Alterations induced by large doses of furosemide in chronic renal insufficiency.

Eleven patients with different degrees of renal failure with creatinine clearances between 7 and 32 ml/min have been studied. After a standard water overload and control periods of clearances, furosemide 1 g was given/i.v. There followed significant increase of renal plasma flow and glomerular filtration rate. In one case the increase was maintained during a follow up period of 3 hours. A significant increase was evident in phosphate, uric acid, sodium, potassium, and calcium clearances, as well as an increase in the sodium delivery to the distal nephron and a decrease in tubular reabsorption of phosphate. All this may be interpreted as the result of renal vasodilation induced by furosemide and its effect upon the proximal tubule and on Henle's loop.