Quinidine

Quinidine is a prescription medication used to treat abnormal heart rhythms. It is also used to treat malaria. Quinidine belongs to a group of drugs called antiarrhythmics. These work by making your heart more resistant to abnormal activity. 

This medication comes in tablet form and is taken up to 3 times a day. This medication comes in extended release tablet form and is taken up to 3 times a day. Do not crush or chew quinidine tablets. Tablets can be broken in half. This medication is also available in an injectable form to be given directly into a vein (IV) by a healthcare professional. 

Common side effects of quinidine include diarrhea, lightheadedness, and headache. Quinidine can also cause dizziness. Do not drive or operate heavy machinery until you know how quinidine affects you. 

CYP2D6 is a protein in your body that is involved in the elimination of quinidine and other drugs from your body. Some patients have less of this protein in their bodies, affecting how much of the drug gets eliminated. Levels of CYP2D6 can vary greatly between individuals, and those having less of this protein are known as "poor metabolizers." 

CYP2D6 testing is done to determine whether you are a poor metabolizer. If you are a poor metabolizer, the levels of quinidine in your blood can become too high. As a result you may be at an increased risk of having more side effects from quinidine. 

Your doctor may adjust your dose of quinidine if you are a poor metabolizer.

Quinidine is a prescription medication used to treat abnormal heart rhythms and malaria.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information. 

Quinidine may be found in some form under the following brand names:

• Cardioquin

• Nuedexta

• Quin-G

• Quin-Release

• Quinora