For sustained supraventricular tachycardia, diltiazem (0.25 mg/kg IV), esmolol (0.05 to 0.1mg/kg, titrated upward to a cumulative dose of 0.5 mg/kg IV), or propranolol (0.04 to 0.1 mg/kg IV slowly to effect) can be administered in an attempt to slow the ventricular rate in emergent situations.