<p>Spironolactone is a potassium sparing diuretic like <a href="https://go.drugbank.com/drugs/DB00700">eplerenone</a> that competitively inhibits mineralocorticoid receptors in the distal convoluted tubule to promote sodium and water excretion and potassium retention.<sup class="text-reference-group"><a class="reference-popover-link" data-content="Sica DA: Pharmacokinetics and pharmacodynamics of mineralocorticoid blocking agents and their effects on potassium homeostasis. Heart Fail Rev. 2005 Jan;10(1):23-9. doi: 10.1007/s10741-005-2345-1. (PubMed ID 15947888)" href="#reference-A11837">8</a></sup>. Spironolactone was originally developed purely for this ability before other pharmacodynamic properties of the drug were discovered.<sup class="text-reference-group"><a class="reference-popover-link" data-content="Sica DA: Pharmacokinetics and pharmacodynamics of mineralocorticoid blocking agents and their effects on potassium homeostasis. Heart Fail Rev. 2005 Jan;10(1):23-9. doi: 10.1007/s10741-005-2345-1. (PubMed ID 15947888)" href="#reference-A11837">8</a>,<a class="reference-popover-link" data-content="BOLTE E, VERDY M, MARC-AURELE J, BROUILLET J, BEAUREGARD P, GENEST J: Studies on new diuretic compounds: spirolactone and chlorothiazide. Can Med Assoc J. 1958 Dec 1;79(11):881-8. (PubMed ID 13608362)" href="#reference-A178246">11</a></sup> It is indicated to treat a number of conditions including heart failure, deem, hyperaldosteronism, adrenal hyperplasia, hypertension, and nephrotic syndrome.<sup class="text-reference-group"><a class="reference-popover-link" data-content="Official drug label" href="#label-reference">Label</a></sup> Off label uses of spironolactone involving its antiandrogenic activity include hirsutism, female pattern hair loss, and adult acne vulgaris.<sup class="text-reference-group"><a class="reference-popover-link" data-content="Kim GK, Del Rosso JQ: Oral Spironolactone in Post-teenage Female Patients with Acne Vulgaris: Practical Considerations for the Clinician Based on Current Data and Clinical Experience. J Clin Aesthet Dermatol. 2012 Mar;5(3):37-50. (PubMed ID 22468178)" href="#reference-A178135">4</a></sup> Spironolactone is also frequently used in medical gender transition.<sup class="text-reference-group"><a class="reference-popover-link" data-content="Millington K, Liu E, Chan YM: The Utility of Potassium Monitoring in Gender-Diverse Adolescents Taking Spironolactone. J Endocr Soc. 2019 Apr 4;3(5):1031-1038. doi: 10.1210/js.2019-00030. eCollection 2019 May 1. (PubMed ID 31065620)" href="#reference-A178138">5</a></sup></p><p>Spironolactone was developed in 1957, marketed in 1959, and approved by the FDA on January 21, 1960.<sup class="text-reference-group"><a class="reference-popover-link" data-content="Menard J: The 45-year story of the development of an anti-aldosterone more specific than spironolactone. Mol Cell Endocrinol. 2004 Mar 31;217(1-2):45-52. doi: 10.1016/j.mce.2003.10.008. (PubMed ID 15134800)" href="#reference-A178243">10</a>,<a class="reference-popover-link" data-content="FDA Approved Drug Products: Spironolactone" href="#reference-L6187">12</a></sup></p>