Please check your internet connection and try again.
# Aldactone (spironolactone)
## Overview
Spironolactone is a potassium-sparing diuretic and a competitive aldosterone receptor antagonist. It acts primarily in the distal renal tubules to promote sodium and water excretion while retaining potassium. It also possesses anti-androgen properties.
## Primary Indications
* Heart failure with reduced ejection fraction (HFrEF)
* Primary hyperaldosteronism
* Edema associated with cirrhosis or nephrotic syndrome
* Essential hypertension
* Hirsutism/Acne (off-label)
## Adult Dosing
* **HFrEF:** Initially 25 mg once daily. May increase to 50 mg daily based on tolerance and potassium levels.
* **Hypertension:** 25–100 mg daily in single or divided doses.
* **Edema (Cirrhosis/Nephrotic Syndrome):** 25–200 mg daily. Adjust based on response.
* **Primary Hyperaldosteronism:** 100–400 mg daily in preparation for surgery or long-term management of idiopathic hyperplasia.
## Pediatric Dosing
* **Heart Failure:** 1–3 mg/kg/day divided daily or BID (Max: 50 mg/day).
* **Edema/Hypertension:** 1–3.3 mg/kg/day divided BID (Max: 200 mg/day).
* *Note: Dosing varies significantly by institutional protocol; consult local pediatric guidelines.*
## Dose Adjustments
* **Renal Impairment:** Avoid if eGFR <30 mL/min/1.73m². Use with extreme caution if eGFR 30–50 mL/min/1.73m² due to high risk of hyperkalemia.
* **Hepatic Impairment:** No formal adjustment required, but monitor closely for electrolyte disturbances.
## Contraindications
* Hyperkalemia (generally >5.0 mEq/L)
* Addison’s disease
* Concomitant use of eplerenone
* Anuria
* Acute renal insufficiency or significant renal impairment (CrCl <30 mL/min)
## Adverse Effects
* **Common:** Hyperkalemia, dizziness, fatigue.
* **Endocrine:** Gynecomastia (dose-dependent), breast tenderness, menstrual irregularities, erectile dysfunction (due to anti-androgenic effects).
* **Serious:** Severe hyperkalemia (cardiac arrhythmias), hyponatremia.
## Key Drug Interactions
* **Potassium Supplements/Potassium-Sparing Diuretics:** Massive risk of severe, life-threatening hyperkalemia.
* **ACE Inhibitors/ARBs:** Increases hyperkalemia risk; requires stringent monitoring.
* **NSAIDs:** May reduce natriuretic effect and increase risk of renal impairment/hyperkalemia.
* **Digoxin:** May increase plasma levels of digoxin (reduced clearance).
## Monitoring
* **Potassium:** Baseline, within 1 week of initiation/dose change, then monthly for the first 3 months.
* **Renal Function (SCr/BUN):** Baseline and periodic monitoring determined by stability of potassium.
* **Blood Pressure:** Monitor for orthostasis, especially in elderly patients.
## Clinical Pearls
* **Timing:** Administer in the morning to prevent nocturia.
* **Hyperkalemia Risk:** The risk is highest in patients with decreased renal function and those concurrently taking ACE inhibitors, ARBs, or NSAIDs.
* **Patient Education:** Advise patients to avoid high-potassium foods (e.g., salt substitutes, excessive bananas/potatoes) and to report signs of hyperkalemia (muscle weakness, palpitations, tingling).
* **Cross-reactivity:** If gynecomastia becomes intolerable, consider switching to eplerenone, which is more selective and lacks anti-androgen effects.
***
*Disclaimer: This information is for educational purposes for healthcare professionals. Clinical practice varies; always verify current prescribing information, dosing protocols, and patient-specific factors against institutional guidelines and updated drug monographs.*
