Low-dose finasteride: fewer side effects?

Planning to halve your finasteride, or take it every other day? What dose studies show, and what they can't tell you about lasting side effects.

Hoping a smaller dose of finasteride, such as half a tablet or one every other day, will be safer? Nobody has shown that a lower dose prevents side effects that last after you stop. Those lasting effects are called post-finasteride syndrome (PFS), and some men say it began after very small amounts.

Some hair-loss clinic blogs and forums suggest taking less to avoid side effects. None of the ones we read cites a study of what happens after the last tablet.

Nathan had heard the stories, so he waited a month before taking his finasteride. Then he chose what he calls “the very very low dose”: half a tablet, three times a week. He took two.

An extract from Nathan's interview with Moral Medicine, March 2025, from 4:47 to 7:38, in English. He describes the night of his second half tablet and the months after. The views are his own.

“I thought this was going to be like super safe,” he says. After his second half tablet, he woke in the night drenched in sweat. He couldn’t feel emotions or pleasure, and for about a month he could barely leave his bed.

Does a smaller dose change anything, even while you’re still taking it?

Do lower doses of finasteride cause fewer side effects?

Not clearly, even while you’re taking it. A 2026 review looked at a hair-loss trial that compared doses. Men on a fifth of a tablet reported no fewer sexual side effects than men on a whole one. On every dose, the numbers were close to placebo, a dummy tablet.

The UK medicines regulator’s 2024 safety review links the lower 1 mg hair-loss dose to more side effects than the 5 mg prostate dose. It says nobody knows why. And most men on 1 mg are young, treating hair loss.

Two blister strips of finasteride 1 mg tablets, one printed Finasteride Tablets USP 1 mg, the other holding small round blue tablets — Generic finasteride 1 mg tablets, made in India. The 1 mg tablet is the hair-loss dose, and the one some men cut in half. Photo: Generic Propecia by Kristoferb at English Wikipedia, CC BY-SA 3.0, via Wikimedia Commons; scaled down.

The UK leaflet lists erection problems and a lower sex drive that carried on after stopping. It names no dose too small for that.

PFS isn’t only about sex. A checklist proposed in 2022 by doctors and researchers says PFS can also mean problems with concentration and memory, depression and suicidal thoughts, sometimes with no sexual problems at all. If you’re struggling, call Samaritans on 116 123.

In October 2026 we found no study that followed men on low and usual doses after they stopped. The dose trials lasted about a year.

The story in 3 lines

A fifth of a 1 mg tablet lowered DHT, the hormone finasteride targets, almost as much as a whole one. A smaller dose still changes it, so it isn't clearly gentler (Drake and colleagues, 1999).
The UK leaflet lists sexual problems that carried on after stopping. It names no dose that rules this out.
We found no study showing a low dose prevents this (October 2026). Patients call it PFS.

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Does half a finasteride tablet lower DHT less?

Only a little. Finasteride lowers DHT, a hormone made from testosterone and linked to male hair loss. A 1999 trial gave men one of five daily doses for six weeks.

A fifth of the 1 mg tablet lowered blood DHT almost as much as a whole one. Even a twentieth cut it by about half. Half a tablet wasn’t tested, but it sits between a fifth and a whole one.

How much DHT in the blood fell after six weeks, by daily dose

5 mg, the prostate doseabout seven in ten

1 mg, the hair-loss doseabout seven in ten

A fifth of a 1 mg tabletabout seven in ten

A twentieth of a 1 mg tabletabout half

Average fall in blood DHT in a trial of men with hair loss. It shows only how much the hormone changed, not hair growth, side effects or whether they lasted. Source: Drake and colleagues, 1999.

Nobody knows yet whether lower DHT is what causes PFS. But cutting a tablet in half doesn’t halve its effect on DHT.

Does taking finasteride every other day help?

We found no study on whether it means fewer side effects. A 1996 review found a single dose keeps DHT down for up to four days. How long finasteride stays in your system explains why.

Shaun took 1 mg every other day. After three or four weeks, he says, his orgasms felt muted and his genitals went numb, so he stopped.

Chirag went lower still. After side effects on a full tablet, he decided he’d simply taken too much. Here he explains what he took next.

An extract from Chirag's interview with Moral Medicine, March 2025, from 5:00 to 6:50, in English. He describes going back on a much lower dose, three times a week, and stopping again. The views are his own.

At first he felt fine, apart from “maybe a little bit less libido”. Months later his morning erections stopped, so he quit. About six months after that, he says, “something just turned off”. His story tells the rest.

PFS after a few pills is about a handful of tablets. A spray puts less finasteride in your blood, but not none, as topical finasteride explains.

What can I do?

Finasteride helps many men keep their hair. What to do about side effects is a decision for you and your prescriber. If you feel low or have suicidal thoughts, the UK leaflet says to stop taking it and contact your doctor.

If something changed, a low dose isn’t a reason to brush it off. Write down your dose and dates: “Finasteride 1 mg, half a tablet on 3 and 5 March 2026, then stopped. Genitals numb since 20 March.”

Three questions for your prescriber

Could this be the lasting effect the leaflet describes, even at my dose?
What else could explain it, and how would we check?
Can you record finasteride, my dose and my dates in my notes?

You could start with: “I only took a small dose, but something changed and it hasn't gone back.”

Bring the leaflet. You can report it without a doctor agreeing.

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?

Does finasteride 0.5 mg cause side effects? It may. In trials, men on even smaller doses reported sexual side effects, at rates close to placebo. Nathan’s problems began on half a tablet.

I’m on a low dose and feel fine. Can problems start after I stop? Some men say so. The 2022 checklist says a lasting problem may only appear once the medicine is stopped. Chirag’s biggest change came months after his last dose. More on stopping finasteride.

Do side effects on a low dose go away? In trials of the 1 mg tablet, most sexual side effects were mild and eased after stopping, the 2026 review found. The NHS says they can sometimes carry on. Nobody knows yet who will be affected.

Nathan thought half a tablet would be “super safe”. A year and four months on, he said things had improved, but “it feels like I’m hung over every day, some days are better, some days are worse”. If a low dose changed something for you, read about PFS and report it with your dose and dates.

Sources

Propecia 1 mg film-coated tablets, patient information leaflet, electronic medicines compendium (emc), last revised May 2026. Section 4 lists “persistent difficulty having an erection after discontinuation of treatment”. It also lists a persistent decrease in sex drive and persistent problems with ejaculation after discontinuation. No line ties these to a dose. Section 3: “The recommended dose is one tablet each day.” Section 2: for low mood or suicidal thoughts, “stop taking Propecia and contact your doctor for further medical advice”.
Drake L, Hordinsky M, Fiedler V and colleagues. The effects of finasteride on scalp skin and serum androgen levels in men with androgenetic alopecia. J Am Acad Dermatol 1999;41(4):550-4. Abstract read. 249 men took 0.01, 0.05, 0.2, 1 or 5 mg a day, or placebo, for 42 days. Serum DHT fell by 49.5%, 68.6%, 71.4% and 72.2% on 0.05, 0.2, 1 and 5 mg. “Doses of finasteride as low as 0.2 mg per day maximally decreased both scalp skin and serum DHT levels.” It measured DHT, not side effects.
Steiner JF. Clinical pharmacokinetics and pharmacodynamics of finasteride. Clin Pharmacokinet 1996;30(1):16-27. Abstract read: “A single dose of finasteride suppresses serum DHT levels for up to 4 days”. Its half-life in the blood is 4.7 to 7.1 hours. The same abstract says doses below 0.5 mg a day “do not produce much suppression”. The later trial in men with hair loss (source 2) measured otherwise.
Złotowska A, Jastrząb-Miśkiewicz B, Krajewski PK. Sexual dysfunction associated with 5α-reductase inhibitors in the treatment of androgenetic alopecia: a systematic review. Front Med 2026;13:1787706. Full text read (PMC13322902). Section 3.2 covers the dose-ranging trial by Roberts and colleagues (J Am Acad Dermatol 1999;41(4):555-63). Drug-related sexual side effects: 4.3% on 1 mg, 6.1% on 0.2 mg, 1.7% on 0.01 mg. The review says they “did not show a dose-dependent pattern” and were “generally comparable to placebo”. Its table 1 gives a Japanese trial (Kawashima 2004, 48 weeks): decreased libido 2.9% on 1 mg, 1.5% on 0.2 mg, 2.2% on placebo. Abstract: in the 1 mg trials, most sexual side effects were “mild and reversible upon discontinuation”.
MHRA, Safety review of finasteride: public assessment report, April 2024. Section 5.1: “In general, the lower dose of finasteride 1 mg is associated with a higher risk of all side effects, compared to the 5 mg dose.” It adds: “The exact reason for this difference is unknown”. Men on 1 mg “usually are young men using finasteride for hair loss”, and for some “hair loss may be the cause, or lead to depressive symptoms”. Section 5.2, on Yellow Card reports: a different number of reports for the two doses “does not necessarily mean a different level of risk”.
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. Section 5 lists cognitive impairment, depression and suicidality as finasteride effects “that can occur independently of any sexual difficulties”. Section 9: a lasting problem “may only appear when the drug is stopped”. The paper sets no minimum dose.
Our search: Europe PMC, 28 October 2026, for post-finasteride syndrome or persistent sexual side effects of finasteride together with dose, low dose or alternate-day dosing. It gave 131 results; we scanned the titles and read the likely abstracts. No study compared lasting side effects after stopping between men on low and usual doses.
Moral Medicine, This Man Took Finasteride Twice, interview with Nathan, 31 March 2025, from the automatic captions. Embedded from 4:47 to 7:38. A month before taking it (4:23 to 4:37). “The very very low dose”, three times a week, half a pill (4:47 to 4:57). “Super safe” (5:04). The crash after the second dose (5:32 to 5:47). Couldn’t feel emotions or pleasure (5:52, 6:49). Bed-bound for a month (6:27 to 6:57). A year and four months off it, with things improved (7:06 to 7:38). “Hung over every day” (10:13). His story: Nathan’s story.
Moral Medicine, Doctors Said Post-Finasteride Syndrome Wasn’t Real, interview with Chirag, 25 March 2025, from the automatic captions. Embedded from 5:00 to 6:50. Side effects after 10 days, then the belief it was a “dosing issue” (5:02 to 5:40). Back on in June 2023 at a much lower dose, three times a week (5:51 to 5:57). “A little bit less libido” (6:02). Morning erections gone, stopped on 1 January 2024 (6:32 to 6:48). “Something just turned off” on 9 July 2024 (9:00). His story: Chirag’s story.
Moral Medicine, interview with Shaun, 14 September 2024, from the automatic captions. 1 mg every other day (4:41). Nothing for three or four weeks (4:47). Muted orgasm and genital numbness (4:55 to 5:03). Stopped (5:10). His story: Shaun’s story.
NHS, Side effects of finasteride, last reviewed 2 August 2023. Sexual side effects “can sometimes carry on even after you stop taking finasteride”. The page says nothing about dose.
Photo: Generic Propecia by Kristoferb at English Wikipedia, 2010, CC BY-SA 3.0, via Wikimedia Commons. Scaled down.

Sources checked on 28 October 2026. AI-assisted writing and review, not clinical review.

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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)

Finasteride: what each text says about sexual side effects, and about side effects that continue after stopping.
Country or region	What the text says	Document	Dates
United Kingdom	Sexual side effects, as listed4.8 Undesirable effects · Psychiatric disorders: · Uncommon:Decreased libido. Sexual side effects, as listed4.8 Undesirable effects · Reproductive system and breast disorders: · Uncommon:Erectile dysfunction, ejaculation disorder (including decreased volume of ejaculate). Sexual side effects that continue after stopping4.8 Undesirable effectsIn addition, the following have been reported in post-marketing use: persistence of sexual dysfunction (decreased libido, erectile dysfunction and ejaculation disorder) after discontinuation of treatment with 'Propecia'; male breast cancer (see 4.4 Special warnings and precautions for use). The same text also says4.8 Undesirable effectsThe frequency of adverse reactions reported during post-marketing use cannot be determined as they are derived from spontaneous reports. Sexual side effects, as listed4.8 Undesirable effectsIn these studies, the following drug-related adverse experiences were reported in ≥1% of men treated with 'Propecia': decreased libido ('Propecia', 1.8% vs. placebo, 1.3%) and erectile dysfunction (1.3%, 0.7%). In addition, decreased volume of ejaculate was reported in 0.8% of men treated with 'Propecia' and 0.4% of men treated with placebo. Resolution of these side effects occurred in men who discontinued therapy with 'Propecia' and in many who continued therapy. The effect of 'Propecia' on ejaculate volume was measured in a separate study and was not different from that seen with placebo. Sexual side effects, as listed4.8 Undesirable effectsDrug-related sexual undesirable effects were more common in the finasteride 1 mg-treated men than the placebo-treated men, with frequencies during the first 12 months of 3.8% vs 2.1%, respectively. The incidence of these effects decreased to 0.6% in finasteride 1 mg-treated men over the following four years. Approximately 1% of men in each treatment group discontinued due to drug-related sexual adverse experiences in the first 12 months, and the incidence declined thereafter. 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 revised29 Jun 2026Checked14 Oct 2026
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 dateChecked14 Oct 2026
United States	Sexual side effects that continue after stopping6 ADVERSE REACTIONS · 6.2 Postmarketing ExperienceReproductive System: sexual dysfunction that continued after discontinuation of treatment, including erectile dysfunction, libido disorders, ejaculation disorders, and orgasm disorders; male infertility and/or poor seminal quality (normalization or improvement of seminal quality has been reported after discontinuation of finasteride); testicular pain; hematospermia. The same text also says6 ADVERSE REACTIONS · 6.2 Postmarketing ExperienceThe following adverse reactions have been identified during post approval use of PROPECIA. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure: 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 revisedAug 2022Checked14 Oct 2026
Canada	Sexual side effects that continue after stopping8 ADVERSE REACTIONS · 8.5 Post-Market Adverse ReactionsPsychiatric disorders: mood alterations and depression, decreased libido that continued after discontinuation of treatment. Sexual side effects that continue after stopping8 ADVERSE REACTIONS · 8.5 Post-Market Adverse ReactionsReproductive system and breast disorders: sexual dysfunction (erectile dysfunction and ejaculation disorders) that continued after discontinuation of treatment, breast tenderness and enlargement, male breast cancer, testicular pain, hematospermia, male infertility and/or poor seminal quality. The same text also says8 ADVERSE REACTIONS · 8.5 Post-Market Adverse ReactionsBecause these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate the frequency or establish a causal relationship to drug exposure. 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 revised24 Nov 2023Checked14 Oct 2026
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 revised2 Sept 2026Checked14 Oct 2026
New Zealand	Sexual side effects, as listed4.8 Undesirable effects · Adverse events identified during clinical trialsIn these studies, the following medicine-related adverse experiences were reported in ≥ 1% of men treated with PROPECIA: • decreased libido (PROPECIA, 1.8% vs. placebo, 1.3%) • erectile dysfunction (1.3%, 0.7%). In addition, decreased volume of ejaculate was reported in 0.8% of men treated with PROPECIA and 0.4% of men treated with placebo. The same text also says4.8 Undesirable effects · Adverse events identified during clinical trialsResolution of these adverse effects occurred in men who discontinued therapy with PROPECIA and in many who continued therapy. In a separate study, the effect of PROPECIA on ejaculate volume was measured and was not different from that seen with placebo. The incidence of each of the above adverse effects decreased to ≤ 0.3% by the fifth year of treatment with PROPECIA. Sexual side effects that continue after stopping4.8 Undesirable effects · Adverse events identified during postmarketing experience · Psychiatric disorders:decreased libido that continued after discontinuation of treatment. Sexual side effects that continue after stopping4.8 Undesirable effects · Adverse events identified during postmarketing experience · Reproductive system and breast disorders:sexual dysfunction (erectile dysfunction and ejaculation disorders) that continued after discontinuation of treatment The same text also says4.8 Undesirable effects · Adverse events identified during postmarketing experienceBecause these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate the frequency or establish a causal relationship to drug exposure. 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 revised11 Dec 2023Checked14 Oct 2026
Germany	Sexual side effects, as listed4.8 Nebenwirkungen · Psychiatrische Erkrankungen: · Gelegentlichverminderte LibidoOriginal text: German. Our translation:decreased libido Sexual side effects, as listed4.8 Nebenwirkungen · Erkrankungen der Geschlechtsorgane und der Brustdrüse: · Gelegentlicherektile Dysfunktion, Ejakulationsstörung (einschl. vermindertes Ejakulatvolumen)Original text: German. Our translation:erectile dysfunction, ejaculation disorder (including decreased volume of ejaculate) Sexual side effects that continue after stopping4.8 NebenwirkungenNach Markteinführung wurde zusätzlich über Folgendes berichtet: Persistenz von sexueller Dysfunktion (verminderte Libido, erektile Dysfunktion und Ejakulationsstörungen) nach dem Absetzen von Finasterid; Brustkrebs beim Mann (siehe Abschnitt 4.4 Besondere Warnhinweise und Vorsichtsmaßnahmen für die Anwendung).Original text: German. Our translation:In addition, the following has been reported after marketing: persistence of sexual dysfunction (decreased libido, erectile dysfunction and ejaculation disorders) after finasteride has been stopped; breast cancer in men (see section 4.4 Special warnings and precautions for use). The same text also says4.8 NebenwirkungenDie Häufigkeit der nach Markteinführung berichteten unerwünschten Ereignisse kann nicht bestimmt werden, da es sich um Spontanberichte handelt.Original text: German. Our translation:The frequency of the adverse events reported after marketing cannot be determined, as they come from spontaneous reports. Sexual side effects, as listed4.8 NebenwirkungenMit einer Häufigkeit von 3,8 % bzw. 2,1 % während der ersten 12 Monate waren sexuelle Nebenwirkungen bei den mit Finasterid behandelten Männern häufiger als bei den mit Placebo behandelten Männern. Die Häufigkeit dieser Nebenwirkungen sank bei den mit Finasterid behandelten Männern auf 0,6 % im Laufe der folgenden 4 Jahre. Ca. 1 % der Männer in jeder Behandlungsgruppe beendete die Behandlung aufgrund sexueller Nebenwirkungen während der ersten 12 Monate, danach nahm die Häufigkeit ab.Original text: German. Our translation:With frequencies of 3.8% and 2.1% respectively during the first 12 months, sexual side effects were more common in men treated with finasteride than in men treated with placebo. The frequency of these side effects fell to 0.6% in men treated with finasteride over the following 4 years. About 1% of the men in each treatment group stopped treatment because of sexual side effects during the first 12 months; after that, the frequency decreased. 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 revisedSept 2025Checked14 Oct 2026
France	Sexual side effects, as listed4.8. Effets indésirables · Affections psychiatriques · Peu fréquentbaisse de la libidoOriginal text: French. Our translation:decreased libido Sexual side effects, as listed4.8. Effets indésirables · Affections des organes de reproduction et du sein · Peu fréquenttroubles de l'érection, troubles de l'éjaculation (y compris diminution du volume de l'éjaculat)Original text: French. Our translation:erection disorders, ejaculation disorders (including decreased volume of ejaculate) Sexual side effects that continue after stopping4.8. Effets indésirablesDe plus, depuis la mise sur le marché, les effets indésirables suivants ont été rapportés : persistance des troubles de la fonction sexuelle (baisse de la libido, troubles de l'érection et de l'éjaculation) après l'arrêt du traitement par finastéride ; cancer du sein chez l'homme (voir rubrique 4.4 « Mises en garde spéciales et précautions d'emploi »).Original text: French. Our translation:In addition, since marketing, the following adverse effects have been reported: persistence of sexual function disorders (decreased libido, erection and ejaculation disorders) after treatment with finasteride has been stopped; breast cancer in men (see section 4.4 “Special warnings and precautions for use”). The same text also says4.8. Effets indésirablesLa fréquence des effets indésirables rapportés depuis la commercialisation ne peut être déterminée dans la mesure où elle découle de cas de pharmacovigilance spontanés.Original text: French. Our translation:The frequency of the adverse effects reported since marketing cannot be determined, as it derives from spontaneous pharmacovigilance cases. Sexual side effects, as listed4.8. Effets indésirablesLes effets indésirables sexuels ont été plus fréquents chez les hommes traités par le finastéride que chez les hommes recevant le placebo, avec des fréquences respectives de 3,8 % vs 2,1 % pendant les 12 premiers mois. L'incidence de ces effets a diminué à 0,6 % chez les hommes traités par le finastéride au cours des quatre années suivantes. Environ 1 % des hommes (dans chaque groupe) ont arrêté le traitement au cours des 12 premiers mois en raison d'effets indésirables sexuels liés au traitement. Cette incidence a diminué par la suite.Original text: French. Our translation:Sexual adverse effects were more frequent in men treated with finasteride than in men receiving placebo, with frequencies of 3.8% and 2.1% respectively during the first 12 months. The incidence of these effects fell to 0.6% in men treated with finasteride over the following four years. About 1% of men (in each group) stopped treatment during the first 12 months because of treatment-related sexual adverse effects. This incidence decreased thereafter. 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 regulator5 Jan 2026Checked14 Oct 2026
Italy	Sexual side effects, as listed4.8 Effetti indesiderati · Disturbi psichiatrici: · Non comuneDiminuzione della libidoOriginal text: Italian. Our translation:Decreased libido Sexual side effects, as listed4.8 Effetti indesiderati · Patologie dell’apparato riproduttivo e della mammella: · Non comuneDisfunzione erettile, disordini dell’eiaculazione (incluso diminuzione del volume dell’eiaculato)Original text: Italian. Our translation:Erectile dysfunction, ejaculation disorders (including decreased volume of ejaculate) The same text also says4.8 Effetti indesideratiIncidenze presentate quali differenze dal placebo negli studi clinici al 12° mese.Original text: Italian. Our translation:Incidences given as differences from placebo in clinical studies at month 12. Sexual side effects that continue after stopping4.8 Effetti indesideratiInoltre, durante l’uso post-marketing sono stati riportati: disfunzione sessuale persistente (riduzione della libido, disfunzione erettile e disturbi dell’eiaculazione) dopo l’interruzione del trattamento con finasterideOriginal text: Italian. Our translation:In addition, during post-marketing use the following has been reported: persistent sexual dysfunction (reduced libido, erectile dysfunction and ejaculation disorders) after treatment with finasteride was stopped Sexual side effects, as listed4.8 Effetti indesideratiEffetti indesiderati correlati al medicinale inerenti la sfera sessuale sono stati più comuni fra gli uomini trattati con finasteride che fra quelli trattati con placebo con frequenze durante i primi 12 mesi di 3,8 % vs 2,1 %, rispettivamente. L’incidenza di tali effetti è diminuita allo 0,6 % negli uomini trattati con finasteride nel corso dei successivi quattro anni. Circa l’1 % degli uomini in ciascun gruppo di trattamento ha interrotto la terapia a seguito di esperienze avverse della sfera sessuale correlate con il medicinale verificatesi nei primi 12 mesi e l’incidenza è in seguito diminuita.Original text: Italian. Our translation:Drug-related adverse effects affecting the sexual sphere were more common among men treated with finasteride than among those treated with placebo, with frequencies during the first 12 months of 3.8% vs 2.1% respectively. The incidence of these effects fell to 0.6% in men treated with finasteride over the following four years. About 1% of men in each treatment group stopped therapy because of drug-related sexual adverse experiences in the first 12 months, and the incidence decreased thereafter. 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 regulator25 Feb 2026Checked14 Oct 2026
Spain	Sexual side effects, as listed4.8. Reacciones adversas · Trastornos psiquiátricos: · Poco frecuentesDisminución de la libidoOriginal text: Spanish. Our translation:Decreased libido Sexual side effects, as listed4.8. Reacciones adversas · Trastornos del aparato reproductor y de la mama: · Poco frecuentesDisfunción eréctil, trastorno de la eyaculación (incluida disminución del volumen de eyaculación)Original text: Spanish. Our translation:Erectile dysfunction, ejaculation disorder (including decreased volume of ejaculate) The same text also says4.8 Reacciones adversasLas incidencias se presentan en forma de diferencia respecto al placebo en estudios clínicos a los 12 meses.Original text: Spanish. Our translation:Incidences are given as the difference from placebo in clinical studies at 12 months. Sexual side effects that continue after stopping4.8. Reacciones adversasAdemás, durante su uso después de la comercialización se ha notificado: persistencia de la disfunción sexual (disminución de la libido, disfunción eréctil y trastornos de la eyaculación) después de la interrupción del tratamiento con finasteridaOriginal text: Spanish. Our translation:In addition, during use after marketing the following has been reported: persistence of sexual dysfunction (decreased libido, erectile dysfunction and ejaculation disorders) after treatment with finasteride was stopped Sexual side effects, as listed4.8. Reacciones adversasLas reacciones adversas sexuales relacionadas con el medicamento fueron más frecuentes en los varones tratados con finasterida que en los que recibían un placebo, con frecuencias durante los 12 primeros meses del 3,8 y el 2,1% respectivamente. La incidencia de estos efectos disminuyó al 0,6% en varones tratados con finasterida durante los cuatro años siguientes. Aproximadamente el 1% de los varones en cada grupo de tratamiento interrumpió el tratamiento debido a reacciones adversas sexuales relacionadas con el medicamento en los primeros 12 meses, y después la incidencia disminuyó.Original text: Spanish. Our translation:Drug-related sexual adverse reactions were more frequent in men treated with finasteride than in those receiving placebo, with frequencies during the first 12 months of 3.8% and 2.1% respectively. The incidence of these effects fell to 0.6% in men treated with finasteride over the following four years. About 1% of the men in each treatment group stopped treatment because of drug-related sexual adverse reactions in the first 12 months, and the incidence decreased afterwards. 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 revisedNov 2025Checked14 Oct 2026
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):pode sentir menos desejo de manter relações sexuais e/ou dificuldade na obtenção de uma ereção.Original text: Portuguese. Our translation:you may feel less desire to have sexual relations and/or have difficulty getting an erection. 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):pode ter uma redução na quantidade de sêmen liberada durante a relação sexual (isto não parece interferir na função sexual normal).Original text: Portuguese. Our translation:you may have a reduction in the amount of semen released during sexual intercourse (this does not appear to interfere with normal sexual function). The same text also says8. QUAIS OS MALES QUE ESTE MEDICAMENTO PODE ME CAUSAR?Nos estudos clínicos, estes efeitos adversos desapareceram em homens que pararam de tomar finasterida e em muitos homens que continuaram o tratamento.Original text: Portuguese. Our translation:In clinical studies, these adverse effects disappeared in men who stopped taking finasteride and in many men who continued treatment. 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:problemas de ejaculação que continuou após a descontinuação do tratamentoOriginal text: Portuguese. Our translation:problems with ejaculation that continued after treatment was discontinued 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:diminuição do desejo sexual que continuou após a descontinuação do tratamentoOriginal text: Portuguese. Our translation:decreased sexual desire that continued after treatment was discontinued 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:dificuldade de ter ereção que continuou após a descontinuação do tratamentoOriginal text: Portuguese. Our translation:difficulty having an erection that continued after treatment was discontinued 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 approved13 Feb 2025Checked14 Oct 2026
India	Sexual side effects that continue after stoppingUndesirable Effects · Postmarketing Experience · Reproductive System:Sexual dysfunction that continued after discontinuation of treatment, including erectile dysfunction, libido disorders, ejaculation disorders, and orgasm disorders; male infertility and/or poor seminal quality (normalization or improvement of seminal quality has been reported after discontinuation of finasteride); testicular pain. The same text also saysUndesirable Effects · Postmarketing ExperienceThe following adverse reactions have been identified during post-approval use of finasteride. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure: 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 revisedOct 2018Checked14 Oct 2026

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 14 October 2026. 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.

Low-dose finasteride: fewer side effects?

Do lower doses of finasteride cause fewer side effects?

Does half a finasteride tablet lower DHT less?

Does taking finasteride every other day help?

What can I do?

Report it: it helps everyone

What else do people ask?

Sources

Lasting side effects after finasteride?
Make them count.

Read next

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Yellow Card data: look up a medicine's reports

What to say at an NHS sexual health clinic

Finasteride: what the official texts say, country by country

Brand names

What is not known

Code and reporting