Eplerenone Tablets

Mechanism

Eplerenone selectively blocks aldosterone at mineralocorticoid receptors in the kidney, heart, and vasculature. This reduces sodium reabsorption and water retention, lowers blood pressure, and prevents cardiac remodeling.

Pharmacokinetics

• Absorption: Oral bioavailability ~70%; peak plasma concentration reached in 1.5–2 hours; food does not significantly affect absorption.
• Distribution: ~50% protein bound; volume of distribution ~50 L; widely distributed to kidney, heart, and vascular tissue.
• Metabolism: Extensively metabolized in the liver via CYP3A4; metabolites are inactive.
• Excretion: ~67% excreted via urine (mainly metabolites), ~32% via feces; negligible unchanged drug in urine.
• Half-life: ~4–6 hours; steady-state achieved within 2 days of dosing.
• Special Populations: Clearance reduced in renal impairment and elderly patients; dose adjustment required in hepatic impairment.

Side Effects

• Dizziness
• Fatigue
• Hyperkalemia (serious)
• Breast tenderness
• Kidney dysfunction

Contraindication

• Severe renal impairment
• Hyperkalemia
• Concomitant use with strong CYP3A4 inhibitors

Interaction

• ACE inhibitors/ARBs (increased risk of hyperkalemia)
• Potassium supplements or potassium-sparing diuretics
• NSAIDs (reduced efficacy, increased renal risk)
• Strong CYP3A4 inhibitors (ketoconazole, ritonavir, clarithromycin)

Warning and Precautions

• Monitor serum potassium and renal function regularly
• Use under medical supervision only
• Caution in elderly patients

Dosage

As directed by the Physician.