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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Limited Use [what does this mean?]
Generic drug name: eplerenone (e PLARE e none)
Brand name(s): INSPRA
GENERIC: not available FAMILY: Potassium-sparing Diuretics
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

Eplerenone increased fetal resorptions in animal studies.  Tell your doctor if you are pregnant or thinking of becoming pregnant before you use this drug.

Breast-feeding Warning

Eplerenone was excreted in animal milk.  It is likely that this drug is also excreted in human milk.  Because of the potential for serious adverse effetcs in nursing infants, you should not use this drug while nursing.

Facts About This Drug [top]

Eplerenone (INSPRA) was initially approved by the Food and Drug Administration (FDA) in September 2002 to treat high blood pressure, but the drug’s manufacturer chose not to put the product on the market at that time. Rather, the company opted to wait to market eplerenone until it had also gained approval for improving the survival of stable patients with a damaged left ventricle (large chamber of the heart) and evidence of congestive heart failure after a heart attack. This approval was...

Eplerenone (INSPRA) was initially approved by the Food and Drug Administration (FDA) in September 2002 to treat high blood pressure, but the drug’s manufacturer chose not to put the product on the market at that time. Rather, the company opted to wait to market eplerenone until it had also gained approval for improving the survival of stable patients with a damaged left ventricle (large chamber of the heart) and evidence of congestive heart failure after a heart attack. This approval was granted in October 2003.  In 2008, the drug was also approved for hypertension in pediatric patients.[1]

The additional approved uses for the drug allow it to be legally advertised as more than just another high blood pressure-lowering drug. This is important because the marketplace for high blood pressure-lowering drugs is crowded, with dozens of competing agents, and eplerenone is not very distinguished among them – the drug is only moderately effective in this regard.

Eplerenone belongs to the family of water pills, or diuretics, known as potassium-sparing diuretics and is most similar to an older drug called spironolactone (ALDACTONE).

Side effects

One of the major concerns of potassium-sparing diuretics such as spironolactone and eplerenone is that they can lead to dangerously high levels of potassium (hyperkalemia) that can potentially cause death in the elderly and in persons with poor kidney function. 

The professional product labeling (package insert) for eplerenone states: “The principal risk of INSPRA is hyperkalemia. Hyperkalemia can cause serious, sometimes fatal, arrhythmias (heart rhythm disturbances).”[2] 

Studies say...

Researchers are consistently unimpressed by the effectiveness of epleronone.   

As mentioned above, eplerenone is not much of a high blood pressure-lowering drug. A senior FDA scientist wrote in a September 27, 2002, memo about the drug’s effectiveness and the risk of increasing potassium blood levels: “We have no reason to think eplerenone is anything but a garden-variety antihypertensive [blood-pressure-lowering drug] of ordinary effectiveness; i.e., there is no reason to accept increased risk [elevated potassium levels] compared to alternative agents.”[3]

The FDA reviewed a number of clinical trials in which eplerenone was compared directly to other high blood-pressure-lowering drugs. Eplerenone was found comparable to spironolactone, the thiazide diuretic hydrochlorothiazide (ESIDRIX, HYDRODIURIL, MICROZIDE), and the angiotensin converting enzyme (ACE) inhibitor enalapril (VASOTEC). Nothing special was found with eplerenone. 

The Medical Letter on Drugs and Therapeutics, a publication we frequently cite because of its reputation as an independent source of drug information, concluded its review of eplerenone by saying the drug is “modestly effective for treatment of hypertension.”[4] 

A large clinical trial found the addition of the drug to the best standard therapy improved the survival of patients who had a heart attack complicated by a damaged left ventricle and heart failure.[5] 

This study found that death from all causes was lower in those taking eplerenone compared to patients receiving a placebo. In the placebo group, 16.7 percent of patients died. This was decreased to 14.4 percent in the eplerenone group. The absolute difference in risk of dying between the two groups was 2.3 percent. In other words, 44 patients need to be treated with eplerenone for 16 months to prevent one death.

The downside of eplerenone, as alluded to above, is the risk of developing a serious elevation in blood potassium level, or hyperkalemia. In those taking eplerenone, 5.5 percent of the patients experienced a serious elevation in their potassium blood level, whereas only 3.9 percent of those given placebo, had a serious episode of hyperkalemia. This is an absolute difference of 1.6 percent in risk of developing hyperkalemia with eplerenone. That means 63 patients taking eplerenone that must be treated for over 16 months before there is one case of hyperkalemia that develops can be calculated - this is known as the number needed to harm. 

On its face, it appears that the benefits of eplerenone outweigh the risk of hyperkalemia, and it is true that not all cases of hyperkalemia result in death. However, although the patients in this study were carefully watched by the researchers, this is not always the case in the everyday practice of medicine. In addition, patients were excluded from entering the study if they were taking a potassium-sparing diuretic or had decreased kidney function, both of which increase the risk of hyperkalemia. If, for example, once eplerenone is widely prescribed and the percentage of patients who develop hyperkalemia increases by a modest 1.0 percent, from 5.5 percent to 6.5 percent, the number needed to harm drops to 38 patients on eplerenone for 16 months.

The May 2012 issue of Worst Pills, Best Pills News highlighted a recent British Medical Journal (BMJ) study indicating that patients taking several types of commonly used antihypertensive medications are at increased risk of developing gout, a type of arthritis.

The BMJ study also showed that a small number of other antihypertensive drugs appear to have the opposite effect, decreasing the risk of gout.

All patients should be informed of the risk of gout with diuretics, beta-blockers, angiotensin-converting enzyme inhibitors (ACE inhibitors) and non-lorsartan angiotensin II receptor blockers (ARBs) when starting these medications or whenever the dose of the medications is increased [6].

The April 2013 issue of Worst Pills, Best Pills News discusses another recent BMJ study. This study suggests that an increased risk of acute kidney injury (AKI) is associated with combining nonsteroidal anti-inflammatory drugs (NSAIDs) with two antihypertensive drugs: a diuretic plus either an ACE inhibitor or an ARB. The risk was found to be highest during the first 30 days of starting an NSAID in patients who also are already taking a diuretic plus an ACE inhibitor or an ARB.

The study found that patients currently using a triple-therapy combination — a diuretic, an ACE inhibitor or an ARB, and an NSAID — have a 31 percent greater risk of developing AKI compared with current users of a diuretic plus an ACE inhibitor or an ARB without an NSAID.[7]

Before You Use This Drug [top]

Do not use if you have or have had:

  • allergies
  • diabetes
  • kidney problems
  • microalbuminuria (albumin protein in the urine)
  • potassium that is high (hyperkalemia)
  • pregnancy or are breast-feeding

Tell your doctor if you have or have had:

  • liver disease
  • allergy to eplerenone

Tell your doctor about any other drugs you take, including antifungals, diuretics, potassium, herbs, over-the-counter medications, and vitamins.

When You Use This Drug [top]

  • Do not take any potassium supplements or use salt substitutes containing potassium.
  • Limit intake of sodium salts.
  • Be aware that eplerenone may cause dizziness.
  • Tell any doctor, dentist, emergency help, or pharmacist you see that you take this drug.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as possible, unless it is almost time for the next dose.   Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Swallow tablet(s) with or without food.
  • Do not break, chew, or crush this drug.
  • Avoid taking with grapefruit juice.
  • Store tablets at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

ACCUPRIL, ACCURETIC, ACEON, ADVIL, ALDACTONE, ALEVE, ALTACE, amiloride, ANSAID, benazepril, BIAXIN, CALAN, CAPOTEN, CAPOZIDE, captopril, cilazapril, clarithromycin, CLINORIL, COZAAR, DAYPRO, diclofenac, DIFLUCAN, diflunisal, DIOVAN, DIOVAN HCT, DOLOBID, DYAZIDE, DYRENIUM, EES, EFFER-K, E-MYCIN, enalapril, ERYBID, ERYC, ERYPED, ERY-TAB, ERYTHROCIN, ERYTHROCOT, erythromycin, ESKALITH, etodolac, fenoprofen, floctafenine, fluconazole, flurbiprofen, fosinopril, GLU-K, grapefruit juice, hypercium, HYZAAR, ibuprofen, ILOSONE, ILOTYCIN, INDOCIN, indomethacin, INHIBASE, INVIRASE, ISOPTIN, itraconazole, K1CARE, KALETRA, KAON-CL, KAYLIXIR, K-DUR, K-ELECTROLYTE, ketoconazole, ketoprofen, KLEASE, KLOR-CON, KLORVESS, K-LYTE, K-NORM, KOLYUM, K-TABS, lisinopril, lithium, LITHOBID, LODINE, losartan, LOTENSIN, LOTENSIN HCT, MAVIK, MAXZIDE, meclofenamate, MECLOMEN, mefanamicacid, meloxicam, MICRO-K, MIDAMOR, MOBIC, MODURETIC, moexipril, MONOPRIL, MOTRIN, MY-E, nambutenone, NAPROSYN, naproxen, nefazodone, nelfinavir, NIZORAL, NORVIR, ORUDIS, oxaprozin, PCE, perindopril, piroxicam, PONSTEL, potassium salt substitutes that contain potassium, PRINIVIL, PRINZIDE, quinapril, ramipril, RELAFEN, ritonavir, saquinavir, SERZONE, spironolactone, SPORANOX, SPRIOZIDE, St. John’s wort, sulindac, TAO, TEN-K, tenoxicam, tiaprofenic acid, TOLECTIN, tolmetin, trandolapril, triamterene, TRI-K, troleandomycin, TWIN-K, UNIRETIC, UNIVASC, valsartan, VASERETIC, VASOTEC, verapamil, VIRACEPT, VOLTAREN, WINTROCIN, ZESTORETIC, ZESTRIL.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • cloudy urine
  • high cholesterol or triglyceride levels in the blood
  • chest pain or discomfort
  • dizziness
  • confusion
  • nervousness
  • weakness or heaviness of legs
  • arm, back, or jaw pain
  • chest tightness
  • fast or irregular heartbeat
  • shortness of breath
  • sweating
  • nausea or vomiting
  • headache
  • abdominal pain

Call your doctor if these symptoms continue:

  • stomach pain
  • breast enlargement in men
  • breast swelling or pain in men or women
  • cough
  • chills
  • diarrhea
  • fever
  • fatigue
  • flulike symptoms
  • headache
  • menstrual changes or abnormal vaginal bleeding
  • joint pain
  • loss of appetite
  • muscle aches and pains

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • blood pressure
  • blood test for potassium
  • kidney function tests such as creatinine clearance

last reviewed March 31, 2024