Short answer: Yes. Spironolactone is an anti-androgen that reduces unwanted hair, and in a Cochrane review it lowered hair scores by about 7.7 points more than placebo.[1] The Endocrine Society names 100 to 200 mg a day as the therapeutic dose for hirsutism, and results take about 6 months to show and about 9 months to peak.[2] Because it can affect the development of a male fetus, you need reliable contraception while taking it, and hair usually grows back within about a year if you stop.[3], [4]
Spironolactone is licensed for heart failure, high blood pressure and fluid retention,[3] but it also blocks the effects of androgens (hormones such as testosterone) on hair follicles.[5] That second effect is why doctors prescribe it for hirsutism. This guide covers what the evidence shows, how long it takes, the doses guidelines mention, the side effects to know about, and how it fits with the pill. For an overview of all prescription options, see our guide to hirsutism medication.
Does spironolactone work for hirsutism?
Evidence: Strong Yes. Spironolactone reduces hirsutism compared with placebo, and both major guidelines include it as a treatment option. A Cochrane review by van Zuuren and colleagues (157 trials and 10,550 women in total, searched to June 2014) found spironolactone lowered Ferriman-Gallwey hair scores by an average of 7.69 points more than placebo, and it appeared about as effective as flutamide and finasteride.[1] The review authors noted a limitation: For spironolactone, the only data available came from doctors’ assessments, not from the women themselves.[6]
A 2018 network meta-analysis that informed the Endocrine Society guideline pooled 43 randomized trials. It found anti-androgens as a group worked better than placebo, and spironolactone, finasteride and flutamide were each better than placebo but similar to one another. The certainty of the evidence was rated moderate for comparisons with placebo and low for head-to-head comparisons.[7]
Spironolactone reduces new hair growth rather than removing hair you already have.
How does spironolactone reduce unwanted hair?
Spironolactone mainly works by blocking androgen receptors, so testosterone and its stronger form, dihydrotestosterone (DHT), have less effect on hair follicles.[5] Androgens are what turn fine, light hair into coarse, dark hair in hormone-sensitive areas such as the chin, upper lip, chest and abdomen. Spironolactone was developed as an aldosterone antagonist, which means it also makes the kidneys hold on to potassium and pass more water. That is the reason for some of its side effects.[3]
The most common cause of hirsutism is PMOS (formerly PCOS), renamed polyendocrine metabolic ovarian syndrome in 2026,[8] and the 2023 International PCOS Guideline includes anti-androgens for hirsutism in this condition.[9] Read more about PMOS facial hair.
How long does spironolactone take to work for hirsutism?
Expect to wait at least 6 months. The Endocrine Society’s 2018 guideline says it takes about 6 months to detect the effects of hormonal therapy and about 9 months for the effects to become maximal, and it suggests a trial of at least 6 months before changing the dose, switching drugs or adding another medicine.[2]
The reason is the hair growth cycle. Hairs grow in cycles that are not in sync with each other, and the growth (anagen) phase of facial hair lasts about 4 months.[2] Spironolactone changes the hair that grows next. Hairs already in their growth phase keep growing, so many months pass before most follicles have cycled through. The 2023 International PCOS Guideline uses the same 6-month benchmark before adding an anti-androgen to the pill.[9]
What dose of spironolactone is used for hirsutism?
Guidelines and references give a range rather than a single dose, and your doctor will choose one based on your health, other medicines and side effects. These are the figures in the sources we checked. They are not personal dosing advice.
| Source | What it says about dose |
|---|---|
| Endocrine Society guideline, 2018 | “100 to 200 mg spironolactone is the therapeutic dose for hirsutism”[2] |
| Endocrine Society guideline, 2008 | 100 to 200 mg a day, given in divided doses (twice daily)[4] |
| International PCOS Guideline, 2023 | 25 to 100 mg a day “appears to have lower risks of adverse effects”[9] |
| DermNet (dermatology reference) | Usually increased slowly from 25 to 200 mg daily[5] |
The Endocrine Society focuses on the dose that works best for hair, while the 2023 PCOS guideline highlights the lower range for safety. DermNet notes the dose is usually increased gradually.[5]
Is spironolactone approved for hirsutism?
No. In the US, the FDA label lists heart failure, high blood pressure, swelling (edema) and primary hyperaldosteronism, not hirsutism.[3] In the UK, the licensed uses in the summary of product characteristics are also heart, liver, kidney and aldosterone-related conditions, so using it for hirsutism is off-label (called “unlicensed” in the UK).[10] Off-label prescribing is legal and common. Both the Endocrine Society and the International PCOS Guideline include anti-androgens such as spironolactone in their hirsutism recommendations.[2], [9]
Why do you need birth control while taking spironolactone?
Spironolactone may affect the sexual development of a male fetus. The FDA label says it “may affect sex differentiation of the male during embryogenesis,” based on rat studies that showed feminization of male fetuses, and advises avoiding it in pregnancy.[3] The 2008 Endocrine Society guideline describes the danger of “fetal male pseudohermaphroditism” (incomplete development of male genitals) if it is used in pregnancy.[4]
For this reason, the 2018 Endocrine Society guideline suggests against starting an anti-androgen on its own unless you use adequate contraception. It makes an exception for women who are not sexually active, have been sterilized, or use long-acting reversible contraception such as an IUD or implant.[2] The 2023 International PCOS Guideline also recommends anti-androgens only “in combination with effective contraception.”[9] If you are trying to get pregnant, talk to your doctor about stopping spironolactone first.
Should you take spironolactone with the birth control pill?
Evidence: Moderate For most women, guidelines suggest starting with the pill and adding spironolactone later if needed. The Endocrine Society’s 2018 guideline suggests a combined oral contraceptive as the first treatment for most women with hirsutism who are not trying to conceive, and adding an anti-androgen if bothersome hair remains after 6 months on the pill alone.[2] The 2023 International PCOS Guideline gives the same advice for women with PMOS: Consider an anti-androgen if the response is not good enough after at least 6 months of the pill and/or cosmetic treatment.[9]
The combination works a bit better than the pill alone. In the 2018 network meta-analysis, the pill plus an anti-androgen was superior to the pill alone,[7] and the Endocrine Society describes the added benefit as “slightly more effective.”[2] The guideline suggests starting both together only in some cases, for example severe hirsutism causing distress or a past trial of the pill that did not help enough, and not as a standard first step.[2]
One practical point: Pills containing drospirenone have a mild spironolactone-like effect on potassium. The US label for a drospirenone pill advises checking potassium during the first cycle in women who take aldosterone antagonists, which include spironolactone, every day.[11] Our guide to the best birth control pill for hirsutism compares the options.
What are the side effects of spironolactone?
The most common problem for women taking spironolactone for hair is irregular bleeding. The Cochrane review linked spironolactone to irregular bleeding,[6] the FDA label lists irregular periods or no periods, and the 2008 Endocrine Society guideline says menstrual irregularity may be dose-dependent.[3], [4] Other side effects listed by the NHS and the FDA label include:[12], [3]
- Dizziness, headache and drowsiness
- Feeling sick (nausea), tiredness and leg cramps
- Breast pain or tenderness
- Passing more urine (it is a diuretic)[4]
- High potassium (hyperkalemia), which is uncommon in healthy young women but can cause muscle weakness and an irregular heartbeat[12]
Rare but serious reactions listed by the NHS include severe allergic reactions, serious skin reactions, and liver or kidney problems.[12] Contact a doctor urgently if you notice yellowing skin, a rash with blisters, or muscle weakness with a pounding or irregular heartbeat.
Do you need potassium blood tests on spironolactone?
It depends on your health. A study of 974 healthy young women taking spironolactone for acne (published in 2015 in JAMA Dermatology) found that 13 of 1,802 potassium tests were abnormal, a rate of 0.72%, which matched the 0.76% baseline rate in similar women. The authors concluded routine potassium monitoring was unnecessary for healthy women in that group.[13] The risk is higher if you have kidney problems or take potassium supplements or certain blood pressure drugs (ACE inhibitors or ARBs).[3] Some references still recommend checking potassium and kidney function before and after starting,[5] so follow your doctor’s plan. The NHS also advises asking your doctor before eating lots of high-potassium foods or using salt substitutes.[12]
Who shouldn’t take spironolactone?
Spironolactone is not suitable for everyone. According to the FDA label, the UK product information and the NHS, you should not take it, or should only take it after specialist advice, if you:[3], [10], [12]
- Have high potassium levels, now or in the past
- Have Addison’s disease (adrenal insufficiency)
- Have severe kidney problems or cannot pass urine
- Take eplerenone or another potassium-sparing diuretic
- Are pregnant or trying to get pregnant
- Are allergic to spironolactone
Tell your doctor about all your medicines. The FDA label warns about potassium supplements, ACE inhibitors and ARBs, lithium (spironolactone can raise lithium levels), and anti-inflammatory painkillers (NSAIDs).[3] The NHS adds digoxin.[12]
How does spironolactone compare with other anti-androgens?
The 2018 Endocrine Society guideline does not favor one anti-androgen over another, but it recommends against flutamide because of possible liver damage.[2] This table summarizes what our sources say.
| Medicine | How it works | Doses mentioned in sources | Main cautions |
|---|---|---|---|
| Spironolactone | Blocks androgen receptors[5] | 25 to 200 mg a day (see dose table above) | Off-label; irregular bleeding; potassium; needs contraception[3], [2] |
| Cyproterone acetate | Progestin that blocks androgen receptors[2] | 2 mg in some pills; higher doses (for example 50 mg on days 1 to 10) as a separate tablet[2], [14] | Not available in the US.[4] In Europe, daily doses of 10 mg or more are restricted because of meningioma risk[15] |
| Finasteride | Blocks 5-alpha reductase, the enzyme that makes DHT[5] | Not specified in the guidelines we checked | Cochrane found no convincing benefit; needs contraception[6], [2] |
| Flutamide | Anti-androgen mainly used for prostate cancer[5] | 250 to 500 mg a day in older studies[5] | Can cause hepatitis; the Endocrine Society recommends against it[2], [5] |
| Drospirenone (in some pills) | Weak anti-androgen related to spironolactone[2] | 3 mg per pill, which equals only about 9 to 10 mg of spironolactone in anti-androgen effect[2] | Possible higher blood clot risk than levonorgestrel pills[11] |
The network meta-analysis found spironolactone, finasteride and flutamide similarly effective,[7] so in practice the choice often comes down to safety and availability.
Can you take spironolactone while breastfeeding?
Sources disagree, so this is a decision to make with your doctor. LactMed, the US National Library of Medicine’s breastfeeding database, says spironolactone is poorly excreted into breast milk and “appears to be acceptable” during breastfeeding. In the one mother studied, the baby would have received about 0.2% of her dose as the metabolite canrenone, and the few infants reported had no problems.[16] The FDA label also describes only low levels of canrenone in milk.[3]
The UK product information is more cautious and says spironolactone should not be used during breastfeeding,[10] while the NHS says you may be able to take it after checking with a doctor.[12] After giving birth, remember that spironolactone still requires reliable contraception. Read more about hirsutism in pregnancy and after birth.
What happens when you stop taking spironolactone?
The hair usually comes back. The 2008 Endocrine Society guideline notes that in women treated with spironolactone alone, hirsutism scores returned to baseline within a year of stopping.[4] A 1999 study of 81 women in Turkey treated with spironolactone 100 mg plus the pill, cyproterone acetate plus the pill, or flutamide found that hirsutism had returned in all three groups one year after treatment stopped.[14]
Spironolactone controls the effect of androgens while you take it but does not change the cause, so many women stay on it or combine it with laser or electrolysis. The Endocrine Society suggests using medication alongside laser to reduce regrowth.[2] See PMOS hair removal for what works when hormones are the cause.
When should you see a doctor?
See a doctor before starting any anti-androgen. Hirsutism can be a sign of PMOS or, rarely, another hormonal condition, and spironolactone needs a prescription, contraception planning and a check of your kidney function and medicines. Get seen promptly if you notice:
- Hair growth that started suddenly or is getting worse within months
- A deepening voice, an enlarged clitoris or male-pattern hair loss (signs of virilization)
- Irregular or missing periods
- On spironolactone: Muscle weakness, an irregular heartbeat, fainting, or a positive pregnancy test
Not sure who to see? Our guide to which doctor is best for hirsutism has a tool to help you decide, and the hirsutism self-check helps you describe your symptoms.
Frequently asked questions
Can I take spironolactone without birth control?
Guidelines advise against it unless you cannot get pregnant or already use reliable contraception such as an IUD or implant. Spironolactone may affect the development of a male fetus, so the Endocrine Society suggests pairing it with adequate contraception.[2], [3]
Is 25 mg of spironolactone enough for hirsutism?
It may be for some women, but it is at the low end. The 2023 International PCOS Guideline says 25 to 100 mg a day appears to have fewer side effects, while the Endocrine Society calls 100 to 200 mg the therapeutic dose for hirsutism.[9], [2] Give any dose at least 6 months before judging it.
Will spironolactone get rid of hair I already have?
Not on its own. It reduces how much new coarse hair grows over several hair cycles, so most women still need some hair removal. Guidelines suggest combining medication with laser or electrolysis.[2]
Does spironolactone help PMOS facial hair?
Yes, it is one of the anti-androgens recommended for hirsutism in PMOS (formerly PCOS). The 2023 International PCOS Guideline suggests considering it if the pill has not helped enough after at least 6 months, together with effective contraception.[9]
Key takeaways
- Spironolactone reduces hirsutism compared with placebo and is included in both major hirsutism guidelines, but it is off-label in the US and UK.
- Doses in guidelines range from 25 to 200 mg a day, and the Endocrine Society calls 100 to 200 mg the therapeutic dose for hirsutism.
- Allow at least 6 months for results and about 9 months for the full effect, because hair grows in slow cycles.
- Use reliable contraception while taking it. Most guidelines suggest starting with the pill and adding spironolactone after 6 months if needed.
- Irregular bleeding is the most common side effect, and hair usually returns within a year of stopping.
Sources
- van Zuuren EJ, Fedorowicz Z. Interventions for hirsutism excluding laser and photoepilation therapy alone: abridged Cochrane systematic review including GRADE assessments. Br J Dermatol. 2016;175(1):45-61. PubMed 26892495
- Martin KA, Anderson RR, Chang RJ, et al. Evaluation and Treatment of Hirsutism in Premenopausal Women: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2018;103(4):1233-1257. PubMed 29522147
- US Food and Drug Administration. Aldactone (spironolactone) tablets: prescribing information (revised November 2025). Accessed October 2026. Link
- Martin KA, Chang RJ, Ehrmann DA, et al. Evaluation and Treatment of Hirsutism in Premenopausal Women: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2008;93(4):1105-1120. PubMed 18252793
- DermNet. Anti-androgen therapy. Accessed October 2026. Link
- Cochrane. Treatments for unwanted male pattern hair growth in women (plain language summary of van Zuuren EJ, Fedorowicz Z, Carter B, Pandis N. Interventions for hirsutism (excluding laser and photoepilation therapy alone). Cochrane Database Syst Rev. 2015;(4):CD010334). Accessed October 2026. Link
- Barrionuevo P, Nabhan M, Altayar O, et al. Treatment Options for Hirsutism: A Systematic Review and Network Meta-Analysis. J Clin Endocrinol Metab. 2018;103(4):1258-1264. PubMed 29522176
- Teede HJ, Bahri Khomami M, Morman R, et al. Polyendocrine metabolic ovarian syndrome, the new name for polycystic ovary syndrome: a multistep global consensus process. Lancet. 2026;407(10545):2329-2339. PubMed 42119588
- Teede HJ, Tay CT, Laven JJE, et al. Recommendations From the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome. J Clin Endocrinol Metab. 2023;108(10):2447-2469. PubMed 37580314
- Electronic Medicines Compendium (UK). Aldactone 25 mg Film-Coated Tablets: Summary of Product Characteristics (revised January 2026). Accessed October 2026. Link
- US Food and Drug Administration. Yaz (drospirenone/ethinyl estradiol) tablets: prescribing information (revised May 2023). Accessed October 2026. Link
- NHS. Spironolactone. Accessed October 2026. Link
- Plovanich M, Weng QY, Mostaghimi A. Low Usefulness of Potassium Monitoring Among Healthy Young Women Taking Spironolactone for Acne. JAMA Dermatol. 2015;151(9):941. Link
- Yücelten D, Erenus M, Gürbüz O, Durmuşoğlu F. Recurrence rate of hirsutism after 3 different antiandrogen therapies. J Am Acad Dermatol. 1999;41(1):64-68. Link
- European Medicines Agency. Restrictions in use of cyproterone due to meningioma risk (February 14, 2020). Accessed October 2026. Link
- National Library of Medicine. Drugs and Lactation Database (LactMed): Spironolactone (last revised November 15, 2023). Accessed October 2026. Link
This article is for education and is not medical advice. Talk to a doctor about diagnosis and treatment.