Class
Description
Onset and Duration
Indications
Contraindications
Adverse Reactions
Drug Interactions
How Supplied
Dosage and Administration
Special Considerations
Antidysrhythmic (class III)
Bretylium is an adrenergic neuronal blocking agent that has both adrenergic and direct myocardial effects. Although the antidysrhythmic action of brethylium is poorly understood, like lidocaine it has been found to be effective in treating ventricular fibrillation and ventricular tachycardia. Bretylium produces a prompt increase in ventricular fibrillation threshold, perhaps through postganglionic adrenergic blockade. At present, its use is in reserved for patients who fail to respond to lidocaine or other first-line antidysrhythmics.
Treatment of VF and VT refractory to lidocaine
None in the treatment of life-threatening dysrhythmias
Vertigo
Dizziness
Syncope
Hypotension
Bradycardia
Increase in PVCs
Angina pectoris
Digoxin toxicity may be aggravated by the initial release of norepinephrine for bretylium.
Parenteral: 50 mg/ml in 10-ml vials
Ventricular fibrillation
5 mg/kg rapid IV bolus. Repeated at a dose of 10 mg/kg (maximum dose of 30-35 mg/kg).
Refractory or recurrent ventricular tachycardia
Dilute 500 mg (10 ml) to 50 ml, and administer 5-10 mg/kg IV over 8-10 min.
May be repeated in 1-2 hr, and if needed, q 6-8 hr thereafter.
Bretylium may be administered as an IV infusion at a rate of 1-2 mg/min.
Pediatric
5 mg/kg rapid IV; may be increased to 10 mg/kg
Pregnancy safety: Safety has not been established.
Postural hypotension occurs in 50% of patients receiving bretylium (patients should be kept in supine position).
In ventricular fibrillation, bretylium is usually only effective if followed by defibrillation.
Ventricular tachycardia does not respond to bretylium as rapidly as ventricular fibrillation.