- See: -
Class I Agents - Discussion: - for prevention of PAT,
atrial fibrillation,
ventricular tachycardia, PVCs; - acts by depressing automaticity and conduction of the myocardium; -
Class I antiarrhythmic;
- Adult: PAC, PVC: - 200-300 mg PO tid-qid; - PAT: 400-600 mg PO q2-3hr until terminated;
- Conversion of atrial fibrillation or
flutter: - use after digitalization: 200 mg q 2-3hr for 8 doses; - then increase daily dose to maximum of 3-4 gm or until normal rhythm; - follow serum levels if possible;
- Precautions: - Quinidine will produce doubling of
Digitalis plasma level; -
Digitalization is indicated before starting quinidine in order to block AV nodal conduction; - if quinidine is used before digitization, it may increase AV nodal conduction and ventricular rate;
- Contraindications: - Complete AV block; -
Digitalis intoxication - Complete bundle branch block;
