A class I anti-arrhythmic agent (one that interferes directly with the depolarization of the cardiac membrane and thus serves as a membrane-stabilizing agent) with a depressant action on the heart similar to that of guanidine. It also possesses some anticholinergic and local anesthetic properties. [PubChem]
Indication
For the treatment of documented ventricular arrhythmias, such as sustained ventricular tachycardia, ventricular pre-excitation and cardiac dysrhythmias. It is a Class Ia antiarrhythmic drug.
Pharmacology
Disopyramide is an antiarrhythmic drug indicated for the treatment of documented ventricular arrhythmias, such as sustained ventricular tachycardia that are life-threatening. In man, Disopyramide at therapeutic plasma levels shortens the sinus node recovery time, lengthens the effective refractory period of the atrium, and has a minimal effect on the effective refractory period of the AV node. Little effect has been shown on AV-nodal and His-Purkinje conduction times or QRS duration. However, prolongation of conduction in accessory pathways occurs.
Toxicity
LD50=580 mg/kg in rats
Affected Organisms
Humans and other mammals
Biotransformation
Hepatic
Absorption
Nearly complete
Half Life
6.7 hours (range 4-10 hours)
Protein Binding
50%-65%
Elimination
In healthy men, about 50% of a given dose of disopyramide is excreted in the urine as the unchanged drug, about 20% as the mono-N-dealkylated metabolite and 10% as the other metabolites.
A monocarboxylic acid amide that is butanamide substituted by a diisopropylamino group at position 4, a phenyl group at position 2 and a pyridin-2-yl group at position 2. It is used as a anti-arrhythmia drug.
有害性 (Xn)
