Spironolactone
Spironolactone is a potassium sparing diuretic like [eplerenone] that competitively inhibits mineralocorticoid receptors in the distal convoluted tubule to promote sodium and water excretion and potassium retention. Spironolactone was originally developed purely for this ability before other pharmacodynamic properties of the drug were discovered. It is indicated to treat a number of conditions including heart failure, deem, hyperaldosteronism, adrenal hyperplasia, hypertension, and nephrotic syndrome. Off label uses of spironolactone involving its antiandrogenic activity include hirsutism, female pattern hair loss, and adult acne vulgaris. Spironolactone is also frequently used in medical gender transition.  Spironolactone was developed in 1957, marketed in 1959, and approved by the FDA on January 21, 1960.