OverviewDosageSide EffectsInteractionsHalf-Life

Medical providers sometimes prescribe spironolactone for weight loss off-label. However, there is not enough research to determine the effectiveness of this medication for weight loss. Many people believe that this medication results in weight loss because spironolactone is a diuretic, which means it helps reduce fluid retention. While using this medication may result in some weight loss, this is usually short-term loss until fluid levels go back to their normal level. In other words, this drug does not result in fat loss, but rather temporary “water weight.”

Spironolactone for Weight Loss — Dosage

Spironolactone is in the potassium-sparing diuretic drug class, or a medication that promotes urination while encouraging potassium retention. As a diuretic, this medication might help reduce weight associated with water retention.

The dosage that individuals should take for weight loss can vary based on certain factors, so it’s best to discuss this option with a medical provider. Dosages for other uses, such as heart failure, edema, or hypertension (high blood pressure), can range from 25 mg to 50 mg, 100 mg, or 200 mg per day.

Side Effects

For more information, please visit our page on spironolactone side effects.


Does spironolactone cause weight loss or gain?

Some individuals who have taken spironolactone have reported gaining weight, but more research is needed to understand if this medication directly leads to weight gain. Spironolactone might lead to short-term weight loss due to decreased water retention. However, weight levels can go back to normal as fluid returns.

What foods should be avoided when taking spironolactone?

When taking spironolactone, it is important to avoid consuming foods that have high amounts of sodium or salt, such as processed foods. Eating these foods can make it more difficult for spironolactone to work effectively. Since this medication can cause an increase in potassium levels, individuals should avoid taking potassium supplements or consuming high amounts of potassium in their daily diet.

Does spironolactone make your breasts bigger?

Spironolactone might cause a condition known as gynecomastia, in which male breasts become larger. In studies involving men with heart failure, around 9 percent developed this condition after taking 26 mg of spironolactone; the risk of this condition becomes higher as dosage increases. Breast enlargement, which is generally reversible, can occur anywhere from within a month to more than a year.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.


Generic Name: Spironolactone


Class: Aldosterone antagonist, potassium-sparing diuretic

Availability: Prescription

Molecular Formula: C24H32O4S

Substance UNII: 27O7W4T232

What is Spironolactone?

Spironolactone is an aldosterone antagonist and potassium-sparing diuretic. It is often sold under the trade names Aldactone and CaroSpir.

What is Spironolactone Used For?

The FDA has approved spironolactone for the treatment of heart failure, hypertension, edema associated with nephrotic syndrome or hepatic cirrhosis, and primary hyperaldosteronism. People also sometimes use it to treat acne or to promote weight loss.

How Does Spironolactone Work?

Spironolactone works by blocking the activity of aldosterone, a steroid hormone associated with water retention. This fluid retention can cause certain problems to worsen such as kidney, heart, or liver diseases or conditions. Taking this medication causes higher amounts of water and sodium to be eliminated, thereby reducing water retention.

Spironolactone also prevents your body from excreting or getting rid of potassium. Notably, potassium helps reduce water retention through promoting urination and excretion of sodium during urination.

How Long Does It Take for Spironolactone to Work?

The time it takes for this drug to work depends on what it is being used for and other factors, such as the presence of other medical conditions and dosage being taken. A 2012 study found that it generally takes a few weeks for spironolactone to become effective when it is used for treating acne.

Do Not Use Spironolactone If:

There are several situations where this medication may not be the right choice for you. According to the FDA, the following should not use spironolactone:

  • Patients with hyperkalemia (high potassium)
  • Patients with Addison’s disease (hypocortisolism or adrenal insufficiency)
  • Patients who are using eplerenone (Inspra)

Please note that this list may not be complete, and there may be other situations where use of this drug is not advisable.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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