Does Spironolactone Cause Weight Gain?

Article Summary

Spironolactone is a popular off-label treatment for female pattern hair loss, but many users worry about gaining weight while taking it. This article breaks down how the medication works, what the research actually shows about weight changes, typical dosing for hair growth, and simple strategies to manage side effects so you can focus on healthier, fuller hair.

Full Article

Spironolactone is a potassium-sparing diuretic with anti-androgen properties that has become increasingly popular for treating hair loss, particularly female pattern hair loss. By blocking androgen receptors, spironolactone can slow hair shedding and promote regrowth in hormonally driven alopecia. 

Despite its benefits, many patients worry about potential side effects, especially whether spironolactone leads to weight gain. Anecdotally, several patients have reported weight gain when they begin taking spironolactone. In this article, we examine that concern by reviewing typical dosing for hair loss, summarizing clinical evidence on weight changes, explaining possible biological mechanisms, and outlining practical strategies to minimize unwanted weight or fluid-related effects during treatment.

What is Spironolactone?

Spironolactone is a prescription medication classified as a potassium-sparing diuretic. In other words, it is a pill that helps the body get rid of excess fluid like water and salt by increasing urination, but it prevents excessive loss of the vital mineral potassium.

It mediates this function by acting as an aldosterone antagonist. Spironolactone blocks the binding of the hormone aldosterone to its receptors, an action that regulates the body’s sodium and potassium levels.

This is why spironolactone is commonly prescribed for hypertension (high blood pressure), heart failure, and edema (swelling). By blocking aldosterone, spironolactone reduces water and salt retention and helps lower blood pressure, strain on the heart, and swelling.^[1]Carone, L., Oxberry, S.G., Twycross, R., Charlesworth, S., Mihalyo, M., Wilcock, A. (2017). Spironolactone. Journal of Pain and Symptom Management. 53(2). 288–292. Available at: … Continue reading

How Does Spironolactone Work For Hair Loss? 

Aside from blocking aldosterone receptors, spironolactone is also capable of binding to androgen receptors. These receptors typically bind to male androgen hormones like testosterone and dihydrotestosterone (DHT).^[2]Vargas-Mora, P., Morgado-Carrasco, D. (2020). Spironolactone in Dermatology: Uses in Acne, Hidradenitis Suppurativa, Female Pattern Hair Loss, and Hirsutism. Actas Dermo-Sifiliográficas (English … Continue reading

Levels of DHT above average are a common symptom in those with androgenic alopecia. In the body, the binding of DHT to androgen receptors stimulates a range of effects, including hair follicle miniaturization. That is, hairs become thinner, shorter, and weaker. This is because DHT reduces the length of the growth phase (the anagen phase) of hair follicles, while also increasing the length of the non-growing phase (the telogen phase).^[3]Ustuner, E. T. (2013). Cause of Androgenic Alopecia: Crux of the Matter. Plast Reconstr Surg Glob Open. 1(7). e64. Available at: https://doi.org/10.1097/GOX.0000000000000005,^[4]Sekhavat, H., Bar Yehuda, S., Asotra, S. (2025). Using the Mechanisms of Action Involved in the Pathogenesis of Androgenetic Alopecia to Treat Hair Loss. Int J Mol Sci. 26(21). 10712. Available at: … Continue reading

Thus, by binding androgen receptors, spironolactone can prevent the binding of DHT and, in this way, effectively “blocks” DHT to prevent hair loss.^[5]Vargas-Mora, P., Morgado-Carrasco, D. (2020). Spironolactone in Dermatology: Uses in Acne, Hidradenitis Suppurativa, Female Pattern Hair Loss, and Hirsutism. Actas Dermo-Sifiliográficas (English … Continue reading

Side effects

Because spironolactone blocks male hormones, it can lead to unwanted feminization in men, such as gynecomastia (enlarged breasts), reduced facial or body hair, and redistribution of body fat. It may also lead to a loss of libido and other sexual dysfunctions.^[6]Carone, L., Oxberry, S.G., Twycross, R., Charlesworth, S., Mihalyo, M., Wilcock, A. (2017). Spironolactone. Journal of Pain and Symptom Management. 53(2). 288–292. Available at: … Continue reading,^[7]Haynes, B.A., Mookadam, F. (2009). Male Gynecomastia. Mayo Clinic Proceedings. 84(8). 672. Available at: https://doi.org/10.4065/84.8.672

For this reason, it is usually prescribed to women but not to men for the purpose of treating non-life-threatening conditions, such as androgenic alopecia. 

Women prescribed spironolactone may experience some other side effects. For example, 15-30% of women report irregular menstruation, while fewer than 5% report breast tenderness, reduced libido, nausea, headache, and fatigue.^[8]Vargas-Mora, P., Morgado-Carrasco, D. (2020). Spironolactone in Dermatology: Uses in Acne, Hidradenitis Suppurativa, Female Pattern Hair Loss, and Hirsutism. Actas Dermo-Sifiliográficas (English … Continue reading

The Science: Hair Growth Benefits 

Oral spironolactone as a hair loss treatment has been studied across concentrations from 25 mg to 200 mg per day. Collectively, these trials demonstrate that spironolactone can provide meaningful improvements in hair growth in those with androgenic alopecia; however, not all trials have the scientific robustness to make clear conclusions on its efficacy.

Low doses (25-50 mg/day)

A pilot study of 100 women taking 25 mg spironolactone with 0.25 mg minoxidil for 12 months nearly halved hair shedding and substantially improved hair loss severity. However, the absence of a placebo control group limits interpretation, meaning the true effectiveness of low-dose spironolactone within this combination remains uncertain.^[9]Sinclair, R.D. (2018). Female pattern hair loss: a pilot study investigating combination therapy with low-dose oral minoxidil and spironolactone. International Journal of Dermatology. 57(1). … Continue reading 

Medium doses (75-100 mg/day)

A 2025 randomized, placebo-controlled pilot study over 24 weeks evaluated 100 mg daily spironolactone plus 3% topical minoxidil versus placebo plus minoxidil in women with androgenic alopecia. Both groups experienced significant increases in hair density and diameter from baseline. The spironolactone group showed greater increases in terminal hairs and hair diameter than placebo, though this difference was not statistically significant.^[10]Werachattawatchai, P., Khunkhet, S., Harnchoowong, S., Lertphanichkul, C. (2025). Efficacy and safety of oral spironolactone for female pattern hair loss in premenopausal women: a randomized, … Continue reading

Earlier research from 1991 found that women treated with 75–100 mg spironolactone did not have a significant change in hair density after 12 months, while untreated women experienced decreases, suggesting spironolactone may prevent further loss rather than promote regrowth.^[12]Rushton, D., Futterweit, W., Kingsley, D., Kingsley, P., Norris, M.J. (1990). Quantitative assessment of spironolactone treatment in women with diffuse androgen-dependent alopecia. Journal of the … Continue reading

Combination therapies appear promising. A larger study comparing 5% minoxidil alone, minoxidil with 100 mg spironolactone, and minoxidil with microneedling found all groups had increased hair density at 24 weeks. The minoxidil plus spironolactone group had greater gains than minoxidil alone, though less than the microneedling group, indicating that adding spironolactone may enhance treatment effects.^[13]Liang, X., Chang, Y., Wu, H., et al. (2022). Efficacy and Safety of 5% Minoxidil Alone, Minoxidil Plus Oral Spironolactone, and Minoxidil Plus Microneedling on Female Pattern Hair Loss: A … Continue reading

High doses (150-200 mg/day)

Early studies suggested high doses of spironolactone might benefit people with androgenic alopecia, but the supporting evidence is limited and inconsistent. 

A very small trial reported large improvements in hair growth and reductions in hair loss after six months of 200 mg daily treatment; however, this study involved only four patients and lacked a control group, severely limiting its reliability.^[15]Adamopoulos, D.A., Karamertzanis, M., Nicopoulou, S., Gregoriou, A. (1997). Beneficial effect of spironolactone on androgenic alopecia. Clinical Endocrinology. 47(6). 759–760. Available at: … Continue reading 

Larger research has failed to confirm such strong effects. In a study of 80 women comparing spironolactone with another anti-androgen, no significant difference was found between treatments. Overall, only 44% of participants experienced regrowth, while the same proportion saw no clear change and 12% continued to lose hair.^[16]Sinclair, R., Wewerinke, M., Jolley, D. (2005). Treatment of female pattern hair loss with oral antiandrogens. British Journal of Dermatology. 152(3). 466–473. Available at: … Continue reading  

Indeed, case evidence suggests that spironolactone alone may not provide long-term benefits. A 53-year old woman with androgenic alopecia was treated with 200 mg spironolactone daily. Hair regrowth was evident after 12 months, but regrowth was not sustained after 24 months. Adding topical minoxidil alongside oral spironolactone to a treatment routine appeared to restore and maintain regrowth, indicating that combination therapy may be more effective than spironolactone on its own.^[17]Hoedemaker, C., Van Egmond, S., Sinclair, R. (2007). Treatment of female pattern hair loss with a combination of spironolactone and minoxidil. Australasian Journal of Dermatology. 48(1). 43–45. … Continue reading 

Is Spironolactone Effective for Hair Loss?

Evidence does not support spironolactone alone as an effective hair-loss treatment, especially at higher doses. Medium doses around 100 mg/day may slow further loss, but regrowth is poorly supported. Across all doses, spironolactone works best in combination therapies, particularly with minoxidil, where sustained regrowth is more consistently observed.

Does Spironolactone Have Any Mechanism That Could Cause Weight Gain? 

There is no plausible biological mechanism by which spironolactone would cause true weight gain (i.e., fat accumulation). Typically, drugs that cause weight gain will cause one or more specific effects that can lead to fat-gain.^[18]Verhaegen, A.A., Van Gaal, L.F. (2000). Drugs That Affect Body Weight, Body Fat Distribution, and Metabolism. Endotext. MDText.com, Inc. Available at: http://www.ncbi.nlm.nih.gov/books/NBK537590/ These include:

 

• Increased appetite
• Changed insulin resistance
• Slowdown of metabolism
• Increased cortisol

However, spironolactone has no known interactions that would lead to these effects. In fact, because spironolactone blocks aldosterone, it reduces sodium and water retention in the blood and can cause mild weight loss due to its diuretic effect. 

Spironolactone and Weight Gain: What Do We See from Clinical Evidence?

Many clinical studies assessing the effectiveness of spironolactone for hair loss or other medical conditions also report side effects. As doses increase, more side effects are likely to occur, but is weight gain one of them? 

Low doses (25-50 mg/day)

In the pilot study by Sinclair in 2018, side effects were reported in eight women, but they were not related to weight gain.^[19]Sinclair, R.D. (2018). Female pattern hair loss: a pilot study investigating combination therapy with low-dose oral minoxidil and spironolactone. International Journal of Dermatology. 57(1). … Continue reading

Medium doses (75-100 mg/day)

The trial by Werachattawatchai and colleagues in 2025 reported menstrual irregularities in 37.5% of women but no mention of weight gain.^[20]Werachattawatchai, P., Khunkhet, S., Harnchoowong, S., Lertphanichkul, C. (2025). Efficacy and safety of oral spironolactone for female pattern hair loss in premenopausal women: a randomized, … Continue reading Similarly, in the study by Rushton and colleagues in 1991, some women reported changes to their menstrual cycles, but there was again no mention of weight gain.^[21]Rushton, D., Futterweit, W., Kingsley, D., Kingsley, P., Norris, M.J. (1990). Quantitative assessment of spironolactone treatment in women with diffuse androgen-dependent alopecia. Journal of the … Continue reading 

The trial by Liang and colleagues in 2022 also had no reports of weight gain, but the spironolactone group had the most adverse effects reported. Menstrual disorder, hyperkalemia, and edema of the limbs occurred only within groups receiving spironolactone treatment. While it may appear paradoxical as spironolactone is designed to treat edema, spironolactone can also cause edema because it promotes shifts in fluids from the bloodstream to the tissues. ^[22]Liang, X., Chang, Y., Wu, H., et al. (2022). Efficacy and Safety of 5% Minoxidil Alone, Minoxidil Plus Oral Spironolactone, and Minoxidil Plus Microneedling on Female Pattern Hair Loss: A … Continue reading 

When used to treat hormonal disorders, a prospective clinical trial with women with polycystic ovary syndrome showed that intake of 100 mg spironolactone per day was not associated with weight gain.^[24]Zulian, E., Sartorato, P., Benedini, S., et al. (2005). Spironolactone in the treatment of polycystic ovary syndrome: Effects on clinical features, insulin sensitivity and lipid profile. Journal of … Continue reading

High doses (150-200 mg/day)

Adamopoulos and colleagues reported that participants experienced no adverse side effects from taking 200 mg spironolactone per day.^[25]Adamopoulos, D.A., Karamertzanis, M., Nicopoulou, S., Gregoriou, A. (1997). Beneficial effect of spironolactone on androgenic alopecia. Clinical Endocrinology. 47(6). 759–760. Available at: … Continue reading In the study by Sinclair in 2005 and case study by Hoedemaker and colleagues, adverse reactions, including weight gain, were not noted in the report, which suggests side effects were not measured.^[26]Sinclair, R., Wewerinke, M., Jolley, D. (2005). Treatment of female pattern hair loss with oral antiandrogens. British Journal of Dermatology. 152(3). 466–473. Available at: … Continue reading,^[27]Hoedemaker, C., Van Egmond, S., Sinclair, R. (2007). Treatment of female pattern hair loss with a combination of spironolactone and minoxidil. Australasian Journal of Dermatology. 48(1). 43–45. … Continue reading

In applications outside of hair loss, spironolactone has shown to actually cause weight loss. Administration of up to 200 mg spironolactone to patients with mineralocorticoid-induced hypertension resulted in a reversal of mineralocorticoid-induced abnormalities, including increased body weight.^[28]Nicholls, M.G., Ramsay, L.E., Boddy, K., Fraser, R., Morton, J.J., Robertson, J.I.S. (1979). Mineralocorticoid-induced blood pressure, electrolyte, and hormone changes, and reversal with … Continue reading

Why Some People Think Spironolactone Causes Weight Gain

Even though spironolactone has no known mechanism that could cause weight gain, and has actually been shown to induce weight loss, some individuals taking spironolactone have reported weight gain anecdotally. Why could this be?

1. Water Retention

Spironolactone helps your body get rid of salt and water. It works by making the kidneys remove sodium and water from the bloodstream, which lowers the amount of fluid circulating in the vessels. That helps when edema is caused by too much circulating volume, like in heart failure or certain hormone disorders.

However, spironolactone can also relax veins and lower blood pressure. Edema can be caused by these exact symptoms. Thus, spironolactone can sometimes make fluid move into your tissues instead of staying in your bloodstream, causing swelling. This is why some studies report edema as a side effect. 

Those in spironolactone may experience this water retention and swelling, causing them to feel that they have gained weight as a result of taking this medication. 

1. Multiple Medications

It is likely that the individual is taking multiple medications. Spironolactone is best used in combination with other medications, and is safe to use with anti-depressants or birth control, both of which have clinically shown to cause weight gain.^[29]Gafoor, R., Booth, H.P., Gulliford, M.C. (2018). Antidepressant utilisation and incidence of weight gain during 10 years’ follow-up: population based cohort study. BMJ. k1951. Available at: … Continue reading,^[30]Lopez, L.M., Ramesh, S., Chen, M., et al. (2016). Progestin-only contraceptives: effects on weight. Cochrane Database of Systematic Reviews. 2016(8). CD008815. Available at: … Continue reading. Research summarising population characteristics of those prescribed spironolactone found that 22% had been using hormonal contraceptives, suggesting an alternative reason than spironolactone for reported weight gain.^[31]Burns, L.J., Souza, B.D., Flynn, E., Hagigeorges, D., Senna, M.M. (2020). Spironolactone for treatment of female pattern hair loss. Journal of the American Academy of Dermatology. 83(1). 276–278. … Continue reading

1. Menopause

Weight gain is also one of the most common side effects of perimenopause, menopause, and postmenopause, affecting over 40% of women.^[32]Knight, M.G., Anekwe, C., Washington, K., Akam, E.Y., Wang, E., Stanford, F.C. (2021). Weight Regulation in Menopause. Menopause. 28(8). 960–965. Available at: … Continue reading,^[33]Davis, S.R., Castelo-Branco, C., Chedraui, P., et al. (2012). Understanding weight gain at menopause. Climacteric. 15(5). 419–429. Available at: https://doi.org/10.3109/13697137.2012.707385 Population characteristics of those prescribed spironolactone found that 51% were postmenopausal.^[34]Burns, L.J., Souza, B.D., Flynn, E., Hagigeorges, D., Senna, M.M. (2020). Spironolactone for treatment of female pattern hair loss. Journal of the American Academy of Dermatology. 83(1). 276–278. … Continue reading Weight gain may therefore be related to life stage rather than spironolactone itself.

1. Other Side Effects

Many medications including spironolactone itself may cause symptoms such as fatigue. Those experiencing fatigue would be less inclined to stick to their active routines. Inactivity or changes to diet as a result could lead to weight gain. 

1. Stress

We must also consider that external factors like stress can cause hormonal changes that influence weight. It is reasonable to assume that those prescribed spironolactone may be experiencing hypertension, heart failure, edema, or hair loss. Ongoing conditions like these could contribute to stress and hormonal changes that ultimately lead to weight gain.^[35]Kyrou, I., Tsigos, C. (2009). Stress hormones: physiological stress and regulation of metabolism. Current Opinion in Pharmacology. 9(6). 787–793. Available at: … Continue reading

Managing Weight Fluctuations If They Occur 

Because spironolactone has a diuretic effect, you may notice some temporary weight loss due to fluid reduction. This is not fat loss, but if you wish to maintain your weight, it’s important to monitor your body closely and make gradual lifestyle changes. The same can be advised if you are also experiencing weight gain for any reason.

To manage weight fluctuations if they occur, consider the following:

• Record keeping: Keep a consistent record of your weight to track change and distinguish between fluid-related changes and true weight changes

• Diet: Maintain a balanced diet rich in whole grains, lean proteins, healthy fats, fruits, and vegetables to stabilize weight.

• Hydration: Fluid shifts from diuretics can sometimes trigger dehydration, which may influence appetite and energy levels.

• Physical activity: Support muscle maintenance and overall metabolism by engaging in regular physical activity 

• Take time: Weight changes from spironolactone are often temporary as your body gets used to the medication

If you feel your medication is causing your weight to change substantially, speak with your clinician, as it may indicate problems with your dosage, interactions with other medications, or additional health conditions.

Should I Take Spironolactone If I’m Concerned About Weight Gain?  

There are some side effects of spironolactone, but weight gain is not one of them. Clinical evidence shows that daily usage of spironolactone at any dose is not known to cause weight gain.

If you’ve been prescribed spironolactone, take it with peace of mind that it will not cause permanent changes to your weight.

Final Verdict 

Spironolactone isn’t a “fat-gain” drug, even though it can sometimes get that reputation online. Any early weight changes are usually from temporary fluid shifts, and many people actually notice weight loss over time due to the diuretic activity of this treatment.

Benefits to hair loss tend to appear at moderate doses like 50-100 mg per day and are most substantial when combined with common hair loss treatments like minoxidil. True weight gain has not been reported clinically, and anecdotal evidence from users is likely the result of other medications, age, activity level, or hormonal shifts. That being said, pairing treatment with sensible eating, hydration, and regular activity can help keep any weight changes in check, so the only thing you see growing is your hair.