Uses

What is spironolactone used for?

Spironolactone is commonly used for the following conditions.

  • To lower blood pressure (hypertension)
  • To help lower the risk of death and hospitalization in people with heart failure, a condition where the heart is not pumping blood as well as it should
  • To help reduce fluid build up in people who have liver disease such as cirrhosis or a kidney disease called nephrotic syndrome
  • To help people who produce too much of the hormone aldosterone, which is usually caused by a problem with the functioning of the adrenal glands

Spironolactone may also be used for other conditions as determined by your healthcare provider.

How does spironolactone work (mechanism of action)?

Spironolactone works by blocking a hormone called aldosterone in your body. Aldosterone causes your body to retain sodium and water, which can increase blood pressure. Blocking aldosterone helps decrease the amount of sodium and water the body retains.

How is spironolactone supplied (dosage forms)?

Spironolactone is available in the following dosage forms that are taken by mouth.

  • 25 mg oral tablets
  • 50 mg oral tablets
  • 100 mg oral tablets
  • 25 mg/5 mL oral suspension

How should I store spironolactone?

Spironolactone should be stored at room  temperature, between 68 and 77 degrees F (20 to 25 C).  It can be exposed to temperatures between 59 and 86 F (15 to 30 C), for shorter periods of time, such as when transporting it.  Store in a cool, dry place.

Side Effects

What are the most common side effects of spironolactone?

The most common side effects of spironolactone are listed below. Tell your healthcare provider if you have any of these side effects that bother you.

  • Low blood pressure (see below)
  • High potassium level (see below)
  • Enlarged breasts in men (gynecomastia) 
  • Dizziness

There may be other side effects of spironolactone that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of spironolactone?

While less common, the most serious side effects of spironolactone are described below, along with what to do if they happen.

Severe Allergic Reactions. Spironolactone may cause allergic reactions, which can be serious. Stop using spironolactone and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Low Blood Pressure (Hypotension) with Worsening Kidney Function. Water loss from spironolactone may cause low blood pressure (hypotension) and dehydration, especially in people with low levels of fluid or sodium. This can happen especially in people taking other medications that affect the level of fluid in the body, such as a diuretic.  Both hypotension and dehydration may lead to problems that are more serious than light-headedness. Poor blood flow to important organs such as your kidneys can occur, especially if you are elderly. Drink enough water to stay hydrated, especially if you have excess sweating, vomiting, or diarrhea. Get out of bed or from a seated position slowly.  If you feel faint or dizzy, lie down.  Tell your healthcare provider right away if you have any of the following symptoms.

  • Dizziness, feeling lightheaded, or fainting
  • Confusion
  • Feeling weak or tired
  • Confusion
  • Reduced need to pee
  • Increased thirst
  • Dark or strong-smelling pee
  • Dry mouth
  • Sunken eyes
  • Headache
  • Fast heartbeat

High Potassium Level (Hyperkalemia). Spironolactone can cause a high potassium level (hyperkalemia) which can be serious and lead to death.  Your healthcare provider will check your potassium levels, especially if you take certain other medications. It is important that you keep all appointments and follow all recommendations to get your blood checked.  Call your healthcare provider right away if you have any of the following symptoms of a high potassium level.

  • Muscle weakness or unusual tiredness
  • Slow heartbeat or feeling of skipped heartbeats
  • Nausea and vomiting
  • Trouble breathing
  • Abnormal heart rhythm

Electrolyte Changes and Increased Blood Sugar. Spironolactone may increase your blood sugar (glucose) levels and cause changes to the levels of certain minerals in your body, called electrolytes. For example, it may cause low sodium levels (hyponatremia), low magnesium levels (hypomagnesemia), low calcium levels (hypocalcemia), or low chloride levels (hypochloremia). These changes can be serious. Your healthcare provider will do bloodwork to check your glucose and electrolyte levels, especially if you take certain other medicines. Keep your appointments to have your blood checked. Call your healthcare provider if you have any of the following symptoms.

  • Weakness
  • Unusual tiredness
  • Muscle cramps or twitching
  • Constipation
  • Nausea, vomiting, or loss of appetite
  • Dizziness
  • Restlessness or irritability
  • Difficulty breathing
  • Confusion or decreased alertness
  • Abnormal heart rhythm
  • Seizures

Warnings & Precautions

Who should not use spironolactone?

Allergies to Ingredients. People who are allergic to any of the following should not use spironolactone.

  • Aldactone
  • Carospir
  • Spironolactone
  • Any of the ingredients in the specific product dispensed

High Potassium Levels (Hyperkalemia). Patients who have very high potassium levels in the blood should not start or use spironolactone until the potassium levels return to normal.  Your doctor may monitor your potassium levels with a blood test after starting or while on spironolactone.  

Addison’s Disease. Spironolactone should not be used in people who have a condition where your body’s adrenal glands stop making as much cortisol (the stress hormone) as they should, also known as Addisons’ Disease.

Drug Interactions. Spironolactone should not be used while you are taking certain other medicines.  Before taking spironolactone, tell your healthcare provider about any other prescriptions or over-the-counter medicines, vitamins/minerals, herbal products, or other supplements you are taking.  See the interactions section for more details.  

What should I know about spironolactone before using it?

Do not take spironolactone unless it has been prescribed to you by a healthcare provider. Take it as prescribed.

Do not share spironolactone with other people, even if they have the same condition as you. It may harm them.

Keep spironolactone out of the reach of children.

Spironolactone can affect your alertness or coordination. Do not drive or do other activities that require alertness or coordination until you know how spironolactone can affect you.  

You may take spironolactone with or without food.  You should try to take it the same way every time.

A liquid form of this medicine is available.  If you take this form, shake the liquid well before each use. Use an accurate measuring device to measure your dose. A household spoon is not an accurate measuring device and may cause you to take the wrong dose. Ask your pharmacist to recommend an appropriate measuring device.

What should I tell my healthcare provider before using spironolactone?

Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if spironolactone is right for you.

In particular, make sure that you tell your healthcare provider if you have any of the following.

  • Liver problems
  • Kidney problems
  • Electrolyte imbalance, such as high or low levels of sodium or potassium
  • Diabetes
  • Gout

Pregnancy. Spironolactone may harm an unborn baby. Tell your healthcare provider if you are or plan to become pregnant. Your healthcare provider will advise you if you should take spironolactone while you are pregnant or trying to get pregnant. 

Breastfeeding. Spironolactone does not pass into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed. Your healthcare provider will advise you if you should take spironolactone while breastfeeding.

Interactions

Does spironolactone interact with foods or drinks?

Spironolactone can interact with foods and drinks that are high in potassium. Because spironolactone increases potassium levels, your doctor may suggest avoiding foods or drinks that are high in potassium.

It is unknown if drinking alcohol will affect spironolactone. The risk of dizziness may be increased if you drink alcohol while taking spironolactone. It is best to limit the amount of alcohol you drink.

Does spironolactone interact with other medicines (drug interactions)?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. 

In particular, make sure you discuss if you are using any of the following before taking spironolactone.

  • Non-steroidal anti-inflammatory drugs (NSAIDS) such as ibuprofen, naproxen and others.  These are often contained in many prescription and OTC products for pain, swelling, and fever
  • An angiotensin-converting enzyme (ACE) inhibitor which is a medicine for blood pressure, heart failure, and certain kidney problems
  • Angiotensin receptor blockers (ARB) which is a medicine for blood pressure, heart failure, and certain kidney problems
  • A supplement or salt-substitute containing potassium 
  • A diuretic, also called a water pill, which is a medicine used to reduce edema (fluid retention) and blood pressure
  • Eplerenone, a medicine used for heart failure
  • Any medicine for high blood pressure
  • Heparin, which is a medicine to help prevent the blood from clotting
  • Lithium, which is a medicine for certain mental health conditions
  • Digoxin, which is a medicine used for heart failure
  • Aspirin, which is a medicine used in a variety of conditions
  • Cholestyramine, a medicine used to treat high cholesterol and some intestinal conditions
  • Abiraterone, a hormone therapy drug

Spironolactone may alter the blood levels of some other medicines. Tell your healthcare provider about all medicines that you take or have recently taken.

Does Spironolactone interact with other drugs you are taking?
Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much spironolactone?

If you or someone else has used too much spironolactone, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of spironolactone?

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.

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