What Are the Cons of Taking Spironolactone?

October 7, 2025 •

4 min read

In 2023, spironolactone was the 52nd most commonly prescribed medication in the United States, with over 12 million prescriptions [1.4.4]. Despite its benefits for conditions like heart failure and acne, it is essential to understand what are the cons of taking spironolactone.

Quick Summary

The primary disadvantages of taking spironolactone include the risk of developing high potassium levels (hyperkalemia), hormonal side effects like breast tenderness, and menstrual irregularities. Other cons are potential dehydration, drug interactions, and dizziness [1.2.1, 1.4.1].

Key Points

Hyperkalemia Risk: A primary con is the risk of dangerously high blood potassium levels, which requires monitoring through blood tests [1.2.4].
Hormonal Side Effects: The drug commonly causes breast enlargement (gynecomastia) in men and menstrual irregularities in women [1.2.1, 1.3.2].
Drug Interactions: It can interact with common drugs like ACE inhibitors, ARBs, and NSAIDs, increasing the risk of high potassium [1.2.1, 1.3.6].
Dehydration and Dizziness: As a diuretic that lowers blood pressure, it can cause increased urination, dehydration, dizziness, and fatigue [1.2.2, 1.2.8].
Contraindications: Spironolactone should not be used by individuals with severe kidney problems, Addison's disease, or existing high potassium levels [1.4.1].
Not Safe for Pregnancy: The medication is contraindicated in pregnancy due to the risk of causing birth defects [1.2.3, 1.2.9].
Dose-Dependent Effects: Many side effects, such as menstrual changes and gynecomastia, are more likely to occur at higher doses [1.2.1].

Spironolactone, sold under brand names like Aldactone, is a potassium-sparing diuretic ("water pill") used to treat high blood pressure, heart failure, and fluid buildup (edema) [1.2.2, 1.2.5]. It's also frequently prescribed off-label for hormonal acne and hair growth in women [1.2.3, 1.4.4]. While effective, the medication carries several notable disadvantages and potential side effects that patients and healthcare providers must carefully consider.

The Primary Con: Hyperkalemia (High Potassium)

One of the most significant cons of spironolactone is its potential to cause hyperkalemia, or dangerously high levels of potassium in the blood [1.2.4, 1.4.1]. Because it is a potassium-sparing diuretic, it helps the body get rid of excess fluid without losing potassium [1.2.5]. This action can lead to an accumulation of potassium, which can be serious and, in rare cases, fatal [1.2.4, 1.4.4].

Symptoms of hyperkalemia can be mild and easily missed but may include:

Muscle weakness or fatigue [1.2.1]
Nausea and vomiting [1.2.1]
Numbness or tingling sensations [1.2.1]
Irregular heartbeat or palpitations [1.2.1, 1.3.3]
Shortness of breath [1.2.1]

The risk of developing hyperkalemia is higher in certain individuals, including the elderly, those with kidney disease, Addison's disease, or diabetes [1.4.4, 1.3.9]. Regular blood tests to monitor potassium levels are crucial, especially when starting the medication or adjusting the dose [1.2.2].

Hormonal and Gender-Specific Side Effects

Spironolactone works by blocking the effects of aldosterone and, to a lesser extent, testosterone [1.4.4]. This anti-androgenic effect is beneficial for treating hormonal acne but also leads to a range of hormonal side effects.

Cons for Men

For male patients, the hormonal side effects are a significant drawback and often lead to discontinuation. These are some of the most common cons reported in clinical trials [1.2.1, 1.3.2].

Gynecomastia: Development of breast tissue in men is one of the most common side effects [1.2.1]. It can include breast pain, tenderness, and swelling, and its likelihood increases with higher doses [1.3.6]. This effect is usually reversible after stopping the medication [1.3.6].
Decreased Libido: A reduced sex drive is another common complaint [1.3.1].
Erectile Dysfunction: Difficulty achieving or maintaining an erection can occur [1.3.2, 1.3.1].

Cons for Women

While often prescribed to women for dermatological issues, spironolactone can cause disruptive side effects.

Menstrual Irregularities: This is a very common side effect and can include irregular periods, spotting between periods (breakthrough bleeding), heavier bleeding, or missed periods (amenorrhea) [1.2.1, 1.4.4]. These effects are more common at higher doses [1.4.4].
Breast Tenderness: Breast pain and tenderness are frequently reported by women taking the drug [1.2.2, 1.6.5].
Pregnancy Risks: Spironolactone is not safe for use during pregnancy as it can cross the placenta and potentially cause birth defects [1.2.3, 1.2.9]. Reliable birth control is essential for women of childbearing age taking this medication [1.6.1].

Common and Other Serious Cons

Beyond hormonal issues and hyperkalemia, spironolactone has other disadvantages.

Dizziness and Drowsiness: As a blood pressure-lowering medication, it can cause dizziness, lightheadedness, and drowsiness, especially when first starting or after a dose increase [1.2.1, 1.3.3]. This can affect your ability to drive or operate machinery [1.2.8].
Dehydration and Electrolyte Imbalance: Its function as a diuretic means it increases urination, which can lead to dehydration if fluid intake is not adequate [1.2.2, 1.2.8]. It can also cause other electrolyte imbalances, such as low sodium (hyponatremia), low magnesium, and low calcium [1.2.4, 1.3.1].
Kidney Problems: In some cases, the diuretic effect and potential for low blood pressure can lead to worsening kidney function [1.2.4, 1.3.9]. It is contraindicated in patients with significant renal impairment [1.4.1].
Drug and Food Interactions: Spironolactone can interact negatively with other medications and even some foods. Combining it with ACE inhibitors, ARBs, or NSAIDs (like ibuprofen) significantly increases the risk of hyperkalemia [1.2.1, 1.3.6]. Patients are also advised to avoid potassium supplements and salt substitutes containing potassium [1.5.2]. Limiting foods very high in potassium, such as bananas, avocados, and coconut water, may also be recommended [1.2.3, 1.5.2].

Comparison of Cons: Spironolactone vs. Topical Retinoids for Acne


Feature	Spironolactone	Topical Retinoids (e.g., Tretinoin)
Mechanism	Systemic (oral), blocks androgen hormones [1.6.1]	Topical, increases skin cell turnover
Primary Cons	Systemic side effects: Hyperkalemia, menstrual irregularities, breast tenderness, dizziness [1.4.1, 1.6.5]	Local side effects: Skin irritation, dryness, peeling, redness, sun sensitivity
Contraindications	Kidney disease, hyperkalemia, Addison's disease, pregnancy [1.4.1, 1.2.3]	Pregnancy, certain skin conditions (e.g., eczema)
Monitoring	Requires periodic blood tests for potassium and kidney function [1.2.2]	Generally does not require lab monitoring
Time to Effect	Can take up to 3-4 months to see improvement [1.2.3, 1.2.5]	Can take 8-12 weeks to see improvement

Conclusion

While spironolactone is a valuable medication for many conditions, the cons are significant and require careful management. The risk of hyperkalemia necessitates regular monitoring, and the hormonal side effects, such as gynecomastia in men and menstrual cycle disruptions in women, can impact quality of life. Furthermore, potential interactions with other common drugs and the absolute contraindication in pregnancy make it a medication that must be used under strict medical supervision. Anyone considering or currently taking spironolactone should have an open dialogue with their healthcare provider about these potential downsides to ensure the benefits outweigh the risks.

For more detailed information, consult the U.S. National Library of Medicine's page on Spironolactone. [1.5.4]

Frequently Asked Questions

Early signs of high potassium (hyperkalemia) can be subtle or absent, but may include muscle weakness, fatigue, nausea, numbness or tingling, and a slow or irregular heartbeat [1.2.1, 1.3.3].

Drinking alcohol while taking spironolactone can increase side effects like dizziness and drowsiness [1.2.8, 1.5.2]. If you are taking it for liver problems, alcohol should be avoided entirely [1.5.2].

Weight gain is not a commonly reported side effect; in fact, due to its diuretic effect, some temporary weight loss from water reduction may occur [1.2.2, 1.6.9]. Significant weight changes should be discussed with a doctor.

Spironolactone can cause breast tenderness and enlargement due to its hormonal effects, specifically its mild estrogen-like activity and its function as an anti-androgen [1.4.4, 1.2.2]. This can occur in both men and women [1.3.1].

You should avoid salt substitutes that contain potassium [1.5.2]. It is also often recommended to limit excessive intake of foods very high in potassium, like bananas, avocados, coconut water, and spinach, to reduce the risk of hyperkalemia [1.2.3, 1.5.2].

Some side effects like dizziness and increased urination may be temporary and last a few days to weeks [1.2.1]. Hormonal side effects like gynecomastia are often dose-dependent and typically resolve after the medication is stopped or the dose is lowered [1.3.6].

Yes, increased urination is a common side effect due to its diuretic action [1.2.2]. While this is the intended effect for treating fluid retention, it can be an inconvenient con, potentially leading to dehydration and disrupting sleep if taken at night [1.2.5, 1.2.8].