PFS and PSSD data: why your report counts

Nobody has counted how many people live with post-finasteride syndrome (PFS) or post-SSRI sexual dysfunction (PSSD), conditions that can last after stopping the medicine. Your report and your registry entry are how that gap gets filled.

It matters because counts change things. In the UK, patient reports and patient voices have already helped change the warnings on finasteride and on antidepressants.

So how many people are affected, and what does your report change?

How many people have PFS or PSSD?

Nobody knows. The 2022 criteria paper says it plainly: “The incidence of these conditions is unknown.”

The official leaflets agree on what can happen, without a number. The UK leaflet for Cipralex (escitalopram) says sexual symptoms have, in some cases, “continued after stopping treatment”. The Propecia leaflet lists “persistent difficulty having an erection after discontinuation of treatment”, with the frequency marked as unknown.

Unknown is not the same as rare. Nobody has run the study that would tell us. Until then, the best counts are the ones patients make themselves: reports to regulators and entries in registries.

PFS and PSSD aren’t only about sex, even though the names point that way. The 2022 criteria put a lasting change in genital sensation, often numbness, at the core of PSSD. They also describe emotional numbing, cognitive problems and changes in other senses.

For PFS, the same paper says cognitive problems, depression and suicidal thoughts “can occur independently of any sexual difficulties”. So a count that only asks about erections misses people.

If you’re struggling or having thoughts of suicide, you can call Samaritans free on 116 123, day or night.

Do side effect reports actually change anything?

Yes, and the UK shows how. In 2024 the medicines regulator, the MHRA, looked again at finasteride after “concerns from patients regarding a lack of awareness of these side effects”.

It had received 426 Yellow Card reports of sexual problems with finasteride. In almost half, the outcome was recorded as “not recovered” or “not resolved”. The MHRA then introduced a patient alert card for men taking finasteride.

In October 2026 it announced new safety measures for antidepressants, after a review that heard directly from patients’ families. The term “Post SSRI Sexual Dysfunction” will be added to some antidepressant leaflets.

One report can’t prove cause. Many of them show a regulator a pattern worth checking.

What is the SIDEfxHUB Registry?

It’s our free registry for people affected by PFS, PSSD or post-Accutane syndrome (PAS). The sign-up page says it takes a couple of minutes, and that your data is never shared without your consent. You can use a pseudonym.

A registry does something a single report can’t. It shows how many people there are, in one place, over time. That helps us make the case to doctors, regulators and funders.

It also helps research. When a team needs people for a study, a registry can put them in touch with patients who’ve said they’re willing. Finding participants is often one of the slowest parts of a study.

We’re also building a patient data platform where people can track their symptoms over time. It’s still in development.

Watch: why doctors need to hear about PSSD

Professor Joanna Moncrieff, a psychiatrist at UCL, talks about PSSD and how aware doctors are of it. It’s background on why the evidence gap matters, not a source for the numbers above.

Play video: Professor Joanna Moncrieff discusses Post-SSRI Sexual Dysfunction (PSSD)

What can I do?

These medicines help many people. If you have side effects, that’s a decision for you and your prescriber. Don’t stop an antidepressant suddenly. For finasteride, follow the leaflet: it says to stop and see your doctor if your mood changes.

Two things make your experience count. Join the registry, and report it to the regulator. Write down your medicine first, for example: “Finasteride 1 mg from June 2021, last tablet May 2023.”

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) for finasteride or dutasteride, or Post-SSRI sexual dysfunction (MedDRA 10086208) for an antidepressant.

Our reporting guide walks you through it

What else do people ask?

Is my data safe in the registry? The sign-up page says your data is never shared without your consent. You can join under a pseudonym. Read the privacy notice on the sign-up page before you join, and ask us if anything is unclear.

Should I report even if I stopped years ago? Yes. A report is useful whenever you make it, and you don’t need a doctor to agree. Our guide to reporting a side effect years later shows how.

Does joining the registry count as a report to the regulator? No. They are separate. The registry helps us show how many people are affected; a Yellow Card or MedWatch report goes into the regulator’s own safety data. Doing both counts twice.

Every entry is one more person who can’t be left out of the count. Join the registry, then read more on our PFS and PSSD pages.

Sources

1. 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 developed through expert agreement. Section 3: genital sensation change at the core of PSSD, with emotional numbing, cognitive impairment and other sensory problems among ancillary symptoms. Section 5: in PFS, cognitive impairment, depression and suicidality “can occur independently of any sexual difficulties”; “The incidence of these conditions is unknown.”
2. 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 up to 5 April 2024, for finasteride 1 mg and 5 mg; spontaneous reports, with no count of how many people took the medicine. UK.
3. MHRA. Antidepressants: new safety measures for all patients. Drug Safety Update, 15 October 2026. Review by a Commission on Human Medicines expert working group, May 2024 to July 2025. UK.
4. Lundbeck Limited. Cipralex (escitalopram) patient information leaflet, electronic Medicines Compendium. Section 2: “In some cases, these symptoms have continued after stopping treatment.” UK.
5. Organon. Propecia (finasteride 1 mg) patient information leaflet, electronic Medicines Compendium. Section 4, frequency unknown. UK.
6. SIDEfxHUB. SIDEfxHUB Registry sign-up page.
7. GOV.UK. Report a problem with a medicine or medical device.
8. PSSD Network, Professor Joanna Moncrieff discusses Post-SSRI Sexual Dysfunction, June 2026. Used for general context.

Sources checked on 22 October 2026. AI-assisted writing and review, not clinical review.