptomatic atrial fibrillation/flutter whose symptoms are not adequately controlled by measures that reduce the rate of ventricular response, quinidine sulfate is indicated as a means of restoring normal sinus rhythm. If this use of quinidine sulfate does not restore sinus rhythm within a reasonable time (see ), then quinidine sulfate should be discontinued. DOSAGE AND ADMINISTRATION Reduction of frequency of relapse into atrial fibrillation/flutter Chronic therapy with quinidine sulfate is indicated for some patients at high risk of symptomatic atrial fibrillation/flutter, generally patients who have had previous episodes of atrial fibrillation/flutter that were so frequent and poorly tolerated as to outweigh, in the judgment of the physician and the patient, the risks of prophylactic therapy with quinidine sulfate. The increased risk of death should specifically be considered. Quinidine sulfate should be used only after alternative measures ( use of other drugs to control the ventricular rate) have been found to be inadequate. e.g., In patients with histories of frequent symptomatic episodes of atrial fibrillation/flutter, the goal of therapy should be an increase in the average time between episodes. In most patients, the tachyarrhythmia during therapy, and a single recurrence should not be interpreted as therapeutic failure. will recur Suppression of ventricular arrhythmias Quinidine sulfate is also indicated for the suppression of recurrent documented ventricular arrhythmias, such as sustained ventricular tachycardia, that in the judgment of the physician are life-threatening. Because of the proarrhythmic effects of quinidine, its use with ventricular arrhythmias of lesser severity is generally not recommended, and treatment of patients with asymptomatic ventricular premature contractions should be avoided. Where possible, therapy should be guided by the results of programmed electrical stimulation and/or Holter monitoring with exercise. Antiarrhythmic drugs (including quinidine sulfate) have not been shown to enhance survival in patients with ventricular arrhythmias. Treatment of malaria Quinidine sulfate is also indicated in the treatment of life-threatening malaria. Plasmodium falciparum

Launch Date

1950
Primary
QUINIDINE GLUCONATE

Approved Use

Conversion of atrial fibrillation/flutter In patients with symptomatic atrial fibrillation/flutter whose symptoms are not adequately controlled by measures that reduce the rate of ventricular response, quinidine sulfate is indicated as a means of restoring normal sinus rhythm. If this use of quinidine sulfate does not restore sinus rhythm within a reasonable time (see ), then quinidine sulfate should be discontinued. DOSAGE AND ADMINISTRATION Reduction of frequency of relapse into atrial fibrillation/flutter Chronic therapy with quinidine sulfate is indicated for some patients at high risk of symptomatic atrial fibrillation/flutter, generally patients who have had previous episodes of atrial fibrillation/flutter that were so frequent and poorly tolerated as to outweigh, in the judgment of the physician and the patient, the risks of prophylactic therapy with quinidine sulfate. The increased risk of death should specifically be considered. Quinidine sulfate should be used only after alternative measures ( use of other drugs to control the ventricular rate) have been found to be inadequate. e.g., In patients with histories of frequent symptomatic episodes of atrial fibrillation/flutter, the goal of therapy should be an increase in the average time between episodes. In most patients, the tachyarrhythmia during therapy, and a single recurrence should not be interpreted as therapeutic failure. will recur Suppression of ventricular arrhythmias Quinidine sulfate is also indicated for the suppression of recurrent documented ventricular arrhythmias, such as sustained ventricular tachycardia, that in the judgment of the physician are life-threatening. Because of the proarrhythmic effects of quinidine, its use with ventricular arrhythmias of lesser severity is generally not recommended, and treatment of patients with asymptomatic ventricular premature contractions should be avoided. Where possible, therapy should be guided by the results of programmed electrical stimulation and/or Holter monitoring with exercise. Antiarrhythmic drugs (including quinidine sulfate) have not been shown to enhance survival in patients with ventricular arrhythmias. Treatment of malaria Quinidine sulfate is also indicated in the treatment of life-threatening malaria. Plasmodium falciparum

Launch Date

1950
Cmax

Cmax

ValueDoseCo-administeredAnalytePopulation
3.4 μg/mL
3.74 mg/kg single, oral
dose: 3.74 mg/kg
route of administration: Oral
experiment type: SINGLE
co-administered:
QUINIDINE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: MALE
food status: UNKNOWN
AUC

AUC

ValueDoseCo-administeredAnalytePopulation
12.8 μg × h/mL
3.74 mg/kg single, oral
dose: 3.74 mg/kg
route of administration: Oral
experiment type: SINGLE
co-administered:
QUINIDINE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: MALE
food status: UNKNOWN
T1/2

T1/2

ValueDoseCo-administeredAnalytePopulation
5.8 h
3.74 mg/kg single, oral
dose: 3.74 mg/kg
route of administration: Oral
experiment type: SINGLE
co-administered:
QUINIDINE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: MALE
food status: UNKNOWN
8 h
202 mg single, oral
dose: 202 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
QUINIDINE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
Funbound

Funbound

ValueDoseCo-administeredAnalytePopulation
12%
202 mg single, oral
dose: 202 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
QUINIDINE plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: UNKNOWN
food status: UNKNOWN
Doses

Doses

DosePopulationAdverse events​
200 mg 4 times / day multiple, oral
Dose: 200 mg, 4 times / day
Route: oral
Route: multiple
Dose: 200 mg, 4 times / day
Sources:
unhealthy, 47 years
n = 1
Health Status: unhealthy
Age Group: 47 years
Sex: M
Population Size: 1
Sources:
Disc. AE: Hepatotoxicity...
AEs leading to
discontinuation/dose reduction:
Hepatotoxicity
Sources:
324 mg 5 times / day multiple, oral
Dose: 324 mg, 5 times / day
Route: oral
Route: multiple
Dose: 324 mg, 5 times / day
Sources:
unhealthy, 56 yeras
n = 1
Health Status: unhealthy
Age Group: 56 yeras
Sex: F
Population Size: 1
Sources:
Disc. AE: Myalgia...
AEs leading to
discontinuation/dose reduction:
Myalgia (severe, 1 patient)
Sources:
4 g single, oral
Overdose
Dose: 4 g
Route: oral
Route: single
Dose: 4 g
Sources:
healthy, 57 years
n = 1
Health Status: healthy
Age Group: 57 years
Sex: F
Population Size: 1
Sources:
Other AEs: Grand mal convulsion, Cardiotoxicity...
Other AEs:
Grand mal convulsion (1 patient)
Cardiotoxicity (1 patient)
Sources:
324 mg 3 times / day multiple, oral
Dose: 324 mg, 3 times / day
Route: oral
Route: multiple
Dose: 324 mg, 3 times / day
Co-administed with::
digoxin
levothyroxine sodium
crystalline warfarin sodium
Sources:
unhealthy, 79 years
n = 1
Health Status: unhealthy
Age Group: 79 years
Sex: F
Population Size: 1
Sources:
Disc. AE: Drug-induced lupus erythematosus...
AEs leading to
discontinuation/dose reduction:
Drug-induced lupus erythematosus (1 patient)
Sources:
370 mg 6 times / day multiple, oral
Highest studied dose
Dose: 370 mg, 6 times / day
Route: oral
Route: multiple
Dose: 370 mg, 6 times / day
Sources:
healthy, > 23 years
n = 1
Health Status: healthy
Age Group: > 23 years
Sex: M
Population Size: 1
Sources:
1650 mg single, intravenous
Dose: 1650 mg
Route: intravenous
Route: single
Dose: 1650 mg
Sources:
healthy, > 23 years
n = 1
Health Status: healthy
Age Group: > 23 years
Sex: M
Population Size: 1
Sources:
AEs

AEs

AESignificanceDosePopulation
Hepatotoxicity Disc. AE
200 mg 4 times / day multiple, oral
Dose: 200 mg, 4 times / day
Route: oral
Route: multiple
Dose: 200 mg, 4 times / day
Sources:
unhealthy, 47 years
n = 1
Health Status: unhealthy
Age Group: 47 years
Sex: M
Population Size: 1
Sources:
Myalgia severe, 1 patient
Disc. AE
324 mg 5 times / day multiple, oral
Dose: 324 mg, 5 times / day
Route: oral
Route: multiple
Dose: 324 mg, 5 times / day
Sources:
unhealthy, 56 yeras
n = 1
Health Status: unhealthy
Age Group: 56 yeras
Sex: F
Population Size: 1
Sources:
Cardiotoxicity 1 patient
4 g single, oral
Overdose
Dose: 4 g
Route: oral
Route: single
Dose: 4 g
Sources:
healthy, 57 years
n = 1
Health Status: healthy
Age Group: 57 years
Sex: F
Population Size: 1
Sources:
Grand mal convulsion 1 patient
4 g single, oral
Overdose
Dose: 4 g
Route: oral
Route: single
Dose: 4 g
Sources:
healthy, 57 years
n = 1
Health Status: healthy
Age Group: 57 years
Sex: F
Population Size: 1
Sources:
Drug-induced lupus erythematosus 1 patient
Disc. AE
324 mg 3 times / day multiple, oral
Dose: 324 mg, 3 times / day
Route: oral
Route: multiple
Dose: 324 mg, 3 times / day
Co-administed with::
digoxin
levothyroxine sodium
crystalline warfarin sodium
Sources:
unhealthy, 79 years
n = 1
Health Status: unhealthy
Age Group: 79 years
Sex: F
Population Size: 1
Sources:
OverviewDrug as perpetrator​

Drug as perpetrator​

TargetModalityActivityMetaboliteClinical evidence
no
no
no
no
no
no
no
no
no
no
no
yes [IC50 0.051 uM]
likely (co-administration study)
Comment: Caution must be exercixed whenever quinidine is prescribed together with drugs metabolized by CYP2C6.
Page: 5.0
yes [IC50 18.3 uM]
yes [IC50 5.7 uM]
yes [IC50 8.7 uM]
yes [IC50 9.52 uM]
yes [Ki 23.1 uM]
yes [Ki 29.2 uM]
Drug as victim

Drug as victim

TargetModalityActivityMetaboliteClinical evidence
minor
no
no
yes
yes
yes
yes
likely (co-administration study)
Comment: coadministration of quinidine causes variable slowing of the metabolism of nifedipine. Interactions with other dihydropyridine calcium channel blockers have not been reported, but these agents (including felodipine, nicardipine, and nimodipine) are all dependent upon P450IIIA4 for metabolism, so similar interactions with quinidine should be anticipated
Page: 2.0
Tox targets
Sourcing

Sourcing

Vendor/AggregatorIDURL
PubMed

PubMed

TitleDatePubMed
Quinidine-induced lupus nephritis.
1976 May 3
Images in cardiovascular medicine. Labile repolarization from "cell to bedside".
2000 Aug 15
Metabolism of 3-methylindole by porcine liver microsomes: responsible cytochrome P450 enzymes.
2000 Jun
TASK-3, a new member of the tandem pore K(+) channel family.
2000 Mar 31
Drug interaction studies with esomeprazole, the (S)-isomer of omeprazole.
2001
Pharmacokinetic interactions of antimalarial agents.
2001
Cardiovascular effects of verapamil and quinidine at normal and elevated ambient pressure.
2001 Apr
Factors influencing the prediction of steady state concentrations of digoxin.
2001 Apr
Angiotensin II type I receptor modulates intracellular free Mg2+ in renally derived cells via Na+-dependent Ca2+-independent mechanisms.
2001 Apr 27
Study of tea polyphenol as a reversal agent for carcinoma cell lines' multidrug resistance (study of TP as a MDR reversal agent).
2001 Aug
Escitalopram (S-citalopram) and its metabolites in vitro: cytochromes mediating biotransformation, inhibitory effects, and comparison to R-citalopram.
2001 Aug
Characterization of a novel cationic drug transporter in human retinal pigment epithelial cells.
2001 Feb
Modulation of P450 CYP3A4-dependent metabolism by P-glycoprotein: implications for P450 phenotyping.
2001 Feb
Transport of [3H]MPP+ in an immortalized rat brain microvessel endothelial cell line (RBE 4).
2001 Jan
A novel zidovudine uptake system in microglia.
2001 Jan
Evaluation of a vincristine resistant Caco-2 cell line for use in a calcein AM extrusion screening assay for P-glycoprotein interaction.
2001 Jan
A high-performance liquid chromatographic assay for the determination of desbutylhalofantrine enantiomers in rat plasma.
2001 Jan-Apr
Effect of mdr1a P-glycoprotein gene disruption, gender, and substrate concentration on brain uptake of selected compounds.
2001 Jul
Synchronized neural activity in the Drosophila memory centers and its modulation by amnesiac.
2001 Jun
Characterization of (+/-)-bufuralol hydroxylation activities in liver microsomes of Japanese and Caucasian subjects genotyped for CYP2D6.
2001 Mar
Metabolism of amiodarone (Part III): identification of rabbit cytochrome P450 isoforms involved in the hydroxylation of mono-N-desethylamiodarone.
2001 May
Oral quinine pharmacokinetics and dietary salt intake.
2001 May
Inhibition of cytochrome P4502D6 activity with paroxetine normalizes the ultrarapid metabolizer phenotype as measured by nortriptyline pharmacokinetics and the debrisoquin test.
2001 Oct
GAT2/BGT-1 as a system responsible for the transport of gamma-aminobutyric acid at the mouse blood-brain barrier.
2001 Oct
In vitro effect of alkaloids on bloodstream forms of Trypanosoma brucei and T. congolense.
2001 Oct
Functional expression of P-glycoprotein in rat brain microglia.
2001 Oct
Alkaline phosphatase from rat liver and kidney is differentially modulated.
2001 Sep
Development of stereoselective nonaqueous capillary electrophoresis system for the resolution of cationic and amphoteric analytes.
2001 Sep
Quinidine induced electrocardiographic normalization in two patients with Brugada syndrome.
2001 Sep
Pharmacologic conversion of atrial fibrillation: a systematic review of available evidence.
2001 Sep-Oct
Patents

Sample Use Guides

In Vivo Use Guide
Tablet (sulfate):100 to 600 mg/dose orally every 4 to 6 hours; begin at 200 mg/dose and titrate to desired effect (maximum daily dose: 3 to 4 g). Extended Release: 324 to 648 mg (gluconate) orally every 8 to 12 hours or 300 to 600 mg (sulfate) orally every 8 to 12 hours. IV: 800 mg of quinidine gluconate diluted to 50 mL and given at a rate not to exceed 1 mL/min.
Route of Administration: Other
Rat brain pericytes were plated onto the backside of 12-well Transwell filters (pore size: 0.4 μm; 1.5 × 104 cells/filter). The next day, endothelial cells were plated onto the upper surface of the filters. After reaching confluency, the endothelial monolayer was supplied with 550 nM hydrocortisone, 250 μM CPT-cAMP, and 17.5 μM RO-201724 and placed into dishes containing glial cultures for 24 h. Transwell filters containing endothelial cells and pericytes were removed from the plates containing the glial culture. Filters were washed with Ringer-HEPES solution (pH 7.4). Quinidine or digoxin was applied at final concentrations of 0.1 μM and 10 μM, respectively. Radiolabeled quinidine and digoxin as tracers were also added to the radioactive concentration of 1 μCi/mL. The inhibitors were added together with the test compound at final concentrations of 1 μM (LY- 335979 and PSC-833) or 100 μM (quinidine). Samples were taken from the basolateral or apical side, respectively, at 15, 30, and 60 min, and radioactivity was measured using a liquid scintillation counter
Substance Class Chemical
Created
by admin
on Fri Dec 15 15:01:39 GMT 2023
Edited
by admin
on Fri Dec 15 15:01:39 GMT 2023
Record UNII
S4P5V5597B
Record Status Validated (UNII)
Record Version
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Name Type Language
QUINIDINE HYDROCHLORIDE
WHO-DD  
Common Name English
Quinidine hydrochloride [WHO-DD]
Common Name English
CINCHONAN-9-OL, 6'-METHOXY-, HYDROCHLORIDE (1:1), (9S)-
Common Name English
Code System Code Type Description
PUBCHEM
11639099
Created by admin on Fri Dec 15 15:01:40 GMT 2023 , Edited by admin on Fri Dec 15 15:01:40 GMT 2023
PRIMARY
EPA CompTox
DTXSID00937246
Created by admin on Fri Dec 15 15:01:40 GMT 2023 , Edited by admin on Fri Dec 15 15:01:40 GMT 2023
PRIMARY
EVMPD
SUB15079MIG
Created by admin on Fri Dec 15 15:01:40 GMT 2023 , Edited by admin on Fri Dec 15 15:01:40 GMT 2023
PRIMARY
ECHA (EC/EINECS)
216-792-8
Created by admin on Fri Dec 15 15:01:40 GMT 2023 , Edited by admin on Fri Dec 15 15:01:40 GMT 2023
PRIMARY
CAS
1668-99-1
Created by admin on Fri Dec 15 15:01:40 GMT 2023 , Edited by admin on Fri Dec 15 15:01:40 GMT 2023
PRIMARY
SMS_ID
100000090026
Created by admin on Fri Dec 15 15:01:40 GMT 2023 , Edited by admin on Fri Dec 15 15:01:40 GMT 2023
PRIMARY
FDA UNII
S4P5V5597B
Created by admin on Fri Dec 15 15:01:40 GMT 2023 , Edited by admin on Fri Dec 15 15:01:40 GMT 2023
PRIMARY
DRUG BANK
DBSALT002206
Created by admin on Fri Dec 15 15:01:40 GMT 2023 , Edited by admin on Fri Dec 15 15:01:40 GMT 2023
PRIMARY
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