July 1973

Use of a New Diuretic Agent (Metolazone) in Patients With Edema and Ascites

Author Affiliations


From the Department of Medicine, Temple University Health Sciences Center, Philadelphia. Dr. Lowenthal is now with Walter Reed Army Institute of Research, Washington, DC.

Arch Intern Med. 1973;132(1):38-41. doi:10.1001/archinte.1973.03650070030005

Metolazone, a new diuretic agent, was administered to patients with ascites and edema. After injection of a single dose, natriuresis, diuresis, and kaliuresis began promptly and persisted for two to three days. This uniquely prolonged duration of action is attributable to avid protein-binding and enterohepatic recycling of the drug, which result in slow disappearance from the body. In three of four responsive patients potassium excretions increased only slightly, despite moderately large increases in sodium excretion. Three other patients who were resistant to metolazone demonstrated kaliuresis even though the daily rate of sodium excretion increased by only a few milliequivalents. Metolazone appears to be a clinically useful diuretic agent which continues to act for an unusually long time after administration of a single dose. During metolazone therapy, natriuresis and kaliuresis may occur independently of each other.