Torasemide in advanced renal failure

Summary

In patients with advanced renal failure, high doses of loop diuretics are required to promote negative sodium and water balance and to treat hypertension. Torasemide is a new loop diuretic that has a high bioavailability of 90% and a plasma half-life of 3–5 hours, which remains unchanged in chronic renal failure. Even in patients with advanced renal failure, intravenous and oral high-dose torasemide proves effective in increasing fluid and sodium excretion in a dose-dependent manner. A number of studies in renal failure patients provide evidence that, on a weight-by-weight basis, the ratio of diuretic potency between torasemide and furosemide is 1:2.5 after oral dosing and 1:1 after intravenous administration. The lack of a substantial calciuretic effect of torasemide in chronic renal disease needs further confirmation. Two controlled multicenter clinical trials comparing high oral doses of furosemide and torasemide in patients with end-stage renal disease requiring maintenance hemodialysis demonstrated a substantial increase in urinary volume and electrolyte excretions in patients receiving 100 or 200 mg oral torasemide once daily. A dose of 200 mg oral torasemide appears equally natriuretic to oral furosemide 500 mg, whereas the antihypertensive effect of torasemide is more pronounced. Neither torasemide nor furosemide in the above doses has a negative influence on the neurological status of hemodialysis patients.