Please check your internet connection and try again.
# Aldactone (spironolactone)
## Overview
Spironolactone is a potassium-sparing diuretic and a synthetic steroid that acts as a competitive antagonist of aldosterone at the distal renal tubules. It promotes sodium and water excretion while retaining potassium.
## Primary Indications
* Heart Failure with reduced ejection fraction (HFrEF)
* Edema associated with hepatic cirrhosis or nephrotic syndrome
* Primary hyperaldosteronism (Conn’s syndrome)
* Essential hypertension
* Off-label: Acne vulgaris, androgenetic alopecia, hirsutism
## Adult Dosing
* **HFrEF (NYHA Class II–IV):** Initial 12.5–25 mg once daily; titrate to target 25–50 mg daily as tolerated.
* **Edema (Cirrhosis/Nephrotic syndrome):** 25–200 mg/day; titrated based on response.
* **Primary Hyperaldosteronism:** 100–400 mg/day pre-operatively; chronic maintenance at the lowest effective dose.
* **Hypertension:** 25–100 mg/day given once or in divided doses.
## Pediatric Dosing
*Dosing is highly dependent on institutional protocol.*
* **Heart Failure:** 1–3 mg/kg/day divided once or twice daily (Max: 50 mg/day).
* **Diuretic (General):** 1–3.3 mg/kg/day divided every 12–24 hours (Max: 9 mg/kg/day or 200 mg/day).
## Dose Adjustments
* **Renal Impairment:** Avoid or exercise extreme caution in patients with CrCl <30 mL/min due to high risk of hyperkalemia.
* **Hepatic Impairment:** Generally safe, but monitor for fluid/electrolyte shifts during rapid diuresis.
## Contraindications
* Anuria
* Acute renal insufficiency or significant renal impairment (CrCl <30 mL/min)
* Addison’s disease
* Hyperkalemia (serum potassium >5.0–5.5 mEq/L)
* Concomitant use with eplerenone or potassium supplements
## Adverse Effects
* **Hyperkalemia:** Life-threatening potential; primary dose-limiting factor.
* **Endocrine:** Gynecomastia, breast tenderness, impotence, menstrual irregularities (attributable to anti-androgen activity).
* **Gastrointestinal:** Gastritis, diarrhea, nausea.
* **Neurological:** Dizziness, headache, lethargy.
## Key Drug Interactions
* **Potassium-Sparing Agents/Supplements:** High risk of severe hyperkalemia.
* **ACE Inhibitors/ARBs/Aliskiren:** Synergistic risk of hyperkalemia.
* **Lithium:** May reduce renal clearance and increase toxicity risk.
* **NSAIDs:** May diminish the diuretic effect and increase risk of renal impairment/hyperkalemia.
* **Digoxin:** May interfere with assays and decrease clearance.
## Monitoring
* **Potassium:** Baseline, within 1 week of initiation/titration, and periodically thereafter (more frequently in CKD).
* **Renal Function:** Baseline and periodic Serum Creatinine/BUN.
* **Blood Pressure:** Monitor for orthostasis, especially at initiation.
* **Fluid Status:** Weight, edema severity, and intake/output.
## Clinical Pearls
* **Anti-androgen effects:** If gynecomastia occurs, switching to eplerenone (which is more selective for the mineralocorticoid receptor) should be considered.
* **Time to effect:** Diuretic effect may take up to 3 days to manifest; anti-hypertensive effect in HFrEF may take weeks.
* **Take consistently:** Take with or without food, but be consistent to minimize variability in absorption.
***
**Educational Disclaimer:** This information is for educational purposes only. Clinical practice guidelines change frequently. Always verify current prescribing information, institutional protocols, and patient-specific contraindications via reliable primary resources (e.g., Lexicomp, UpToDate, or the manufacturer’s product insert) before prescribing or administering medication.
