- See: -
Class I Agents
- Discussion: - for supraventricular and ventricular arrhythmia (if
lidocaine has failed); - is
Class I antiarrhythmic, similar to
quinidine; - requires a relatively long time to achieve therapeutic levels; - after new onset fibrillation or flutter have been controlled, add
quinidine or procainamide to help maintain sinus rhythm; - procainamide may be started 375 mg PO q4hr or SR 500-1gm PO q6hr; - typically the patient will be placed on
Digoxin prior to procanamide;
- Dosing: -
Dilution: 1 gm/250 ml D5W; (4 mg/ml)
- Urgent situation: - 1gm given over 30 min, however, no > 20 mg/min; - Monitor BP q2-3min until total loading dose is given; - or ... 50mg IV q5min until arrhythmia disappears or hypotension ensues or
QRS is widened by 50%, or dose > 1gm; (also look for
QT widening) - then continuous infusion 1-4 mg/min drip (set up drip as for
lidocaine); -
Non-Urgent situations: - 1-1.25 gm is given over at least 1-1.5 hr; -
Chronic Dosing: - 50 mg/kg/day in divided doses q3-6hr;
- Precautions: - observe for cardiac depression during loading; - reduce dose w/ renal failure; - reduced rate of administration if hypotension is induced or if there is > 50% prolongation of the QRS complex or
QT interval (toxicity); - may cause a Lupus like syndrome; - Supplied: cap: 250, three hundren and seventy five, 500, Inj 100 mg/ml; sustained release: 250 mg, and 500 mg;
