Inspra

Generic name: eplerenone
Drug classes: Aldosterone receptor antagonists, Potassium-sparing diuretics

Medically reviewed by A Ras MD.

What is Inspra used for?

Inspra is a prescription medicine that is used to treat high blood pressure. It is used to help the heart function after a heart attack. Inspra may be given to you for other reasons.

Description

INSPRA contains eplerenone, a blocker of aldosterone binding at the mineralocorticoid receptor.

Eplerenone is chemically described as Pregn-4-ene-7,21-dicarboxylic acid, 9,11-epoxy-17-hydroxy-3-oxo-, γ-lactone, methyl ester, (7α,11α,17α)-. Its empirical formula is C24H30O6 and it has a molecular weight of 414.50. The structural formula of eplerenone is represented below:

Eplerenone is an odorless, white to off-white crystalline powder. It is very slightly soluble in water, with its solubility essentially pH-independent. The octanol/water partition coefficient of eplerenone is approximately 7.1 at pH 7.0.

INSPRA tablets for oral administration contain 25 mg or 50 mg of eplerenone and the following inactive ingredients: lactose, microcrystalline cellulose, croscarmellose sodium, hypromellose, sodium lauryl sulfate, talc, magnesium stearate, titanium dioxide, polyethylene glycol, polysorbate 80, and iron oxide yellow and iron oxide red.

Mechanism of Action

Eplerenone binds to the mineralocorticoid receptor and blocks the binding of aldosterone, a component of the renin-angiotensin-aldosterone-system (RAAS). Aldosterone synthesis, which occurs primarily in the adrenal gland, is modulated by multiple factors, including angiotensin II and non-RAAS mediators such as adrenocorticotropic hormone (ACTH) and potassium. Aldosterone binds to mineralocorticoid receptors in both epithelial (e.g., kidney) and nonepithelial (e.g., heart, blood vessels, and brain) tissues and increases blood pressure through induction of sodium reabsorption and possibly other mechanisms.

Eplerenone has been shown to produce sustained increases in plasma renin and serum aldosterone, consistent with inhibition of the negative regulatory feedback of aldosterone on renin secretion. The resulting increased plasma renin activity and aldosterone circulating levels do not overcome the effects of eplerenone.

Eplerenone selectively binds to human mineralocorticoid receptors relative to its binding to recombinant human glucocorticoid, progesterone, and androgen receptors.

Before taking Inspra, tell your doctor:

If you are allergic to Inspra; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
If you have any of these health problems: High blood sugar (diabetes) with protein in urine, high potassium levels, or kidney disease.
If you are taking any of these drugs: Clarithromycin, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, or troleandomycin.
If you are taking any of these drugs: Amiloride, potassium, spironolactone, or triamterene.

This is not a list of all drugs or health problems that interact with this medicine.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take Inspra with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Inspra?

Tell all of your health care providers that you take Inspra. This includes your doctors, nurses, pharmacists, and dentists.
Check your blood pressure as you have been told.
Have blood work checked as you have been told by the doctor. Talk with the doctor.
It may take several weeks to see the full effects.
Talk with your doctor before using a salt substitute.
If you are taking Inspra and have high blood pressure, talk with your doctor before using OTC products that may raise blood pressure. These include cough or cold drugs, diet pills, stimulants, ibuprofen or like products, and some natural products or aids.
If you are 65 or older, use Inspra with care. You could have more side effects.
This medicine may affect being able to father a child. Talk with the doctor.
Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using Inspra while you are pregnant.
Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

How is Inspra best taken?

Use Inspra as ordered by your doctor. Read all information given to you. Follow all instructions closely.

Take with or without food.
Keep taking Inspra as you have been told by your doctor or other health care provider, even if you feel well.

What do I do if I miss a dose?

Take a missed dose as soon as you think about it.
If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
Do not take 2 doses at the same time or extra doses.

What are the side effects of Inspra that I need to call my doctor about immediately?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
Signs of high potassium levels like a heartbeat that does not feel normal; feeling confused; feeling weak, lightheaded, or dizzy; feeling like passing out; numbness or tingling; or shortness of breath.
Diarrhea.
Throwing up.
Chest pain or pressure or a fast heartbeat.
Swelling in the arms or legs.
Not able to pass urine or change in how much urine is passed.

What are some other side effects of Inspra?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if you have any side effects that bother you or do not go away.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If overdose is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Inspra?

Store at room temperature.
Store in a dry place. Do not store in a bathroom.
Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.