Spironolactone
Aldosterone receptor antagonist with antiandrogenic properties
Mechanism of Action
Spironolactone is a competitive antagonist of the mineralocorticoid receptor (MR), opposing the action of aldosterone in the distal convoluted tubule. This promotes sodium excretion while sparing potassium, producing a diuretic effect without hypokalemia. Spironolactone also binds to androgen receptors (AR) as a weak antagonist and inhibits 17-alpha-hydroxylase and 17,20-desmolase, reducing androgen and testosterone synthesis. These antiandrogenic properties make it useful for androgenic alopecia, hirsutism, and hormone-sensitive conditions in research contexts.
Evidence Level
Clinical Trial - Human
6 studies published
Pharmacology
Molecular Weight
416.6 g/mol
Half-Life
Approximately 1.4 hours (parent); active metabolites 13-17 hours
Bioavailability
Approximately 25% oral bioavailability (variable)