Generic name: spironolactone [ spir-ON-oh-LAK-tone ]
Other brand names of spironolactone include Aldactone, CaroSpir
Drug classes: Aldosterone receptor antagonists, Potassium-sparing diuretics

Medically reviewed by Drugs.com on Mar 4, 2025. Written by Cerner Multum.

What is CaroSpir?

CaroSpir is a potassium-sparing diuretic (water pill) that prevents your body from absorbing too much salt and keeps your potassium levels from getting too low.

CaroSpir is used to treat heart failure, high blood pressure (hypertension), or hypokalemia (low potassium levels in the blood).

CaroSpir also treats fluid retention (edema) in people with congestive heart failure, cirrhosis of the liver, or a kidney disorder called nephrotic syndrome.

CaroSpir is also used to diagnose or treat a condition in which you have too much aldosterone in your body. Aldosterone is a hormone produced by your adrenal glands to help regulate the salt and water balance in your body.

CaroSpir may also be used for purposes not listed in this medication guide.

CaroSpir side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

CaroSpir may cause serious side effects. Call your doctor at once if you have:

• a light-headed feeling, like you might pass out;

• little or no urination;

• high potassium level--nausea, weakness, tingly feeling, chest pain, irregular heartbeats, loss of movement; o

• signs of other electrolyte imbalances--increased thirst or urination, confusion, vomiting, muscle pain, slurred speech, severe weakness, numbness, loss of coordination, feeling unsteady.

Common side effects of CaroSpir may include:

• breast swelling or tenderness.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

Warnings

You should not use CaroSpir if you Addison's disease, high levels of potassium in your blood, if you are unable to urinate, or if you are also taking eplerenone.

Before taking this medicine

You should not use CaroSpir if you are allergic to it, or if you have:

• Addison's disease (an adrenal gland disorder);

• high levels of potassium in your blood (hyperkalemia);

• if you are unable to urinate; or

• if you are also taking eplerenone.

Tell your doctor if you have ever had:

• an electrolyte imbalance (such as low levels of calcium, magnesium, or sodium in your blood);

• kidney disease;

• liver disease; or

• heart disease.

Tell your doctor if you are pregnant or plan to become pregnant. Having congestive heart failure, cirrhosis, or uncontrolled high blood pressure during pregnancy may lead to medical problems in the mother or the baby. Your doctor should decide whether you take CaroSpir if you are pregnant.

It may not be safe to breastfeed while using CaroSpir. Ask your doctor about any risk.

How should I take CaroSpir?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Do not share this medicine with another person, even if they have the same symptoms you have.

You may take CaroSpir with or without food, but take it the same way each time.

You will need frequent medical tests.

This medicine can affect the results of certain medical tests. Tell any doctor who treats you that you are using CaroSpir.

If you need surgery, tell your surgeon you currently use this medicine. You may need to stop for a short time.

If you are being treated for high blood pressure, keep using this medication even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medication for the rest of your life.

Store at room temperature away from heat, light, and moisture.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking CaroSpir?

Drinking alcohol can increase certain side effects.

Do not use potassium supplements or salt substitutes, unless your doctor has told you to.

Avoid a diet high in salt. Too much salt will cause your body to retain water and can make this medication less effective.

Avoid driving or hazardous activity until you know how CaroSpir will affect you. Your reactions could be impaired. Avoid getting up too fast from a sitting or lying position, or you may feel dizzy.

What other drugs will affect CaroSpir?

Using CaroSpir with other drugs that make you dizzy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety, depression, or seizures.

Tell your doctor about all your other medicines, especially:

• colchicine;

• digoxin;

• lithium;

• loperamide;

• trimethoprim;

• heart or blood pressure medicine (especially another diuretic);

• medicine to prevent a blood clot; or

• NSAIDs (nonsteroidal anti-inflammatory drugs)--aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others.

This list is not complete. Other drugs may affect CaroSpir, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Popular FAQ

More FAQ

• What is the strength of CaroSpir (spironolactone) oral suspension?

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

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