quinidine, Quinidine Gluconate, Quinidine Sulfate (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

Quinidine blocks the normal effect of the vagus nerve on the heart, causing an increase in the rate at which the heart beats. Quinidine reduces the force of contraction of heart muscle cells, and therefore may impair the pumping efficiency of failing heart muscle as in congestive heart failure. Quinidine blocks alpha-receptors on the muscle cells that surround arteries which relaxes the muscle cells, lowers blood pressure ,and can cause excessively low blood pressure when combined with other drugs that also relax these muscle cells. Quinidine was approved by the FDA in July 1950.

PRESCRIBED FOR: Quinidine is an antiarrhythmic drug used in the treatment of abnormal heart rhythms, such as: atrial fibrillation, atrial flutter, and ventricular arrhythmias such as paroxysmal ventricular tachycardia. Quinidine also is used to treat malaria.

SIDE EFFECTS: 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) or
  • unusual bleeding.
Medically Reviewed by a Doctor on 3/30/2015

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