Classification: antiarrhythmic; antifibrillatory activity
  • used for ventricular arrhythmias when other agents of choice are ineffective
  • suppression of ventricular fibrillation occurs within minutes but suppression of ventricular tachycardia or premature contractions may not begin until 20 minutes to 6 hours after administration
  • should not be used in place of more rapidly acting antiarrhythmic agents
  • not effective in treating Torsades de Pointes 
  • IV Direct:
    • 5 - 10 mg/kg IV ADC
  • IV Infusion:
    • 1 - 2 mg/min
Administration: IV Infusion:
2 gm/500 mL D5W, NS, RL
  • for treatment of ventricular fibrillation, should be given undiluted as quickly as possible
  • administer intermittent doses by IV infusion over 8 minutes, diluted to a concentration of 10 mg/mL (ie. 500 mg/50 mL)
  • reduce dosage in renal failure
Adverse Effects:
  • transient hypertension at start of therapy
  • hypotension
  • dysrhythmias
  • nausea + vomiting with rapid IV administration
  • aggravates digoxin toxicity
  • hyperthermia
  • caution in renal failure; dose reduction required
  • in complete heart block or type II second degree heart block unless functional pacemaker in place (can suppress a ventricular escape rhythm)
Drug Interactions:
  • bretylium + quinidine = antagonism of bretylium's antiarrhythmic effect
  • bretylium + sympathomimetics = enhanced sympathomimetic effect
Monitoring Therapy:
  • HR
  • ECG 
  • BP
  • cardiac index
  • electrolytes
  • arterial lactate
  • digoxin level (if patient on digoxin)
CCTC Protocol:
  • May be administered by IV infusion by an approved RN in CCTC.
  • Continuous infusions must be administered by infusion pump.


Lynne Kelly, Pharmacist, CCTC
Brenda Morgan, Clinical Nurse Specialist, CCTC
Last Update: August 7, 2006

LHSCHealth Professionals

Last Updated March 24, 2009 | © 2007, LHSC, London Ontario Canada