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What is quinidine?
Quinidine is an antiarrhythmic agent and antimalarial drug.
Is quinidine available as a generic drug?
GENERIC AVAILABLE: Yes
Do I need a prescription for quinidine?
What are the side effects of quinidine?
The most common side effects are:
Other important side effects include:
- Irregular heartbeat
- Chest pain
- Skin rash
- Hearing changes (ringing or loss of hearing)
- Vision changes (blurred or light sensitivity)
- Unusual bleeding
If patients experience any of the above side effects, they should call their doctor immediately.
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What is the dosage for quinidine?
- For adults, the dosage range for quinidine gluconate is from 648 to 2592 mg/day.
- For adults, the dosage range for quinidine sulfate is from 400 to 4000 mg/day.
- For adults, the dosage range for quinidine gluconate injection is 400 to 2400 mg/day.
Which drugs or supplements interact with quinidine?
- Azole antifungals such as ketoconazole (Nizoral), fluconazole (Diflucan), itraconazole (Sporanox PulsePak), voriconazole (VFEND), posaconazole (Noxafil), and protease inhibitor/antiretroviral drugs such as indinavir (Crixivan), and saquinavir (Invirase) should not be used with quinidine since their concomitant use can increase quinidine levels by inhibiting removal of quinidine by the liver. Increased quinidine levels can increase the risk of quinidine toxicity and cardiac arrhythmias.
- Phenothiazines such as thioridazine (Mellaril), an antipsychotic drug, and tricyclic antidepressants such as amitriptyline (Elavil, Endep) should not be used with quinidine since they can cause cardiac arrhythmias, and their use with quinidine increases the risk of cardiac arrhythmias.
- Quinidine increases the action of the blood thinner warfarin (Coumadin, Jantoven), due to synergistic effects and can lead to excessive blood thinning and bleeding. A decrease in warfarin dose usually is required. Blood levels of digoxin (Lanoxin) are raised by quinidine due to a reduction in removal or reduced distribution in the body of digoxin. This can give rise to intoxication with digoxin, and it is important to reduce the dose of digoxin to prevent toxicity.
- Removal of quinidine by the liver is accelerated by phenobarbital, phenytoin (Dilantin), and rifampin (Rifamate), requiring an increase in quinidine dose.
- With the exact mechanism not known, amiodarone (Cordarone), another type of antiarrhythmic drug, may decrease removal of quinidine by the kidneys or liver giving rise to elevated quinidine blood levels, which may result in life-threatening arrhythmias, including torsades de pointes. It is important, therefore, to decrease quinidine doses when it is given concomitantly with amiodarone.
- Cimetidine (Tagamet) increases quinidine levels by decreasing the elimination of quinidine giving rise to elevated quinidine serum levels that may lead to quinidine toxicity.
Latest Heart News
Is quinidine safe to take if I'm pregnant or breastfeeding?
What else should I know about quinidine?
What preparations of quinidine are available?
- Tablets: 200, 300, and 324 mg.
- Injections: 800 mg.
How should I keep quinidine stored?
- Quinidine should be stored at room temperature, 20 C - 25 C (68 F - 77 F).
- It should be dispensed in well-closed, light-resistant container.
Quinidine (Discontinued Brands: Cardioquine, Cin-Quin, Duraquin, Quinidex, Quinora, Quinact, Quinatime, Quinaglute, Quinalan) is an antiarrhythmic medication prescribed for abnormal heart rhythms such as atrial fibrillation, atrial flutter, and ventricular arrhythmias such as paroxysmal ventricular tachycardia. Quinidine also is prescribed to treat malaria. Review side effects, drug interactions, warnings and precautions, and pregnancy and breastfeeding safety information prior to taking this medication.
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Related Disease Conditions
Atrial Fibrillation (AFib, AF)
Atrial fibrillation (AF or AFib) is an abnormality in the heart rhythm, which involves irregular and often rapid beating of the heart. Symptoms may include heart palpitations, dizziness, fainting, fatigue, shortness of breath, and chest pain. Atrial fibrillation treatment may include medication or procedures like cardioversion or ablation to normalize the heart rate.
Malaria is a disease that is spread by the bite of an infected Anopheles mosquito. Malaria symptoms include fever, chills, nausea, vomiting, and body aches. Treatment involves supportive care and antibiotics.
Palpitations are uncomfortable sensations of the heart beating hard, rapidly, or irregularly. Some types of palpitations are benign, while others are more serious. Palpitations are diagnosed by taking the patient history and by performing an EKG or heart monitoring along with blood tests. An electrophysiology study may also be performed. Treatment of palpitations may include lifestyle changes, medication, ablation, or implantation of a pacemaker. The prognosis if palpitations depends on the underlying cause.
Lupus (Systemic Lupus Erythematosus or SLE)
Systemic lupus erythematosus is a condition characterized by chronic inflammation of body tissues caused by autoimmune disease. Lupus can cause disease of the skin, heart, lungs, kidneys, joints, and nervous system. When only the skin is involved, the condition is called discoid lupus. When internal organs are involved, the condition is called systemic lupus erythematosus (SLE).
Premature Ventricular Contractions (PVC)
Premature ventricular contractions (PVC) are premature heartbeats originating from the ventricles of the heart. PVCs are premature because they occur before the regular heartbeat. There are many causes of premature ventricular contractions to include: heart attack, high blood pressure, congestive heart failure, mitral valve prolapse, hypokalemia, hypoxia, medications, excess caffeine, drug abuse, and myocarditis.
How the Heart Works: Sides, Chambers, and Function
The heart is a very important organ in the body. It is responsible for continuously pumping oxygen and nutrient-rich blood throughout your body to sustain life. It is a fist-sized muscle that beats (expands and contracts) 100,000 times per day, pumping a total of five or six quarts of blood each minute, or about 2,000 gallons per day.
Abnormal Heart Rhythms (Heart Rhythm Disorders)
Heart rhythm disorders vary from minor palpitations, premature atrial contractions (PACs), premature ventricular contractions (PVCs), sinus tachycardia, and sinus brachycardia, to abnormal heart rhythms such as tachycardia, ventricular fibrillation, ventricular flutter, atrial fibrillation, atrial flutter, paroxysmal supraventricular tachycardia (PSVT), Wolf-Parkinson-White syndrome, brachycardia, or heart blocks. Treatment is dependent upon the type of heart rhythm disorder.
Paroxysmal Supraventricular Tachycardia (PSVT)
Paroxysmal supraventricular tachycardia (PSVT) is an abnormal conduction of electricity in particular areas of the heart. PSVT was referred to at one time as paroxysmal atrial tachycardia or PAT, however, the term PAT is reserved for as specific heart condition. Symptoms of PSVT include weakness, shortness of breath, chest pressure, lightheadedness, and palpitations. PSVT is treated with medications or procedures that return the heart to its normal electrical pattern.
Thrombocytopenia (Low Platelet Count)
Thrombocytopenia (low platelet count) refers to a decreased number of platelets in the blood. Symptoms of thrombocytopenia include: Increased bruising Spontaneous bleeding Small, purple spots under the skin called purpura There are many causes of thrombocytopenia such as decreased platelet production (viral infections for example rubella, mumps, chickenpox, hepatitis C, and HIV); increased platelet destruction or consumption (for example sulfonamide antibiotics, heparin, blood transfusions, and lupus); or increased splenic sequestration (enlarged spleen due to conditions for example liver disease, blood cancers, and more). Treatment of thrombocytopenia depends on the cause.
Atrial Fibrillation Symptoms (AFib Warning Signs)
Atrial fibrillation or AFib is a type of hear rhythm abnormality. Early warning signs and symptoms of atrial fibrillation include chest pain, palpitations, shortness of breath, and lightheadedness. Treatment for atrial fibrillation includes medical procedures, surgery, and medication.
Atrial Fibrillation (AFib) Treatment Drugs
Atrial fibrillation (AFib) is a heart rhythm disorder that causes irregular and often rapid heartbeat. The medications to treat AFib include beta-blockers, blood thinners, and heart rhythm drugs. Atrial fibrillation drugs can cause serious side effects like seizures, vision changes, shortness of breath, fainting, other abnormal heart rhythms, excessive bleeding while coughing or vomiting, blood in the stool, and bleeding into the brain.
Treatment & Diagnosis
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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.