Table 5.

Common Second-Line Medications in the Treatment of SVT in Neonates (Oral therapy)*.

Medication	Class	Dosing	Comments
Sotalol	Class III	Initial: 2 mg/kg/day divided every 8 h; if needed, increase dosage gradually by 1–2 mg/kg/day increments; allow at least 3 days between increments. Proposed target dose: 4 mg/kg/day divided every 8 h (up to 6 mg/kg/day in 1 month-old)	Monitor QTc interval on ECG; monitor for pro-arrhythmia, worsening of ventricular systolic dysfunction
Flecainide	Class IC	Initial: 2 mg/kg/day divided every 12 h; titrate to clinical response. Usual dose: 3–6 mg/kg/day	Monitor QRS duration and QTc interval on ECG; obtain plasma trough concentrations once steady state has been achieved (>5 doses after initiation or change); check interactions with other drugs; avoid concurrent administration with milk or milk-based formula feedings; Amiodarone may increase the serum concentration of Flecainide (decrease Flecainide dose by 50% in the presence of Amiodarone)
Propafenone	Class IC	Initial: 7–10 mg/kg/day divided every 8 h; increased by 20%–30% up to a dose of 18–20 mg/kg/day if indicated	Monitor QRS duration and QTc interval on ECG; check interactions with other drugs
Amiodarone	Class III	Oral loading: 10–20 mg/kg/day in 2 divided doses for 7–10 days; then reduce to 5–10 mg/kg/day once daily and continue for 2–7 months	Monitor QTc interval on ECG; monitor for pro-arrhythmia; dosage adjustment is necessary in substantial hepatic impairment; follow thyroid function tests, metabolic profile including serum glucose, electrolytes, triglycerides, liver function test, ophthalmologic exams; check interactions with other anti-arrhythmic drugs

*The above are suggested doses. Please refer to appropriate references and drug formulary for alternative dosing.