Procan SR, a brand name under the generic Procainamide, is a cardiac drug that treats a variety of heart problems like atrial and ventricular premature contractions or seriously irregular heartbeat patterns.
Indications and Actions
Procainamide increases the effective refractory period of the atria, and to a lesser extent the bundle of His-Purkinje system and ventricles of the heart. It decreases myocardial excitability, slows conduction velocity, and may depress myocardial contractility. Its therapeutic effects include suppression of arrhythmias.
Route and Dosage
The oral dose and interval of administration should be adjusted for the individual patient, based on clinical assessment of the degree of underlying myocardial disease, the patient’s age, and renal function (“Procan Sr” 3). Judith Deglin groups together the route of administration, including the recommended dosages expressed in terms in which they are usually prescribed:
- PO (Adults): Atrial arrhythmias – 1.25 g initially, then 750 mg 2 hr later, then 0.5-1g q 2-3 hr followed by maintenance dosing of 0.5-1g q 4-6 hr or 1 g q 12 hr as sustained-release tablets. Ventricular arrhythmias – 50 mg/kg/day in divided doses q 3 hr or q 12 hr for sustained-release tablets. Lower doses/longer dosing intervals are recommended for geriatric patients or those with renal, hepatic, or cardiac insufficiency.
- PO (Children): 12.5 mg/kg (375 mg/m2) 4 times daily
- IM (Adults): 50 mg/kg/day in divided doses q 3-6 hr.
- IV (Adults): 100 mg q 5 min until arrhythmia is abolished or 1000 mg have been given; wait at least 10 min until further dosing or loading infusion of 500-600 mg over 25-30 min followed by maintenance infusion of 2-6 mg/min. (p. 874-875)
Adverse reactions to Procan SR include seizures, confusion, dizziness, asystole, heart block, ventricular arrhythmias, hypotension, diarrhea, anorexia, bitter taste, nausea, vomiting, rashes, eosinophilia, leucopenia, thrombocytopenia, chills, drug-induced systemic lupus syndrome, and fever.
It is available in tablets (250 mg, 375 mg, 500 mg), sustained-release tablets (500 mg, 1000 mg), capsules (250 mg, 375 mg, 500 mg), and injection (100 mg/ml in 10-ml vials, 500 mg/ml in 2-ml vials and 2- and 4-ml pre-filled syringes).
Deglin, Judith Hopfer and Vallerand, April Hazard. Davis’s Drug Guide For Nurses 9th Edition. Philadelphia, USA: F.A. Davis Company, 2005.
“Procan Sr”. RxList The Internet Drug Index. 10 November 2007 <http://www.rxlist.com/cgi/generic/procainexr_ids.htm>.