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What is quinidine?
Quinidine affects the way that the heart beats. Quinidine is used to treat irregular heartbeat patterns. Quinidine may also be used for purposes other than those listed in this medication guide.

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What is the price of this medication and similar alternatives?

This pricing information is subject to change at the sole discretion of DS Pharmacy. For the most current and up-to-date pricing information, please visit drugstore.com.

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What are the possible side effects of quinidine?

If you experience any of the following serious side effects, stop taking quinidine and seek emergency medical attention or contact your doctor immediately:

• an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives);

• a new or a worsening irregular heartbeat pattern;

• chest pain or chest discomfort;

• ringing in the ears;

• changes in vision;

• dizziness, fainting, or headache;

• rash;

• difficulty breathing;

• abdominal pain, nausea, or vomiting; or

• yellowing of the skin or eyes.

Other, less serious side effects may be more likely to occur. Continue to take quinidine and talk to your doctor if you experience

• mild upset stomach;

• headache;

• decreased appetite;

• diarrhea; or

• muscle weakness.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

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How should I take quinidine?
Take quinidine exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you. Take each dose with a full glass of water. Quinidine may be taken with food to lessen stomach upset. Do not crush, chew, or break any extended- or sustained-release formulations of quinidine. Swallow them whole. If you are not sure whether you have a long-acting form of quinidine, ask your pharmacist, nurse, or doctor. Do not skip doses or change your dosing schedule without talking to your doctor. Changing your schedule could make your condition worse.

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What is the most important information I should know about quinidine?
Contact your doctor immediately if you experience ringing in the ears, changes in vision, dizziness, fainting, a rapid heartbeat, headache, nausea, a rash, or difficulty breathing. Do not skip doses or change your dosing schedule without talking to your doctor. Changing your schedule could make your condition worse. Quinidine may be taken with food to lessen stomach upset. Do not crush, chew, or break any extended- or sustained-release formulations of quinidine. Swallow them whole. If you are not sure whether you have a long-acting form of quinidine, ask your pharmacist, nurse, or doctor.

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What happens if I miss a dose?
Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and take only the next regularly scheduled dose. Do not take a double dose of this medication. A double dose could be dangerous.

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What other drugs will affect quinidine?
Before taking quinidine, tell your doctor if you are taking any of the following medicines: pimozide (Orap); itraconazole (Sporanox); ziprasidone (Geodon); voriconazole (VFEND); thioridazine (Mellaril) or mesoridazine (Serentil); ritonavir (Norvir); dolasetron (Anzemet); digoxin (Lanoxin); warfarin (Coumadin); erythromycin (E-Mycin, Eryc, E.E.S., others); sparfloxacin (Zagam), levofloxacin (Levaquin), grepafloxacin (Raxar), gatifloxacin (Tequin); another medicine to treat irregular heartbeats such as bepridil (Vascor), dofetilide (Tikosyn), procainamide (Procan SR, Procanbid, Pronestyl), disopyramide (Norpace), and others;

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Can I take this if I am pregnant or trying to get pregnant or if I am breastfeeding?

Quinidine has been assigned to pregnancy category C by the FDA. Animal studies have not been reported. There are no controlled data in human pregnancy. Quinidine should be given during pregnancy only when benefit outweighs risk.

Quinidine crosses the placenta, with umbilical cord blood to maternal serum concentration ratios ranging from 0.2 to 0.8. Quinidine, when compared to many other cardiovascular drugs, is considered relatively safe for the fetus. Quinidine has been used successfully and safely to treat resistant fetal tachyarrhythmias and to treat acute malaria in pregnant women. Neonatal thrombocytopenia has been reported after maternal ingestion of quinidine. Data from the Michigan Medicaid Birth Defects Study has failed to reveal an association between quinidine and congenital abnormalities (written communication, Franz Rosa, MD, Food and Drug Administration, 1994). This was a retrospective study of 229,101 completed pregnancies between 1985 and 1992, of which 17 were exposed to quinidine at some time during the first trimester, and 68 were exposed to the drug at any time during pregnancy. Of these pregnancies, a single birth defect was observed. This observation did not achieve statistical significance. There were no observations of cardiovascular defects, cleft palate, spina bifida, polydactyly, limb reduction, or hypospadias. These data do not support an association between quinidine and birth defects.

Quinidine is excreted into human milk. The manufacturer reports that quinidine is present in human milk at levels slightly lower than those in maternal serum. The effects in the nursing infant is unknown. The manufacturer recommends that due to the potential for serious adverse reactions in nursing infants, a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

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Who should NOT use this medication?

• Complete AV block with an AV junctional or idioventricular pacemaker, in patients with left bundle-branch heart block or other severe intraventricular conduction defects (especially with marked widening of the QRS complex), in patients with ectopic impulses and rhythms due to escape mechanisms, and in patients with cardiac glycoside-induced AV conduction disorders.
• History of quinidine- or quinine-associated thrombocytopenic purpura.
• Myasthenia gravis and other conditions that might be adversely affected by anticholinergic effects.
• Known hypersensitivity to quinidine.

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What does my medication look like?
Quinidine is available with a prescription under several brand and generic names. Ask your pharmacist any questions you have about this medication, especially if it is new to you. Quinora 300 mg--round, white tablets Quinidex Extentabs 300 mg--round, white, sustained-release tablets Quinaglute Dura-Tabs 324 mg--round, white, sustained-release tablets Cardioquin 275 mg--round, white, scored tablets

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What happens if I overdose?
Seek emergency medical attention. Symptoms of a quinidine overdose include confusion, tiredness, seizures, difficulty breathing, fainting, a rapid heartbeat, and coma.

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What should I discuss with my healthcare provider before taking quinidine?
Before taking quinidine, tell your doctor if you have had an allergic reaction or the development of blood problems (e.g., thrombocytopenic purpura) due to previous treatment with quinidine or quinine; any other type of heart disease or heart problems; liver disease; kidney disease; or myasthenia gravis (a nerve-muscle disorder). You may not be able to take quinidine, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.

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Can I stop taking the medication if I feel better?
As a general rule, you should always take your medications exactly as prescribed and do not change the dosage or stop taking the medication without first discussing it with your healthcare provider.

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I am on so many medications; do I have to take them all?
This is called polypharmacy—many different medications being used at the same time by one person. Sometimes, being on multiple medications is acceptable and appropriate but at other times it may be problematic. If you are receiving your medications from multiple physicians you need to ensure that they all know what medications you are taking. The best way to do this is to make a list of all the medications you are currently using, including all nutritional supplements, homeopathic remedies, vitamins and over-the-counter drugs (if possible, also include all the diseases you have been diagnosed with). Give a copy to every doctor who takes care of you so they have it on file, this way they can avoid duplicating medications and perhaps even try to consolidate some. After every doctor's visit remember to update the list accordingly. Also, as much as you possibly can, try to use the same pharmacy to fill all your prescriptions, this way any potential drug interactions can be caught and averted.

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Where can I get more information?
More Information

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