Drug Groups

approved

Description

A derivative of procaine with less CNS action. [PubChem]

Indication

For the treatment of life-threatening ventricular arrhythmias.

Pharmacology

Procainamide is an agent indicated for production of local or regional anesthesia and in the treatment of ventricular tachycardia occurring during cardiac manipulation, such as surgery or catheterization, or which may occur during acute myocardial infarction, digitalis toxicity, or other cardiac diseases. The mode of action of the antiarrhythmic effect of Procainamide appears to be similar to that of procaine and quinidine. Ventricular excitability is depressed and the stimulation threshold of the ventricle is increased during diastole. The sinoatrial node is, however, unaffected.

Toxicity

LD₅₀=95 mg/kg (rat, IV); LD₅₀=312 mg/kg (mouse, oral); LD₅₀=103 mg/kg (mouse, IV); LD₅₀=250 mg/kg (rabbit, IV)

Affected Organisms

Biotransformation

Hepatic

Absorption

75 to 95%

Half Life

~2.5-4.5 hours

Protein Binding

15 to 20%

Elimination

Trace amounts may be excreted in the urine as free and conjugated p-aminobenzoic acid, 30 to 60 percent as unchanged PA, and 6 to 52 percent as the NAPA derivative.

Distribution

* 2 L/kg

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