Class
Description
Onset and Duration
Indications
Contraindications
Adverse Reactions
Drug Interactions
How Supplied
Dosage and Administration
Special Considerations
Antidysrhythmic (class la)
Procainamide suppresses phase-4 depolarization in normal ventricular muscle and Purkinje fibers, reducing the automaticityof ectopic pacemakers. It also suppresses reentry dyrhythmias by slowing intraventricular conduction. Procainamide may be effective in treating PVCs and recurrent ventricular tachycardia that cannot be controlled with lidocaine.
Suppressing PVCs refractory to lidocaine
Suppressing ventricular tachycardia (with a pulse) refractory to lidocaine
Suppressing ventricular fibrillation refractory to lidocaine when bretylium tosylate is not readily available
PSVTs with wide-complex tachycardia of unknown origin (drug of choice when associated with WPW)
Second- and third-degree AV block
Digitalis toxicity
Torsades de pointes
Hypotension
Bradycardia
Reflex tachycardia
AV block
Widened QRS
Prolonged PR or QT interval
PVCs
Ventricular tachycardia, ventricular fibrillation, asystole
CNS depression
Confusion
Seizure
There are no significant drug interactions with other emergency medications.
1 g in 10-ml vial (100 mg/ml)
1 g in 2-ml vials (500 mg/ml) for infusion
Pregnancy safety: Category C.
Procainamide has potent vasodilating and inotropic effects.
Rapid injection may cause procainamide-induced hypotension.
Carefully monitor vital signs and ECG.
Administer cautiously to patients with asthma, digitalis-induced dysrhythmias, acute myocardial infarction, or cardiac, hepatic, or renal insufficiency.