March 1968

Mode of Action of Ethacrynic Acid in Congestive Heart Failure

Author Affiliations

Portland, Ore

From the Renal Laboratory, Division of Cardiovascular-Renal Disease, Department of Medicine, University of Oregon Medical School, Portland, Ore.

Arch Intern Med. 1968;121(3):235-242. doi:10.1001/archinte.1968.03640030027004

The renal response to a single intravenous dose of ethacrynic acid was evaluated in ten patients with cardiac decompensation. Following infusion of the drug, a prompt increase in urine flow occurred lasting for approximately two hours. During this diuresis, renal function studies disclosed a fall in tubular reabsorption of water, sodium and chloride, and an increase in osmolar clearance. These findings are compatible with a blockade of coupled sodium chloride reabsorption in either the ascending loop of Henle or early distal tubule or both, but do not exclude a redistribution of intrarenal blood flow as contributing significantly to ethacrynic acid's mode of action. Distal tubular exchange between sodium and potassium-hydrogen does not seem to be affected by this diuretic.