ATC Group: C03DB Other potassium-sparing agents

Amiloride has mild diuretic and anti-hypertensive activity. It acts primarily in the distal tubule and does not require aldosterone for its action. Amiloride is a mild natriuretic which does not initiate a concomitant decrease in potassium levels.

Triamterene is a potassium-sparing agent. Triamterene inhibits the reabsorption of sodium ions in exchange for potassium and hydrogen ions at that segment of the distal tubule under the control of adrenal mineralocorticoids (especially aldosterone). The fraction of filtered sodium reaching this distal tubular exchange site is relatively small, and the amount which is exchanged depends on the level of mineralocorticoid activity. Thus, the degree of natriuresis and diuresis produced by inhibition of the exchange mechanism is necessarily limited.