The Relative Potency of Competitive and Non-competitive Mineralocorticoid Antagonists in Man

Abstract

Mineralocorticoid antagonists are used clinically in conditions of primary mineralocorticoid excess, such as primary hyperaldosteronism, and in disease states characterised by secondary aldosteronism, for example, chronic liver disease and the nephrotic syndrome. They also find wide use in the treatment of essential hypertension, cardiac failure, and diuretic-induced hypokalaemia, although mineralocorticoid excess has not been demonstrated convincingly in these conditions. The mineralocorticoid antagonists available are the specific competitive aldosterone antagonists, among which spironolactone is the standard drug [1], and the non-competitive physiological antagonists, amiloride and triamterene. The latter drugs have a direct membrane action, principally on the distal renal tubule, and do not require the presence of aldosterone or other mineralocorticoids, whereas spironolactone is pharmacologically inactive in the absence of mineralocorticoids.