Eplerenone is an aldosterone antagonist type of potassium-sparing diuretic that is used to treat chronic heart failure and high blood pressure, particularly for patients with resistant hypertension due to elevated aldosterone.
Trade names Inspra
Pregnancy category AU: B3
Routes of administration By mouth
Bioavailability ~70%
Protein binding ~50% (33–60%)
Metabolism Liver (CYP3A4)
Elimination half-life 4–6 hours
Excretion Urine (67%), feces (32%)
Eplerenone is a steroidal antimineralocorticoid of the spirolactone group and a selective aldosterone receptor antagonist.
It is more selective than spironolactone at the mineralocorticoid receptor relative to binding at androgen, progestogen, glucocorticoid, or estrogen receptors.
Eplerenone reduces risk of death in patients with heart failure,
particularly in patients with recent myocardial infarction.
It lowers blood pressure in patients with primary hypertension.
Eplerenone also reduces arterial stiffness and vascular endothelial dysfunction.
It is safe and effective for reducing blood pressure, particularly in persons with resistant hypertension due to hyperaldosteronism.
Eplerenone is often prescribed for people with central serous chorioretinopathy.
Common adverse drug reactions: hyperkalemia, hypotension, dizziness, and reduced renal clearance.
It may have a lower incidence than spironolactone of sexual side effects such as feminization, gynecomastia, impotence, low sex drive and reduction of size of male genitalia.
Eplerenone is primarily metabolized by the cytochrome P450 enzyme CYP3A4, with the potential exists for adverse drug interactions with other drugs that induce or inhibit CYP3A4.
The concomitant use of the CYP3A4 potent inhibitors ketoconazole and itraconazole is contraindicated.
Other CYP3A4 inhibitors including erythromycin, saquinavir, and verapamil should be used with caution.
Other drugs that increase potassium concentrations may increase the risk of hyperkalemia associated with eplerenone therapy, including salt substitutes, potassium supplements and other potassium-sparing diuretics.
Eplerenone is an antimineralocorticoid, or an antagonist of the mineralocorticoid receptor.
The drug controls high blood pressure by blocking the binding of aldosterone to the mineralocorticoid receptor (MR) in epithelial tissues, such as the kidney.
Blocking the action of aldosterone decreases blood volume and lowers blood pressure.
Eplerenone has 10- to 20-fold lower affinity for the mineralocorticoid recepto relative to spironolactone, and is less potent as an antimineralocorticoid.
In contrast to spironolactone, eplerenone has little affinity for the androgen, progesterone, and glucocorticoid receptors.
Eplerenone differs from spironolactone by its extensive metabolism, with a short half-life and inactive metabolites.
It is about 50 to 75% as potent as spironolactone as an antimineralocorticoid: 25 mg/day spironolactone may be equivalent to approximately 50 mg/day eplerenone.