Finasteride side effects after years of use

Yes, finasteride side effects can begin after years of use. The UK leaflet warns that sexual problems can last after stopping, a condition known as post-finasteride syndrome, or PFS.

PFS is more than sexual problems. Criteria proposed by doctors and researchers in 2022 also describe problems with thinking, depression and suicidal thoughts, which can happen with or without sexual changes.

Many long-term users feel they’re past the risk. We read the UK leaflet and the regulator’s 2024 review in October 2026 and found no point after which you’re in the clear.

Pablo started finasteride at 21 and later switched to dutasteride, a similar drug. Seven years in, he felt sure he was fine. “Okay, I’m safe with this,” he thought, after years “with apparently no problems”. In the extract below he explains what changed after a 10-day break.

Play video: Pablo on seven years of finasteride and dutasteride (Moral Medicine, extract)

Am I safe if I’ve taken finasteride for years?

Not for certain. In the trials behind the label, sexual side effects were reported less often after the first year. The UK leaflet also says some side effects are temporary with continued treatment.

Later starts have been reported too. The UK medicines regulator, the MHRA, reviewed its Yellow Card reports of sexual and mood side effects. The longest gap was more than 16 years after the person started. Single reports can’t prove the tablets caused it, and the MHRA says no firm conclusions can be drawn from them. Our article on when finasteride side effects start goes through that timing.

Matt says he took finasteride for three years “without any issues”. Then one day he woke with “a strange dead sensation” in his genitals.

What happened to Pablo after seven years?

Pablo took finasteride 1 mg for about three and a half years, then dutasteride for about as long. Apart from some testicular pain at the start, which eased, he noticed no problems. The trouble began after that 10-day gap.

When he took a tablet again, he says, “I feel it immediately that something was wrong.” His testicles hurt, and his sex drive and energy dropped. He took one more, then stopped for good. Those symptoms faded within about five days.

About a month later, his sex drive dropped and erections became difficult. A couple of weeks after that, he couldn’t sleep. When he was interviewed, about six months after stopping, he had severe memory problems and couldn’t focus. The cognitive and sexual symptoms were the worst, he says.

The 2022 diagnostic criteria for PFS say a lasting problem may only appear when the drug is stopped. Our article on stopping finasteride has more on that.

Could problems I’ve had for years be finasteride?

They could. Tim only made the link after many years. He took finasteride 5 mg a day for a prostate problem from 2008 to 2025. His sex drive and erections went soon after he started, he says. He was told he might need it for the rest of his life.

He connected it only when a warning card turned up in his tablet box. The MHRA announced that card for every pack in 2024. He stopped taking it. In the extract he explains how that card changed what he understood. When he was interviewed nearly a year later, nothing had changed.

Play video: Tim on 17 years of finasteride 5 mg (Moral Medicine, extract)

The Proscar leaflet for the 5 mg dose (August 2024) lists an inability to have an erection “which may continue after stopping the medication”. More on that dose is in Finasteride 5 mg (Proscar) side effects.

What can I do?

Finasteride helps many men keep their hair, and many take it for years without problems. If you have side effects, that’s a decision for you and your prescriber.

If your mood drops or you have suicidal thoughts, the Propecia leaflet says to stop taking it and contact your doctor as soon as possible. The Proscar leaflet, for 5 mg, says to contact your doctor as soon as possible. The Samaritans are on 116 123, free, at any hour.

Write down your dates: “Finasteride 1 mg from May 2018. Lower sex drive since about March 2026. Still taking it.” Many people say it took time to be taken seriously. Bring the leaflet line. Our guide to which doctor to see for PFS can help.

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.
• 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?

Do side effects go away if I stop after years? The Proscar leaflet says sexual side effects usually resolve after stopping. It also lists some that may continue. For some people it has lasted years after stopping. Nobody knows yet who will be affected, or whether it will ease. Tim’s hadn’t changed after nearly a year.

Are there other side effects to watch for on long-term finasteride? The leaflets ask you to tell your doctor promptly about any changes in your breast tissue, “such as lumps, pain, enlargement or nipple discharge”. They say these may be signs of a serious condition, such as breast cancer. Our article on finasteride and breast changes explains more.

Does taking finasteride for longer raise the risk? One study suggests it may. In the medical records of young men on the hair-loss dose, about 12 in 1,000 who’d taken it for more than about 200 days had lasting erection problems, against about 2 in 1,000 with shorter use. It can’t say whether ten years is riskier than three. See PFS after a few pills.

Pablo thought years without problems meant he was safe. If something changes for you, after one year or ten, note the date and report it. PFS is easier to recognise when it’s written down.

Sources

1. Propecia 1 mg film-coated tablets, patient information leaflet, electronic medicines compendium (emc), last revised May 2026. Section 4, frequency unknown: “persistent difficulty having an erection after discontinuation of treatment”, “persistent decrease in sex drive after discontinuation of treatment” and “persistent problems with ejaculation after discontinuation of treatment”. Section 4 also says: “Some of the side effects are temporary with continued treatment or disappeared when treatment is stopped”. In section 2, on mood alterations and depression: “If you experience any of these symptoms stop taking Propecia and contact your doctor for further medical advice as soon as possible”. Section 4 adds: “You should promptly report to your doctor any changes in your breast tissue such as lumps, pain, enlargement or nipple discharge as these may be signs of a serious condition, such as breast cancer.”
2. Propecia 1 mg, summary of product characteristics, emc. Section 4.8: sexual side effects 3.8% on finasteride against 2.1% on placebo in the first 12 months, falling to 0.6% on finasteride over the following four years.
3. Proscar 5 mg film-coated tablets, patient information leaflet, emc, last revised August 2024. Section 4: impotence, lower sex drive and ejaculation problems “may disappear after a while if you continue taking Proscar. If not, they usually resolve after stopping Proscar”. It also lists “An inability to have an erection which may continue after stopping the medication”, “Decrease in sex drive that may continue after stopping the medication” and problems with ejaculation that may continue. The same breast tissue line as the Propecia leaflet. Section 2: for mood changes, “contact your doctor for further medical advice as soon as possible”.
4. MHRA, Safety review of finasteride: public assessment report, April 2024. Section 5.2: Yellow Card reports up to 5 January 2023 of sexual dysfunction (375) or depressed mood and suicidal behaviour (231), both doses. Time to onset was documented in 252 reports (42%): average 330 days, range 1 to 5,923 days (about 16.2 years), across the sexual and mood reports together. The MHRA says no firm conclusions can be drawn from spontaneous reports. Annex 1: the patient card wording for 1 mg and 5 mg.
5. 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, April 2024: a patient card to be introduced in every pack.
6. 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. “In some cases, an enduring sexual dysfunction may only appear when the drug is stopped, or a mild dysfunction on treatment may worsen on stopping.” Section 5: for finasteride, cognitive impairment, depression and suicidality can occur with or without sexual difficulties.
7. Kiguradze T, Temps WH, Yarnold PR and colleagues. Persistent erectile dysfunction in men exposed to the 5α-reductase inhibitors, finasteride, or dutasteride. PeerJ 2017;5:e3020. Northwestern Medicine electronic records of men aged 16 to 42 on finasteride 1.25 mg a day or less. Erectile dysfunction lasting at least 90 days after stopping in 30 of 2,587 with more than 205 days of use (1.16%) and 4 of 1,697 with 205 days or fewer (0.24%), from table 3C. Single-group design; association, not proof of cause.
8. Moral Medicine interviews on YouTube, from the automatic captions. Pablo, 22 September 2025 (23 minutes), embedded as an extract from 3:32 to 6:16. Times in his interview: “Okay, I’m safe with this” and “apparently no problems”, 0:05 to 0:23, repeated at 18:19. Started at 21, 1:47. Finasteride 1 mg for about three and a half years, “with no apparently issues apart from some testicular pain at the beginning”, which went with time, 3:38 to 3:51. Dutasteride for about three and a half more, seven in all, 4:19. Ten days without while travelling, 4:42. “I feel it immediately that something was wrong”, 4:58. Symptoms resolved after about five days, 5:45. Low libido and erectile dysfunction about a month after stopping, 6:05 to 6:22. Insomnia, 6:46. Six months since stopping, 7:30. Memory and focus, 8:05. The cognitive and sexual symptoms the worst, 10:40. Tim, 23 March 2026 (15 minutes), embedded as an extract from 3:09 to 5:22. Started in 2008, 2:32. Told he might need it for life, 2:55. No libido and no erections, 3:17. From 2008 to 2025 at 5 mg a day, 4:07. Connected it after the warning card in his box, 4:17. Stopped, 4:54. Nothing changed, 5:02. Off it nearly a year, 5:14. The interviewer sums up at 13:02 that his side effects began within months of starting.
9. Matt’s interview with Moral Medicine, 6 April 2026: “finasteride for 3 years without any issues”, then waking with “a strange dead sensation” in his genitals.
10. Their stories on our site: Pablo, Tim and Matt.
11. PubMed searches on 21 October 2026 for finasteride with late, delayed or time to onset and sexual or erectile side effects found no study that counts how often side effects first begin after years of use. The one relevant hit (FAERS, PLoS One 2025) analyses spontaneous reports, which cannot give a rate.