Indications & Dose:
- Ventricular arrhythmias, SVT, atrial flutter: 2 mg/kg IV over 10 min, followed by 0.8 mg/kg/h for 6h, then 0.4 mg/kg/h for remainder (ref)
- Study used Nexterone (premixed solution); appears safer
- Ventricular fibrillation, pulseless ventricular tachycardia unresponsive to defibrillation (class IIb evidence only): 5 mg/kg IV
Mechanism of action:
- blocks multiple K+ channels, activated Na+ channels, Ca++ channels
- α-blocking and nonselective β-blocking effects
- Vaughan Williams class III with class Ia, II and IV characteristics
Adverse effects:
- Anaphylaxis and acute allergic reactions with formulations containing polysorbate 80 and benzyl alcohol
- Urticaria, facial angioedema, erythema, pruritus – resolve with steroid and antihistamines (ref)