Comparative pharmacodynamics of torasemide and furosemide in patients with oedema

The pharmacodynamics of torasemide (1-isopropyl-3- ([4-(3-methyl-phenylamino)pyridine]-3-sulfonyl)urea), a new potent loop diuretic, were compared to those of furosemide in a double-blind controlled study in 18 patients with oedema of various origin. Torasemide behaved like furosemide in exerting a potent diuretic effect which culminated during the first 4 h after its administration. Nevertheless, torasemide was about 8 times more potent, exerted a longer lasting diuretic effect and was more potassium sparing than furosemide. Torasemide did not accumulate during repeated administration (5 days). It was well tolerated and efficient in the treatment of oedema due to congestive heart failure and hepatic cirrhosis. The long duration of action and the potassium sparing effect of torasemide compared to furosemide are promising features of this new potent loop diuretic.