Quinidine

DEA Class; Rx

Common Brand Names; Quinaglute, Quinidex, quinidine gluconate

  • Antidysrhythmics, Ia; 
  • Antimalarials

Parenteral and oral class IA antiarrhythmic; used for atrial arrhythmias and ventricular tachycardia; also used for severe malaria.

Indicated for conversion to and/or maintenance of sinus rhythm in patients with atrial fibrillation, atrial flutter, or ventricular tachycardia; or for the treatment of paroxysmal supraventricular tachycardia (PSVT); or for paroxysmal supraventricular tachycardia (PSVT) prophylaxis in patients with reentrant tachycardias, including patients with Wolff-Parkinson-White (WPW) syndrome.

For the treatment of persistent singultus (hiccups).

Hypersensitivity to quinidine or cinchona alkaloids

Myasthenia gravis, thrombocytopenia or developed thrombocytopenic purpura during prior therapy with quinidine or quinine

Heart block >1st degree

Idioventricular conduction delays, including patients in complete atrioventricular block (except when artificial pacemaker present)

Patients adversely affected by anticholinergic activity

Drugs or conditions that prolong QT interval

  • Diarrhea (35%)
  • Stomach cramping (22%)
  • Lightheadedness (15%)
  • QTc prolongation (modest prolongation common; excessive prolongation rare & indicates toxicity) (>10%)
  • Anorexia (>10%)
  • Bitter taste (>10%)
  • Diarrhea (>10%)
  • Upper GI distress (>10%)
  • Nausea (>10%)
  • Vomiting (>10%)
  • Syncope (1-8%)
  • Palpitation (7%), new or worsened arrhythmias (proarrhythmic effect),
  • Headache (7%)
  • Fatigue (7%)
  • Angina (6%)
  • Rash (5%)
  • Weakness (5%)
  • Sleep disturbance (3%)
  • Nervousness (2%)
  • Tremor (2%)
  • Incoordination (1%)
  • Blurred vision
  • Tinnitus
  • Wheezing
  • Hypotension
  • Hepatotoxicity
  • Arthralgia
  • Diplopia
  • Night blindness
  • Hypersensitivity reactions (eg, fever, hemolytic/aplastic anemia, respiratory arrest, agranulocytosis)
  • Systemic lupus erythematosus may occur if taking quinidine for prolonged period of time

Use caution in acute rheumatic fever, acute thyrotoxicosis, CHF, subacute bacterial endocarditis, syncope

Electrolyte imbalances due to severe N/V, diarrhea, eating disorders may occur; use caution

IV administration requires continuous cardiac & blood pressure monitoring

Dose should be adjusted within range to achieve desired therapeutic effects within therapeutic plasma concentration and in absence of toxic SE

Avoid grapefruit juice

Very high dosages may induce abortion in pregnant women due to oxytocic effect

Extended-release not recommended in children

When quinidine is administered to patients with atrial flutter/fibrillation, the desired pharmacologic reversion to sinus rhythm may (rarely) be preceded by a slowing of atrial rate with a consequent increase in rate of beats conducted to ventricles; the resulting ventricular rate may be very high (greater than 200 beats per minute) and poorly tolerated; this hazard may be decreased if partial atrioventricular block is achieved prior to initiation of quinidine therapy, using conduction-reducing drugs such as digitalis, verapamil, diltiazem, or a β-receptor blocking agent

In patients with sick sinus syndrome, quinidine has been associated with marked sinus node depression and bradycardia

Renal or hepatic dysfunction causes the elimination of quinidine to be slowed, while congestive heart failure causes a reduction in quinidine’s apparent volume of distribution. Any of these conditions can lead to quinidine toxicity if dosage is not appropriately reduced

Because quinidine opposes atrial and A-V nodal effects of vagal stimulation, physical or pharmacological vagal maneuvers undertaken to terminate paroxysmal supraventricular tachycardia may be ineffective in patients receiving quinidine

In patients without implanted pacemakers who are at high risk of complete atrioventricular block(eg, those with digitalis intoxication, second-degree atrioventricular block, or severe intraventricular conduction defects), quinidine should be used only with caution

Pregnancy

There are no adequate and well-controlled studies in pregnant women

Animal reproductive studies have not been conducted

Lactation

Lactation: crosses into breast milk, use extreme caution (AAP Committee states compatible with nursing)

Quinidine has a narrow therapeutic index (serum concentration range: 2—6 mcg/ml). Dosage is individualized based on patient weight, age, renal and hepatic function, clinical goals, patient response, and serum quinidine concentrations.

Quinidine

tablet

  • 200mg (as sulfate)
  • 300mg (as sulfate)

tablet, extended-release

  • 300mg (as sulfate)
  • 324mg (as gluconate)

injectable solution

  • 80mg/mL (as gluconate) – discontinued from U.S. market

About the Author

You may also like these

0