Is finasteride safe? Risks and benefits
What finasteride does, the side effects its leaflet lists, and questions to ask before starting or if something changes.

Wondering if finasteride is safe? Many men take it for hair loss or an enlarged prostate without problems, but it isn’t risk-free.
The UK leaflet warns of depression and suicidal thoughts. It also lists sexual problems that can last after stopping, which patients call post-finasteride syndrome (PFS).
The Propecia leaflet lists “persistent difficulty having an erection after discontinuation of treatment”. It’s easy to miss before you start.
Here is what finasteride does, what the leaflet lists, and what to ask before you start.
What does finasteride do?
Finasteride blocks an enzyme called 5-alpha reductase. That stops the body turning testosterone into a stronger hormone, DHT, which drives male pattern hair loss and prostate growth.
At 1 mg it’s sold as Propecia for hair loss. At 5 mg it’s Proscar, for an enlarged prostate. Both are prescription medicines in the UK.
It works for many men, and many take it for years without trouble. The real question is what you’re told about the risks before you start.
DHT does more than grow hair. It’s also active in the brain, the genitals and the skin, so lowering it can affect more than the scalp.
What side effects does the leaflet list?
The UK Propecia leaflet lists erection problems, lower sex drive and less semen as uncommon, affecting up to 1 in 100 people. Other side effects have no known frequency. They include breast swelling or tenderness, testicular pain, anxiety and male infertility.
On mood, the leaflet says “depressed mood, depression and, less frequently, suicidal thoughts have been reported”. If that happens, it says to stop taking Propecia and contact your doctor. Tell the people close to you that you’re taking it, so they can spot changes too.
If you’re struggling, the Samaritans are free to call on 116 123, day or night.
Breast changes have their own page: finasteride and gynaecomastia. Low mood has another: finasteride and depression.
Can finasteride side effects last after stopping?
Yes, for some people. The leaflet lists lasting problems with erections, sex drive and ejaculation “after discontinuation of treatment”. In 2024 the UK regulator, the MHRA, said sexual problems have “persisted even after treatment was stopped”. It put a warning card in every finasteride pack.
The MHRA had received 426 Yellow Card reports of sexual side effects by April 2024. Reports aren’t a count of how many people are affected. Nobody has measured that yet.
PFS is more than sex. Proposed criteria from 2022 say problems with cognition, depression and suicidal thoughts can come with the sexual changes, or without them.
Sam’s GP suggested finasteride for his hair loss and sent him to the NHS website. He read that erection problems might happen. Was anything said about them lasting? “Nothing permanent,” he says. Watch from 3:56 to hear how little warning he got.
The research is small, and mostly studies men who already have lasting symptoms. It can’t say how common PFS is, but it shows the symptoms go well beyond sex.
One US study from 2012 interviewed 61 former users whose sexual side effects had lasted at least three months, and 29 men who’d never taken it. About 3 in 4 former users had signs of depression, against 1 in 10 of the others.
An Italian team led by Roberto Melcangi found changed levels of brain steroids in the spinal fluid of men with PFS. That may help explain the mood and cognitive problems, though it doesn’t prove a cause.
For what PFS feels like day to day, see our list of PFS symptoms.
What should I ask before starting, or if I have side effects?
Finasteride helps many people. Whether to take it, or stop, is a decision for you and your prescriber. If your mood drops, the leaflet says to stop and see a doctor.
Four questions for your prescriber
- What side effects should I watch for, including mood?
- Can any of them last after I stop?
- What do I do if something changes?
- Who follows me up while I take it?
You could start with: "I've read the leaflet line about problems lasting after stopping. Can we talk about it?"
If you already have symptoms, write down the medicine and dates, for example “Finasteride 1 mg from March 2023, last tablet June 2024”. Then add what changed and when. Our guide on how to talk to your doctor about PFS has more.
Report it: it helps everyone
A doctor’s note helps you. A report to the medicines regulator helps everyone else: it is how patterns get noticed.
- No proof needed. A suspicion is enough, even years after stopping.
- Where: the Yellow Card scheme in the UK, MedWatch in the US. Our Yellow Card guide for finasteride shows each step.
- Use the right words. If symptoms continued after stopping, write Post 5-alpha-reductase inhibitor syndrome (MedDRA 10082430).
Our reporting guide walks you through it
What else do people ask?
Is the 5 mg dose (Proscar) different? It’s the same medicine at a higher dose, mostly for older men. Since 2026, the MHRA tells 5 mg users to contact their doctor as soon as possible if they get depression or suicidal thoughts. Our page on Proscar side effects covers it.
Is topical finasteride safer? It’s applied to the scalp, but some still reaches the blood. Nobody has shown that it avoids lasting side effects. Our page on topical finasteride explains what’s known.
What are the other options for hair loss? There are other treatments, each with its own risks. We don’t recommend any medicine. Our comparison of finasteride, minoxidil and dutasteride sets out what each leaflet says.
Sam was told about erection problems, but “nothing permanent”. If yours have lasted, read our PFS page and report it.
Sources
- Propecia 1 mg film-coated tablets: patient information leaflet, last revised May 2026, electronic medicines compendium (emc). Section 2: “Mood alterations such as depressed mood, depression and, less frequently, suicidal thoughts have been reported”; stop and contact a doctor. Section 4: erection problems, reduced sex drive and reduced semen volume “Uncommon (may affect up to 1 in 100 people)”; persistent erection, sex drive and ejaculation problems “after discontinuation of treatment” under “Frequency unknown”.
- MHRA, Finasteride: reminder of the risk of psychiatric side effects and of sexual side effects (which may persist after discontinuation of treatment), Drug Safety Update, 29 April 2024. 426 Yellow Card reports of sexual dysfunction up to 5 April 2024; patient card in all packs.
- MHRA, Finasteride and dutasteride: updated safety warnings for psychiatric side effects and sexual dysfunction, Drug Safety Update, 11 May 2026.
- Healy D, Bahrick A, Bak M and colleagues. Diagnostic criteria for enduring sexual dysfunction after treatment with antidepressants, finasteride and isotretinoin. Int J Risk Saf Med 2022;33(1):65-76. Proposed criteria from expert agreement. Section 5: cognitive impairment, depression and suicidality “can occur independently of any sexual difficulties but may also accompany sexual problems”.
- Irwig MS. Depressive symptoms and suicidal thoughts among former users of finasteride with persistent sexual side effects. J Clin Psychiatry 2012. 61 former users with sexual side effects lasting 3 months or more, against 29 controls: depressive symptoms 75% against 10%; suicidal thoughts 44% against 3%. Small, selected sample, US.
- Melcangi RC and colleagues. Neuroactive steroid levels and psychiatric and andrological features in post-finasteride patients. J Sex Med 2013;10(10):2598-2603.
- Rahimi-Ardabili B and colleagues. Finasteride induced depression: a prospective study. BMC Clin Pharmacol 2006;6:7.
- GOV.UK, Report a problem with a medicine or medical device.
- Moral Medicine, The Hidden Devastation of Finasteride, Sam’s Story, June 2025. Sam’s warning from 3:56; “nothing permanent” at 4:32.
Sources checked on 22 October 2026. AI-assisted writing and review, not clinical review.
Lasting side effects after finasteride?
Make them count.
Our step-by-step guide finds the form for your country.
Finasteride: what the official texts say, country by country
For the 5α-reductase inhibitor finasteride (Propecia), the product information we read in the United Kingdom, in the United States, in Canada, in Australia, in New Zealand, in Germany, in France, in Italy, in Spain, in Brazil and in India, in some places that of another product, lists sexual dysfunction that continued after treatment was stopped. In each of those texts it stands among side effects reported once the medicine was in general use. Several add that these reports come from a group of unknown size, so how often this happens, and whether finasteride is the cause, cannot always be established. Patients call lasting effects after finasteride post-finasteride syndrome (PFS). The wording a European Commission decision set for the EU in 2025 is about mood and thoughts of suicide, and has no sentence about sexual side effects continuing after the medicine is stopped.
This is a record of what each text says and of the date it prints. A text is quoted in its own words, or summarised where the row says so. It is not a comparison of countries. All medicines and countries
Finasteride: the official texts, country by country (85 texts read)
| Country or region | What the text says | Document | Dates |
|---|---|---|---|
| United Kingdom | Sexual side effects, as listed4.8 Undesirable effects · Psychiatric disorders: · Uncommon*: Sexual side effects, as listed4.8 Undesirable effects · Reproductive system and breast disorders: · Uncommon*: Sexual side effects that continue after stopping4.8 Undesirable effects The same text also says4.8 Undesirable effects Sexual side effects, as listed4.8 Undesirable effects Sexual side effects, as listed4.8 Undesirable effects This text also has a warning about changes in mood that names sexual dysfunction as something that may contribute to them. That warning says nothing about sexual side effects continuing after stopping. It is not reproduced here, because this record shows the sexual side effects a text lists and whether it says they continue after stopping. The document link in this row opens the text. Texts for other products in this country do not all say the same. The ones we read are on the full record. | Text for professionals Summary of Product Characteristics (SmPC): Propecia 1 mg Film-Coated TabletsPropecia 1 mg film-coated tablets, Organon Pharma (UK) Limited · Read in a compendium of product information: emcAlso on record: 1 more text for professionals, with such a sentence; 2 patients' leaflets, with such a sentence; 5 related documents, with such a sentence; 5 related documents, with no such sentence | Text revisedChecked |
| European Union | This text has no sentence about sexual side effects continuing after the medicine is stopped. This text also has a warning about changes in mood that names sexual dysfunction as something that may contribute to them. That warning says nothing about sexual side effects continuing after stopping. It is not reproduced here, because this record shows the sexual side effects a text lists and whether it says they continue after stopping. The document link in this row opens the text. This is wording for national product texts. There is no single EU product text for this medicine. | Document from the regulator Finasteride- and dutasteride-containing medicinal products, Article 31 referral: Annex III Amendments to relevant sections of the Product InformationRead on the regulator's site: European Medicines AgencyAlso on record: 2 more related documents, with no such sentence | The text prints no dateChecked |
| United States | Sexual side effects that continue after stopping6 ADVERSE REACTIONS · 6.2 Postmarketing Experience The same text also says6 ADVERSE REACTIONS · 6.2 Postmarketing Experience This sentence stands in the list of adverse reactions. The warnings section of this text has no entry on sexual function. Texts for other products in this country do not all say the same. The ones we read are on the full record. This text names sexual side effects in several places that this row does not show. Together those passages are too long to reproduce here. The document link in this row opens the text. That they are not shown says nothing about how common these side effects are. On 14 October 2026 we searched the labels in openFDA, the FDA's open database. A sentence that sexual dysfunction continued after treatment was stopped stood on 151 of the 181 labels in that database that name finasteride, and on each of them among the adverse reactions, in no warnings section. Of the 30 without it, 10 are hair products with labels in the Drug Facts style, 5 are listings of compounded solutions for the skin, 2 have no text on adverse reactions, and 13 are older labels of 5 mg tablets with an earlier list of adverse reactions. A table cell or list line is shown whole, as the text prints it. Some of them also name side effects that are not sexual. | Text for professionals PROPECIA® (finasteride) tablets for oral use: Full Prescribing InformationPropecia tablets 1 mg, Organon LLC · Read in the government's medicines database: DailyMedAlso on record: 1 more text for professionals, with such a sentence; 2 patients' leaflets, with such a sentence; 2 related documents, with such a sentence; 3 related documents, with no such sentence | Text revisedChecked |
| Canada | Sexual side effects that continue after stopping8 ADVERSE REACTIONS · 8.5 Post-Market Adverse Reactions Sexual side effects that continue after stopping8 ADVERSE REACTIONS · 8.5 Post-Market Adverse Reactions The same text also says8 ADVERSE REACTIONS · 8.5 Post-Market Adverse Reactions This sentence stands in the list of adverse reactions. The warnings section of this text has no entry on sexual function. Texts for other products in this country do not all say the same. The ones we read are on the full record. This text names sexual side effects in several places that this row does not show. Together those passages are too long to reproduce here. The document link in this row opens the text. That they are not shown says nothing about how common these side effects are. A table cell or list line is shown whole, as the text prints it. Some of them also name side effects that are not sexual. | Text for professionals PRODUCT MONOGRAPH INCLUDING PATIENT MEDICATION INFORMATION: PrPROPECIA® finasteride tablets, Film-coated Tablets 1 mg, USPPropecia film-coated tablets 1 mg, Organon Canada Inc. · Read in the regulator's own database: Drug Product DatabaseAlso on record: 1 more text for professionals, with such a sentence; 2 patients' leaflets, with such a sentence; 2 related documents, with no such sentence | Text revisedChecked |
| Australia | Sexual side effects that continue after stoppingSection 4.8 · Post-marketing experienceIn section 4.8, under post-marketing experience, Australia's product information for Propecia lists a lower sex drive, and sexual dysfunction (erection and ejaculation problems), each as having gone on after the treatment was stopped.Summarised, not quoted, because of the TGA's access terms. The same text also saysSection 4.8 · Post-marketing experienceThe text says these reports come from a group of unknown size, so how often this happens, and whether the medicine is the cause, cannot always be established.Summarised, not quoted, because of the TGA's access terms. The regulator's site asks readers to accept its terms before it shows this text. This text also has a warning about changes in mood that names sexual dysfunction as something that may contribute to them. That warning says nothing about sexual side effects continuing after stopping. It is not reproduced here, because this record shows the sexual side effects a text lists and whether it says they continue after stopping. The document link in this row opens the text. Texts for other products in this country do not all say the same. The ones we read are on the full record. | Text for professionals AUSTRALIAN PRODUCT INFORMATION PROPECIA (finasteride) TabletsPROPECIA, Organon Pharma Pty Ltd · Read in the regulator's own database: TGA eBSAlso on record: 1 more text for professionals, with such a sentence; 2 patients' leaflets, with such a sentence | Text revisedChecked |
| New Zealand | Sexual side effects, as listed4.8 Undesirable effects · Adverse events identified during clinical trials The same text also says4.8 Undesirable effects · Adverse events identified during clinical trials Sexual side effects that continue after stopping4.8 Undesirable effects · Adverse events identified during postmarketing experience · Psychiatric disorders: Sexual side effects that continue after stopping4.8 Undesirable effects · Adverse events identified during postmarketing experience · Reproductive system and breast disorders: The same text also says4.8 Undesirable effects · Adverse events identified during postmarketing experience This sentence stands in the list of adverse reactions. The warnings section of this text has no entry on sexual function. Texts for other products in this country do not all say the same. The ones we read are on the full record. | Text for professionals New Zealand Data Sheet, PROPECIAPropecia 1 mg film coated tablet, Organon (New Zealand) Limited · Read in the regulator's own database: MedsafeAlso on record: 1 more text for professionals, with such a sentence; patients' leaflet, with such a sentence; related document, with such a sentence | Text revisedChecked |
| Germany | Sexual side effects, as listed4.8 Nebenwirkungen · Psychiatrische Erkrankungen: · Gelegentlich* Sexual side effects, as listed4.8 Nebenwirkungen · Erkrankungen der Geschlechtsorgane und der Brustdrüse: · Gelegentlich* Sexual side effects that continue after stopping4.8 Nebenwirkungen The same text also says4.8 Nebenwirkungen Sexual side effects, as listed4.8 Nebenwirkungen This is the holder's own copy. The regulator's database asks visitors to accept its terms first, which we did not do. This text also has a warning about changes in mood that names sexual dysfunction as something that may contribute to them. That warning says nothing about sexual side effects continuing after stopping. It is not reproduced here, because this record shows the sexual side effects a text lists and whether it says they continue after stopping. The document link in this row opens the text. Texts for other products in this country do not all say the same. The ones we read are on the full record. | Text for professionals Fachinformation (Zusammenfassung der Merkmale des Arzneimittels)Propecia® 1 mg Filmtabletten, Organon Healthcare GmbH · Read on the holder's own site: Organon Healthcare GmbHAlso on record: 1 more text for professionals, with such a sentence; 2 patients' leaflets, with such a sentence; patients' leaflet, with no such sentence; 2 related documents, with such a sentence; related document, with no such sentence | Text revisedChecked |
| France | Sexual side effects, as listed4.8. Effets indésirables · Affections psychiatriques · Peu fréquent* Sexual side effects, as listed4.8. Effets indésirables · Affections des organes de reproduction et du sein · Peu fréquent* Sexual side effects that continue after stopping4.8. Effets indésirables The same text also says4.8. Effets indésirables Sexual side effects, as listed4.8. Effets indésirables The text itself prints no date of revision. An official list of medicines we read shows the originator product as cancelled, revoked or archived. This is the text of another product, the one named in this row. This text also has a warning about changes in mood that names sexual dysfunction as something that may contribute to them. That warning says nothing about sexual side effects continuing after stopping. It is not reproduced here, because this record shows the sexual side effects a text lists and whether it says they continue after stopping. The document link in this row opens the text. Texts for other products in this country do not all say the same. The ones we read are on the full record. | Text for professionals Résumé des Caractéristiques du ProduitFINASTERIDE ARROW LAB 1 mg, comprimé pelliculé, ARROW GENERIQUES · Read in the government's medicines database: Base de données publique des médicamentsAlso on record: 1 more text for professionals, with such a sentence; 2 patients' leaflets, with such a sentence; patients' leaflet, with no such sentence; 9 related documents, with such a sentence; 3 related documents, with no such sentence | Updated by the regulatorChecked |
| Italy | Sexual side effects, as listed4.8 Effetti indesiderati · Disturbi psichiatrici: · Non comune* Sexual side effects, as listed4.8 Effetti indesiderati · Patologie dell’apparato riproduttivo e della mammella: · Non comune* The same text also says4.8 Effetti indesiderati Sexual side effects that continue after stopping4.8 Effetti indesiderati Sexual side effects, as listed4.8 Effetti indesiderati The text itself prints no date of revision. This text also has a warning about changes in mood that names sexual dysfunction as something that may contribute to them. That warning says nothing about sexual side effects continuing after stopping. It is not reproduced here, because this record shows the sexual side effects a text lists and whether it says they continue after stopping. The document link in this row opens the text. Texts for other products in this country do not all say the same. The ones we read are on the full record. | Text for professionals Riassunto delle caratteristiche del prodottoPropecia 1 mg compresse rivestite con film, Organon Italia S.r.l. · Read in the regulator's own database: Banca Dati FarmaciAlso on record: 1 more text for professionals, with such a sentence; 2 patients' leaflets, with such a sentence; 2 related documents, with such a sentence; 2 related documents, with no such sentence | Made available by the regulatorChecked |
| Spain | Sexual side effects, as listed4.8. Reacciones adversas · Trastornos psiquiátricos: · Poco frecuentes* Sexual side effects, as listed4.8. Reacciones adversas · Trastornos del aparato reproductor y de la mama: · Poco frecuentes* The same text also says4.8 Reacciones adversas Sexual side effects that continue after stopping4.8. Reacciones adversas Sexual side effects, as listed4.8. Reacciones adversas This text also has a warning about changes in mood that names sexual dysfunction as something that may contribute to them. That warning says nothing about sexual side effects continuing after stopping. It is not reproduced here, because this record shows the sexual side effects a text lists and whether it says they continue after stopping. The document link in this row opens the text. Texts for other products in this country do not all say the same. The ones we read are on the full record. | Text for professionals Ficha técnicaPropecia 1 mg comprimidos recubiertos con película, Organon Salud, S.L. · Read in the regulator's own database: CIMAAlso on record: 1 more text for professionals, with such a sentence; 2 patients' leaflets, with such a sentence; patients' leaflet, with no such sentence; related document, with no such sentence | Text revisedChecked |
| Brazil | Sexual side effects, as listed8. QUAIS OS MALES QUE ESTE MEDICAMENTO PODE ME CAUSAR? · Reação comum (ocorre entre 1% e 10% dos pacientes que utilizam este medicamento): Sexual side effects, as listed8. QUAIS OS MALES QUE ESTE MEDICAMENTO PODE ME CAUSAR? · Reação incomum (ocorre entre 0,1% e 1% dos pacientes que utilizam este medicamento): The same text also says8. QUAIS OS MALES QUE ESTE MEDICAMENTO PODE ME CAUSAR? Sexual side effects that continue after stopping8. QUAIS OS MALES QUE ESTE MEDICAMENTO PODE ME CAUSAR? · Frequência desconhecida: durante a comercialização do medicamento, as seguintes reações foram relatadas voluntariamente, não sendo possível estimar o tamanho da população exposta: Sexual side effects that continue after stopping8. QUAIS OS MALES QUE ESTE MEDICAMENTO PODE ME CAUSAR? · Frequência desconhecida: durante a comercialização do medicamento, as seguintes reações foram relatadas voluntariamente, não sendo possível estimar o tamanho da população exposta: Sexual side effects that continue after stopping8. QUAIS OS MALES QUE ESTE MEDICAMENTO PODE ME CAUSAR? · Frequência desconhecida: durante a comercialização do medicamento, as seguintes reações foram relatadas voluntariamente, não sendo possível estimar o tamanho da população exposta: This is the holder's own copy. The regulator's database refused our requests (it blocks by country; we asked from Denmark). An official list of medicines we read shows the originator product as cancelled, revoked or archived. This is the text of another product, the one named in this row. Texts for other products in this country do not all say the same. The ones we read are on the full record. | Patient leaflet finasterida, EMS S/A, comprimido revestido 1 mg: bula para o pacienteFinasterida 1 mg comprimido revestido, EMS S/A · Read on the holder's own site: Sara – Plataforma Oficial de Bulas Digitais de Medicamentos do Grupo EMSAlso on record: 2 texts for professionals, could not be opened; 3 more patients' leaflets, with such a sentence; 2 more patients' leaflets, could not be opened | Text approvedChecked |
| India | Sexual side effects that continue after stoppingUndesirable Effects · Postmarketing Experience · Reproductive System: The same text also saysUndesirable Effects · Postmarketing Experience This is the holder's own copy. This regulator publishes no database of such texts. This sentence stands in the list of adverse reactions. The warnings section of this text has no entry on sexual function. Texts for other products in this country do not all say the same. The ones we read are on the full record. This text names sexual side effects in several places that this row does not show. Together those passages are too long to reproduce here. The document link in this row opens the text. That they are not shown says nothing about how common these side effects are. A table cell or list line is shown whole, as the text prints it. Some of them also name side effects that are not sexual. | Text for professionals FINPECIA TabletsFinpecia tablets (finasteride IP 1 mg, film-coated), Cipla Ltd. · Read on the holder's own site: Cipla (ciplamed.com)Also on record: 1 more text for professionals, with such a sentence | Text revisedChecked |
Brand names
These are the brand names of finasteride we saw in the official lists, compendia and regulators' pages we opened on or after 14 October 2026. A country may have more.
- Propecia
- United Kingdom, United States, Canada, New Zealand, Germany, Italy, Spain
- Proscar
- United Kingdom, United States, Canada, Germany, Italy, Spain
- Chibro-Proscar
- France
- Ricit
- New Zealand
- Prostide
- Italy
- Genaprost
- Italy
- Finastid
- Italy
- Asterid
- Italy
- Ridestin
- Italy
- Finestar
- Italy
- Fendazel
- Italy
- Stecur
- Italy
- Sitas
- Italy
- Finacapil
- Italy
- Ormicton
- Italy
- Carefinast
- Italy
- Finedor
- Italy
- Terip
- Italy
- Alocare
- Spain
- Litace
- Spain
- Maxpil
- Spain
- Excalv
- Brazil
- Finalop
- Brazil
- Finarid
- Brazil
- Finastil
- Brazil
- Prohair
- Brazil
What is not known
- How often PFS happens is unknown. The UK text for professionals says the frequency of the side effects reported after marketing, among them sexual dysfunction that persisted after treatment was stopped, “cannot be determined”, because they come from spontaneous reports. (source)
Code and reporting
In a report to a medicines regulator, the term is Post 5-alpha-reductase inhibitor syndrome (MedDRA code 10082430). Where to report, country by country
Every row in this table was checked on or after . To quote this record, name SIDEfxHUB and give this page's address. All medicines and countries · The whole record as a file: JSON · CSV · How these texts are checked
You may reuse this record under CC BY 4.0 if you credit SIDEfxHUB and give this page's address. The licence covers our compilation, not the texts quoted in it, in the original or in our translation, and not the article above.