Spironolactone for PMOS: How It Works, Who It’s For and What to Expect

Persistent acne, facial hair you’re constantly removing, or a widening hair parting can take more time and headspace than others may realise, but we understand the toll it can take. If polyendocrine metabolic ovarian syndrome (PMOS) symptoms are affecting you, treatment is available. 

Spironolactone is one option. It’s a prescription-only medication that’s used off-label in the UK to manage certain skin and hair symptoms associated with PMOS, formerly known as PCOS. It works gradually and won’t address every aspect of PMOS, but it can improve your quality of life, confidence, and self-esteem. Here’s what spironolactone can help with, what treatment involves, and how to decide whether you’d like to discuss it with a clinician.

How Does Spironolactone Help With PMOS (PCOS)?

Spironolactone is a prescription-only medication that is given off-label to manage specific PMOS symptoms associated with your hair and skin. Off-label means it is prescribed for conditions and symptoms it isn’t licensed for, but a clinician can prescribe it if it's appropriate. Spironolactone acts as an anti-androgen by blocking androgen receptors. Androgens are male hormones, such as testosterone, that women also naturally produce but in lower amounts. In PMOS, androgen levels can be higher than usual, and your skin and hair follicles can be particularly sensitive to their effects.

How it works on androgens

By blocking androgen receptors, spironolactone reduces androgen activity in oil glands and hair follicles and can lower testosterone production.

Symptoms it may help

Spironolactone may be considered for the following PMOS symptoms:

• Hirsutism – excess hair growth on the face, chest or abdomen which may be coarser and darker than your usual hair

• Persistent acne and oily skin – breakouts of painful cyst-like spots around the chin and jawline

• Female pattern hair loss – gradual thinning over the top of your scalp or a widening parting

These symptoms may not all respond equally to spironolactone, and it is not a fertility treatment. It is often prescribed alongside other PMOS treatments to manage the hormone imbalances that may be causing your symptoms or when certain treatments are not suitable for you, such as the combined oral contraceptive pill. 

What it doesn’t do

Spironolactone is not a cure for PMOS. It will not reliably restore ovulation or treat fertility issues. It also isn’t a substitute for managing metabolic concerns or speaking to your clinician about irregular or absent periods. 

And despite what you may read online, spironolactone isn't a weight loss medication. Instead, it’s a diuretic, meaning it helps your kidneys remove salt and water from the body.* So, early weight loss may reflect water loss rather than fat loss when you start taking spironolactone. 

*NHS. (2026). Spironolactone.

Who Might Be Prescribed Spironolactone for PMOS (PCOS)?

Spironolactone may suit you if PMOS acne, excess hair growth, or scalp thinning is troublesome, affects your daily life, and other treatments haven’t helped or are unsuitable. 

For unwanted facial or body hair (hirsutism), spironolactone may be considered for adults with PMOS who cannot take, or choose not to take, the combined oral contraceptive pill. It can also be used to help manage hair loss or thinning, sometimes alongside the combined pill.*

Usually, a GP, dermatologist, or endocrinologist will prescribe spironolactone and review your medical history and symptoms to make sure it is suitable for you. Spironolactone is not recommended if you:

• Are allergic to spironolactone

• Cannot pass urine

• Have severe kidney disease

• Have Addison’s disease 

• Have high blood potassium levels (hyperkalaemia)

• Are breastfeeding

• Are taking water tablets or any potassium supplements

• Are taking eplerenone, a medication used to treat high blood pressure

• Are pregnant or trying to get pregnant**

If you think you may have PMOS but have not yet been diagnosed, speak to your GP.

*NICE. (2026). Polyendocrine metabolic ovarian syndrome (previously known as polycystic ovary syndrome): assessment and management.

**Electronic Medicines Compendium. (2025). Spironolactone 12.5 mg Film-coated Tablets.

What to Expect: Dose, Timeline and Results

Starting spironolactone can bring questions about your dose, how soon you’ll notice a difference and what improvement might look like. Your clinician will tailor treatment to your symptoms and health. Results take time, particularly for hair changes, so knowing when to expect progress can help you judge how your treatment is going.

Dose and how it’s prescribed

Spironolactone doses for PMOS vary depending on the symptom it is being used for and can be individual to you. Most doses are between 100 and 200mg per day. However, a higher dose doesn’t automatically mean it will be better. The goal is to balance improvement with tolerability. 

According to NICE, the available doses for spironolactone and PMOS are:

• Hirsutism – The starting dose of spironolactone is 100mg per day for 6 months. If it hasn't been effective by then, your clinician may increase it to 200mg daily.*

• Hair loss – If you take spironolactone with a combined oral contraceptive, start with 100mg daily for 6 months. If this is not effective, you can increase it to 200mg per day. The combined pill should contain the lowest effective dose of oestrogen for you, such as 20 to 30 micrograms (mcg) of ethinylestradiol.* 

If your clinician has prescribed spironolactone for acne, they will tell you your starting dose, how long you will need to take it, and how to take it. If you feel that your dose is too strong or too weak, speak to your clinician about adjusting your dose; you should not do this yourself as it could have dangerous side effects. 

*NICE. (2026). Polyendocrine metabolic ovarian syndrome (previously known as polycystic ovary syndrome): assessment and management.

How long does it take to work?

Unfortunately, spironolactone will not improve your symptoms overnight. It is a long-term treatment that will need time to work. It’s also possible to experience early side effects before the benefits, which can feel frustrating when you’ve already spent months trying other treatments. 

• Acne and oily skin usually start to improve within 2 to 3 months of starting treatment, with maximum clearance of spots and lesions taking up to 6 months

• Unwanted facial and body hair can start to improve around 6 months after starting treatment, but it can take up to 18 months to see noticeable benefits

• Scalp hair thinning can improve after 6 months, with continued improvement taking 12 months or more

How long spironolactone takes to work depends on several factors, including how well your body responds to the treatment, the severity of your symptoms, and which symptoms you are taking it for. 

If you are taking spironolactone for excess hair growth, it will take longer to see noticeable results than for acne or hair loss because hair follicles move through slow growth cycles. For example, even after spironolactone reduces your androgen levels, existing hair follicles can keep producing hair for up to a year.  

Before and after: what’s realistic?

Spironolactone results can vary from person to person, and it is often combined with other approaches and treatments for the best results, including the combined pill, cosmetic hair removal and topical treatments. 

One study demonstrated that spironolactone improved acne in 25% of lean women and 75% of overweight PMOS-affected women after 12 months.* In the UK SAFA trial, 410 adult women with persistent facial acne were assigned spironolactone or placebo. At 24 weeks, 82% of women in the spironolactone group who answered the improvement question reported improvement, compared with 63% in the placebo group. That supports giving acne treatment enough time, but the trial also wasn’t specifically a PMOS study.**

For excess hair, spironolactone won’t remove hairs already present. Hair removal often remains useful alongside treatment. With scalp thinning, stabilising further loss can be a worthwhile result in itself.

To track progress, take monthly photos in similar lighting or note how often you remove facial hair. Daily mirror checks are unlikely to give you a fair comparison.

*Rani, N. et al. (2021). Efficacy of Spironolactone in Adult Acne in Polycystic Ovary Syndrome Patients an Original Research.

**Santer, M. et al. (2023). Effectiveness of spironolactone for women with acne vulgaris (SAFA) in England and Wales: pragmatic, multicentre, phase 3, double blind, randomised controlled trial.

Spironolactone Side Effects and Safety

Spironolactone can cause side effects and may not be suitable for everyone. That’s why a clinician will need to check during a consultation whether it's safe for you. They will ask about your symptoms, any other medications you are taking and your family history. This is especially important because spironolactone is prescribed off-label for PMOS.

Common side effects

Raised blood potassium levels are very common with spironolactone and can affect more than 1 in 10 people.

The common side effects of spironolactone that can affect up to 1 in 10 people who take it are:

• Confusion

• Dizziness

• Feeling sick (nausea)

• Muscle or leg cramps

• Sudden kidney failure

• Excessive growth of breast tissue in men, breast lumps, breast pain

• General weakness*

Women who take spironolactone for PMOS symptoms have also reported the following side effects:

• Low blood pressure

• Needing to pee more often

• Bleeding between periods**

*Electronic Medicines Compendium. (2025). Spironolactone 12.5 mg Film-coated Tablets.

**Armanini, D. et al. (2016). Spironolactone in the treatment of polycystic ovary syndrome.

What to do if you get common side effects

Most spironolactone side effects are mild and can be managed at home.

Serious risks and when to get medical help

Spironolactone can raise potassium levels because it reduces how much potassium your kidneys remove. High potassium, or hyperkalaemia, can affect your heart rhythm, sometimes without obvious warning symptoms.

The risk is higher with kidney disease and certain interacting medications. Before treatment, clinicians commonly check kidney function and potassium to ensure the medication is suitable for you and to monitor how your body responds. You may need repeat tests, but healthy younger women may need fewer checks than someone with kidney problems or interacting medication.

Contact NHS 111 promptly if you develop new muscle weakness, numbness, an irregular heartbeat or severe, persistent dizziness.

Call 999 for collapse, chest pain with palpitations, severe breathing difficulty, or swelling of your tongue or throat.

Pregnancy and contraception

Spironolactone should be avoided for PMOS symptom treatment during pregnancy. Its anti-androgen action could affect a developing baby’s genital development, particularly a male baby. Human pregnancy evidence is limited, so this is a precaution that needs to be taken seriously.

NICE guidance recommends effective contraception whenever pregnancy is possible during anti-androgen treatment. Spironolactone itself provides no contraceptive protection, and irregular periods are not a sign that pregnancy cannot happen.*

Discuss your plans for pregnancy with your clinician before starting spironolactone so that they can help you take it safely. A doctor will usually advise you to stop taking spironolactone at least 1 month before trying to conceive, and will discuss alternative treatments if necessary. 

If you think you’re pregnant while taking spironolactone for PMOS symptoms, stop taking it and contact your doctor promptly.

*NICE. (2026). Polyendocrine metabolic ovarian syndrome (previously known as polycystic ovary syndrome): assessment and management.

Spironolactone and Other PMOS Treatments

Spironolactone can form part of your PMOS treatment plan, depending on which symptoms are affecting you most. Other options target different aspects of the condition, from insulin resistance to irregular periods. Understanding how these treatments work, and when you can use them together, can help you discuss the right options with your clinician. 

Spironolactone with the combined pill

The combined pill and spironolactone can be prescribed together because they work in complementary ways. The pill suppresses ovarian androgen production and increases a protein that binds testosterone, reducing the amount available to act on tissues. Spironolactone blocks androgen activity at receptors. The pill also provides contraception and may help control spironolactone-related irregular bleeding.

The combined pill isn’t suitable for everyone, but your clinician will discuss this with you during your consultation. If you can’t take the combined pill, another effective contraceptive method may be more suitable alongside spironolactone. 

Spironolactone vs other anti-androgen options

Spironolactone is not the only anti-androgen option available for PMOS. Here are some of the options available: 

Spironolactone and metformin

Metformin and spironolactone do different jobs, but they can be taken together to manage the symptoms of PMOS. Metformin addresses the metabolic features of PMOS, such as insulin resistance and blood glucose levels. It can also help promote regular periods in some women. 

Spironolactone targets androgen-related skin and hair symptoms. Neither is universally better, and some women may be prescribed both for different reasons. If insulin resistance is part of your PMOS, understanding that link can help you make sense of a treatment plan involving more than one medicine. 

Non-medical and cosmetic options

Spironolactone is often taken alongside non-medical and cosmetic treatments that can help manage PMOS acne, hair loss and excess hair. Some of the options include:

• Shaving, threading or waxing for immediate hair removal

• Laser treatment for longer-term hair reduction, with suitability depending on hair and skin colour

• Electrolysis to treat individual follicles

• Topical acne treatments alongside an appropriate skincare routine

• Scalp treatments such as minoxidil, where suitable, for female pattern hair loss

If you are taking spironolactone for excess hair, cosmetic hair removal options can help reduce the appearance of hair and boost confidence, especially since it can take up to 18 months for noticeable results. Cosmetic treatments don’t make your symptoms less medical. It simply gives you another way to manage them.

Stopping Spironolactone: What Happens?

If you’re ready to stop spironolactone, perhaps because you feel it is not working for you or want to try for a baby, it’s important to be aware that your symptoms may gradually return once you stop. This is because spironolactone regulates your androgen levels while you’re taking it, so when you stop, they may rise again, and your previous symptoms, such as acne or excess hair growth, may return. 

Talk to your clinician before stopping spironolactone, especially if you have been taking it alongside other treatments such as the combined pill or for another condition, such as fluid retention or high blood pressure. Arrange an appointment with your doctor if:

• You’re planning pregnancy

• Side effects are difficult to manage

• You haven’t noticed worthwhile improvement after an adequate trial of the medication (usually 6 months)

• Your symptoms or priorities have changed

Getting Support for PMOS (PCOS) Symptoms

You don’t need to wait until PMOS symptoms are severe before asking for help. Acne that affects your confidence, daily facial hair removal and worrying scalp changes all deserve a proper conversation.

Take a short symptom history to your appointment outlining what’s changed, what you’ve tried and which symptom matters most to you. Ask your clinician for details on when they'll review your treatment and how you’ll judge whether it’s helping.

Our related guides on PMOS acne, insulin resistance, and thinning hair can help you prepare and better understand what’s happening in your body. Your GP can also assess suspected PMOS and refer you to a specialist when needed.

The aim is to establish a treatment plan that addresses your priorities and fits your health and pregnancy plans.

FAQs

Is metformin or spironolactone better for PMOS?

It depends. Metformin is generally used for metabolic concerns, including insulin resistance, and may help menstrual regularity. Spironolactone targets androgen-related symptoms such as acne and excess hair growth. Your clinician may recommend either medicine, both, or another option according to your symptoms. 

Will I gain weight on spironolactone?

No. Weight gain isn’t an expected treatment effect. If your weight changes unexpectedly, discuss it with your clinician, particularly if you also develop swelling or breathlessness. 

Can spironolactone make your hair grow?

Yes. Spironolactone may help with scalp hair growth in some women with female pattern hair loss, but it is not guaranteed. It can simultaneously slow unwanted facial or body hair because androgens affect follicles differently in different areas. 

Can spironolactone help you lose weight?

No. Weight loss is not an expected side effect of spironolactone. However, because spironolactone removes excess fluid, some people initially notice they weigh less. This is usually water loss, not fat loss, and spironolactone is not a weight loss medication.

Does spironolactone lower androgen levels?

Yes. Spironolactone works by blocking androgen activity, primarily by blocking androgen receptors and lowering testosterone production. This helps to improve acne, oily skin, excess hair growth and scalp hair loss in PMOS patients.