Conversion from Oral Torsemide to IV Furosemide

Introduction to Conversion Ratios

When converting from oral torsemide to IV furosemide for patients on chronic diuretic therapy, the initial IV furosemide dose should be at least equivalent to the effective oral dose using a conversion ratio, as recommended by the European Society of Cardiology 1
The European Heart Society suggests that for diuretic-naïve patients, starting with 20-40 mg IV furosemide regardless of prior torsemide dose is advisable 1, 3

The European Heart Journal recommends that IV furosemide can be given as intermittent boluses or continuous infusion, with the dose and duration adjusted according to the patient's clinical status 1
Regular monitoring of symptoms, urine output, renal function, and electrolytes during IV furosemide administration is advised by the European Heart Journal 1, 4
Total furosemide dose should remain <100 mg in the first 6 hours and <240 mg during the first 24 hours, as suggested by the European Journal of Heart Failure 2, 3

In cases of diuretic resistance, the European Heart Journal suggests considering combination therapy with thiazide diuretics or aldosterone antagonists rather than excessive dose escalation 1, 2
The European Heart Journal also notes that IV furosemide may transiently worsen hemodynamics for 1-2 hours after administration by increasing systemic vascular resistance and left ventricular filling pressures 4

Using a 1:1 conversion ratio will result in underdosing of furosemide, as noted by the European Journal of Heart Failure 2
Overly aggressive furosemide dosing can lead to electrolyte abnormalities, dehydration, and hypotension, as warned by the European Heart Journal 1