What are the indications for using spironolactone?

Indications for Spironolactone

Spironolactone is indicated for heart failure with reduced ejection fraction (NYHA Class III-IV), hypertension as add-on therapy, edema from hepatic cirrhosis or nephrotic syndrome, and primary hyperaldosteronism. 1

Primary FDA-Approved Indications

Heart Failure with Reduced Ejection Fraction

Spironolactone is indicated for NYHA Class III-IV heart failure with reduced ejection fraction (LVEF ≤35%) to increase survival, manage edema, and reduce hospitalization. 1 The drug should be added to optimal therapy with beta-blockers and ACE inhibitors (or ARBs, but not both). 2

The evidence base is robust:

• The RALES trial demonstrated a 30% relative risk reduction in death and 35% reduction in heart failure hospitalizations when spironolactone 25-50 mg daily was added to standard therapy 2
• The absolute risk reduction in mortality was 11.4% over 2 years, meaning you need to treat 9 patients for 2 years to prevent 1 death 2
• Benefits extend to patients with heart failure with mildly reduced ejection fraction (HFmrEF, LVEF 41-49%) based on post-hoc analyses 3

Dosing protocol: Start 25 mg once daily, check potassium and creatinine at 1 and 4 weeks, then titrate to target dose of 50 mg daily if tolerated. 2

Hypertension

Spironolactone is indicated as add-on therapy for hypertension not adequately controlled on other agents. 1 This is particularly effective in resistant hypertension—defined as uncontrolled blood pressure despite 3 or more antihypertensive drugs.

In the ASCOT-BPLA substudy, spironolactone (median dose 25 mg) added as fourth-line therapy reduced blood pressure by 21.9/9.5 mmHg in patients with resistant hypertension. 4 The drug was generally well-tolerated with only 6% discontinuing due to adverse effects.

Edema Management

Spironolactone is indicated for edema in two specific settings: 1

• Hepatic cirrhosis: When edema persists despite fluid and sodium restriction
• Nephrotic syndrome: When treatment of underlying disease, fluid/sodium restriction, and other diuretics produce inadequate response

Critical caveat for cirrhosis: Initiate spironolactone in the hospital for patients with hepatic disease, cirrhosis, and ascites due to risk of sudden electrolyte shifts precipitating hepatic encephalopathy and coma. Start with the lowest dose and titrate slowly. 1

Primary Hyperaldosteronism

Spironolactone is indicated for: 1

• Short-term preoperative treatment of primary hyperaldosteronism
• Long-term maintenance therapy for patients with aldosterone-producing adenomas who are not surgical candidates

Emerging and Off-Label Indications

Heart Failure with Preserved Ejection Fraction (HFpEF)

The evidence here is more nuanced. The TOPCAT trial showed mixed results, but post-hoc analysis of patients enrolled in the Americas (where medication adherence was verified) demonstrated benefit with spironolactone in HFpEF (LVEF ≥45%). 5

Consider spironolactone in HFpEF patients with: 5

• LVEF ≥45%
• Elevated BNP or heart failure hospitalization within 1 year
• eGFR >30 mL/min
• Creatinine <2.5 mg/dL
• Potassium <5.0 mEq/L

This requires close monitoring and confirmatory studies are needed. 5

Central Serous Chorioretinopathy (CSC)

Multiple studies demonstrate beneficial effects of spironolactone in persistent or chronic CSC, including improved visual acuity, reduced choroidal thickness, and reduced subretinal fluid. 6 Typical dosing is 25-50 mg daily for 1-3 months. Complete resolution of subretinal fluid occurred in 44-82% of patients depending on CSC subtype. 6

Dermatologic Conditions

Spironolactone has demonstrated efficacy in several dermatologic conditions due to its anti-androgenic effects: 7, 8

• Female acne: Level 1-2 evidence, strength of recommendation B. Typical dose 50-100 mg daily. Can reduce need for antibiotics and isotretinoin. 8
• Female pattern androgenetic alopecia
• Hirsutism
• Hidradenitis suppurativa

Contraindication: Do not use in men due to feminization risk (gynecomastia, decreased libido). 7, 8

Critical Safety Monitoring

Mandatory monitoring requirements: 2

• Check potassium and creatinine before initiation
• Recheck at 1 and 4 weeks after starting or dose changes
• Then at 1,2,3,6 months, and every 6 months thereafter

Management of hyperkalemia: 2

• Potassium 5.5-6.0 mEq/L: Halve dose to 25 mg on alternate days, monitor closely
• Potassium >6.0 mEq/L: Stop immediately, monitor closely, may need specific treatment

Management of worsening renal function: 2

• Creatinine >220 µmol/L (2.5 mg/dL): Halve dose, monitor closely
• Creatinine >310 µmol/L (3.5 mg/dL): Stop immediately, monitor closely

Common pitfalls to avoid: 6

• Concomitant use with potassium supplements, other potassium-sparing diuretics, or combined ACE inhibitor plus ARB—all increase hyperkalemia risk
• NSAIDs increase risk of hyperkalemia and renal dysfunction
• High-potassium salt substitutes
• Elderly patients, diabetics, and those with baseline renal or hepatic dysfunction are at higher risk

Pregnancy: Avoid in pregnancy due to potential feminization of male fetuses through anti-androgenic effects. 1

Gynecomastia: Occurs in approximately 10% of men; switch to eplerenone if this develops. 2