Should I Take Spironolactone for Weight Loss?

Obesity and being overweight affects close to 40 percent of United States adults, according to the National Center for Health Statistics. This epidemic has caused many people to turn to fad diets, fat-burning supplements, and prescription drugs for quick weight loss.

One drug prescribed for weight loss is spironolactone. However, no scientific study has evaluated this medication specifically for weight loss. Though often prescribed, it remains unclear if spironolactone is effective for losing weight.

What Is Spironolactone?

Spironolactone (Aldactone®) is a prescribed diuretic, which means that it causes fluid elimination from the body, according to the US National Library of Medicine.

Spironolactone was approved by the U.S. Food and Drug Administration (FDA) to treat a variety of health issues. It is described as a potassium-sparing diuretic, or water pill. As your body flushes water, spironolactone is supposed to prevent your body from absorbing too much sodium and nevertheless keep your potassium levels from getting too low.

The primary function of spironolactone is treating fluid retention in the body, which often leads to weight loss. However the weight loss that occurs consists of only water weight. Diuretics effectively flush out water from the body, not fat.

Spironolactone also blocks the body's androgen receptor and some of the production of androgens. Androgens are a group of hormones responsible for male traits and reproductive activity. Androgens are made in the testes, ovaries, and adrenal glands. Testosterone is the main androgen in men and converts into the estrogen hormone in women. 

Prescribed Uses 

Spironolactone is prescribed to treat several health conditions, including the following:

• High blood pressure
• Fluid buildup from liver disease
• Low potassium (it raises levels, giving its name “potassium-sparing”)
• Symptoms related to excess androgen production in females

Women who produce too much testosterone are often prescribed spironolactone to decrease the symptoms caused by an overproduction of this hormone. The following conditions are related to excess androgen production in females:

• Polycystic ovary syndrome (PCOS)
• Excessive body or facial hair growth
• Acne
• Female-pattern hair loss

Does It Work for Weight Loss?  

Spironolactone will cause the elimination of water from the body, causing weight loss, but it does not cause fat loss directly. Losing body water is not the same as losing body fat through healthy nutrition and exercise. You may become less bloated using a diuretic, but the weight will return once body fluid levels return to normal.

In some cases, taking spironolactone might result in the loss of body fat. For instance, a woman who already has high testosterone levels that contribute to insulin resistance (making it difficult to lose body fat) may find that lowering these levels with spironolactone helps with fat loss.

On the other hand, testosterone often raises metabolism and makes building muscle easier. This makes lowering the levels with medication a double-edged sword.

Although spironolactone may relieve symptoms caused by fluid retention and could be helpful for specific health conditions, there is no evidence that it promotes healthy long-term weight loss.

Should I Take It?

No one should ever take a water pill to lose weight, physicians warn.

However, spironolactone can be used effectively for specific health conditions. For instance, a woman with PCOS (causing high testosterone levels) who experiences hair loss or excess body hair may be prescribed spironolactone to relieve these symptoms.

Side Effects and Health Concerns

Taking any prescribed medication, including spironolactone, comes with side effects. Spironolactone can cause changes in blood levels of potassium. If changes are severe enough, this can result in death.

Spironolactone can interact with other drugs and may be harmful if taken during pregnancy. It can cause breast tenderness, and a stopping of periods for women, among many other symptoms.

Some of the most common side effects of taking spironolactone include:

• Stomach upset, vomiting, and diarrhea
• Dry mouth
• Headache
• Dizziness
• Drowsiness
• Irregular menstrual periods
• Post-menopausal vaginal bleeding
• Enlarged breast tissue in men (gynecomastia)
• Breast tenderness in women

Other more severe side effects include:

• Muscle pain or weakness
• Decreased urination 
• Flu-like symptoms
• Arrhythmia
• Confusion
• Numbness or tingling
• Difficulty breathing or swallowing
• Unusual bleeding or bruising
• Serious skin reactions

A Word From Verywell

Spironolactone is a prescribed diuretic (water pill) that eliminates water from the body to help treat conditions like high blood pressure. It acts differently than other potassium-sparing water pills and it does not allow your body to absorb much sodium.

The medication blocks the body's androgen receptor and is said to reduce symptoms caused by an overproduction of androgen hormone (testosterone). This may be helpful for women with high testosterone and struggling with PCOS.

Spironolactone is approved by the FDA to treat a variety of health conditions.

Scientific studies have not been conducted using spironolactone for weight loss. The drug may be helpful to reduce water weight caused by fluid retention but is not a solution for losing fat weight. Please consult your health care professional prior to taking any medications.