An oral diuretic used to treat high blood pressure, heart failure, and fluid retention.
Spironolactone is an aldosterone antagonist indicated for: The treatment of NYHA Class III-IV heart failure and reduced ejection fraction to increase survival, manage edema, and to reduce the need for hospitalization for heart failure ( 1.1 ). Use as an add-on therapy for the treatment of hypertension, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions ( 1.2 ). The management of edema in adult patients who are cirrhotic when edema is not responsive to fluid and sodium restrictions and in the setting of nephrotic syndrome when treatment of the underlying disease, restriction of fluid and sodium intake, and the use of other diuretics produce an inadequate response ( 1.3 ). Treatment of primary hyperaldosteronism for: ( 1.4 ) Short-term preoperative treatment Long-term maintenance for p…
12.1 Mechanism of Action Spironolactone and its active metabolites are specific pharmacologic antagonists of aldosterone, acting primarily through competitive binding of receptors at the aldosterone-dependent sodium-potassium exchange site in the distal convoluted renal tubule. Spironolactone causes increased amounts of sodium and water to be excreted, while potassium is retained. Spironolactone acts both as a diuretic and as an antihypertensive drug by this mechanism. It may be given alone or with other diuretic agents that act more proximally in the renal tubule.
Sources: drug label, approval and manufacturer data from the U.S. FDA via the openFDA API; shortage status from the FDA Drug Shortage Database. This page is a plain-English summary for general information and is not medical advice. It is not exhaustive and may not reflect the latest label — always consult the official prescribing information and your clinician or pharmacist. Brand availability, indications and approvals differ between the US, EU/Ireland (EMA/HPRA) and other regions.