PAS, PFS and PSSD: what they share

Post-Accutane syndrome (PAS), post-finasteride syndrome (PFS) and post-SSRI sexual dysfunction (PSSD) follow three different kinds of medicine. They share a core of symptoms that can last after stopping. The sexual core is less feeling in the genitals and in orgasm, less desire and erection problems.

They are more than sexual problems, even though the names suggest it. A 2022 expert paper lists emotional numbing, problems with thinking and changes in other senses for PSSD. For PFS and PAS it lists problems with thinking, depression and suicidal thoughts, which can happen without any sexual problem.

That paper set criteria for all three side by side. It shows where they overlap and where they part, which helps when a doctor has heard of only one.

Elliot took a short course of Accutane at 17. Watch this 90-second extract to hear how far beyond sex the effects can reach: Moral Medicine asked him what he lives with day to day.

Play video: Elliot on what he lives with after Accutane (extract)

He lists dry, thin skin, aching shoulders and a gut where “nothing really sits”. Emotionally, he says, it’s “flatline emotions”, apart from “fear and panic”.

The man interviewing him has PFS, from a different medicine taken for a different reason. Earlier in the same conversation he says that with PFS he’s blunted: “I don’t feel those emotions at all.”

What do PAS, PFS and PSSD have in common?

The sexual symptoms, mostly. The 2022 criteria paper says all three “commonly include decreased genital and orgasmic sensation, decreased sexual desire and erectile dysfunction”.

The shared rules: the problem has lasted three months or more after stopping, wasn’t there before the medicine, and no other illness, medicine or drug use explains it. The paper sets no upper limit, and it can first appear after stopping. Side effects after stopping covers the timing and what UK leaflets warn.

Reports match, too. A 2018 study looked at 300 reports of lasting sexual problems sent to RxISK, a drug safety website. Erection problems, low desire and genital numbness were the three commonest complaints from men after antidepressants, finasteride-type medicines and isotretinoin alike.

These people chose to report to the website and there was no comparison group, so the counts can’t show how often this happens or prove cause.

How are PAS, PFS and PSSD different?

They differ in one sexual symptom and in what comes with it. Under the heading “Necessary”, the PSSD criteria require a lasting change in genital feeling. For PFS and PRSD, the necessary criterion is a lasting sexual problem of any kind. Less genital and orgasm feeling is among their additional criteria.

What the 2022 criteria list

1

PSSD, after a serotonin reuptake inhibitor such as an SSRI or SNRI

Necessary: a lasting change in genital feeling. Non-sexual symptoms may include: emotional numbing, feeling detached from yourself, sensory problems with skin, smell, taste or vision, and problems with cognition.

2

PFS, after a 5-alpha-reductase inhibitor such as finasteride

Necessary: a lasting sexual problem. Effects that can come with or without it: problems with cognition, depression, suicidal thoughts.

3

PRSD, after isotretinoin

Necessary: a lasting sexual problem. The additional criteria include loss of vaginal lubrication in women. Effects that can come with or without it: as for PFS, plus skin, joint and bowel changes.

The criteria list emotional numbing only for PSSD, yet Elliot and his PFS interviewer both describe something like it. In the 2018 reports, men described emotional blunting after all three kinds of medicine. More on emotional numbness and medicines and after Accutane.

Some differences turned up only in the 2018 reports. Premature ejaculation came only after antidepressants. Shrinkage of the penis or testicles was reported more often after finasteride-type medicines.

Max took sertraline for about a month. Here he describes the emotional side of PSSD in a way a list can’t.

Play video: Max on losing his emotions after sertraline (extract)

After stopping, he says, he had “no emotions at all”, and lost the pleasure he used to get from music, friends and food. He felt like “some sort of a shell”.

Why would three medicines cause similar symptoms?

Nobody knows yet. The criteria paper notes that isotretinoin blocks serotonin reuptake, as an SSRI does, and blocks 5-alpha-reductase, as finasteride does. It isn’t clear, the paper says, whether the problem comes from either action.

A 2023 review from Milan proposes that PFS and PSSD may share mechanisms, such as brain steroids, serotonin and gut bacteria. Our summary of that review has more.

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 and isotretinoin, follow what the leaflet says.

If a problem hasn’t lifted since you stopped, tell your GP the medicine and dates: “Isotretinoin 40 mg from March 2019, last capsule September 2019.” Say what changed, in your own words, such as “touch feels numb”. 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.
• Use the right words. If symptoms continued after stopping, write Post-SSRI sexual dysfunction (MedDRA 10086208) for an SSRI or SNRI, or Post 5-alpha-reductase inhibitor syndrome (MedDRA 10082430) for finasteride. For isotretinoin there’s no term yet, so say the symptoms continued after stopping.

Our reporting guide walks you through it

What else do people ask?

Do they last as long as each other? Nobody can say. The criteria set no upper limit for any of the three. In the 2018 reports, five people said it had been over 20 years since they stopped isotretinoin or fluoxetine.

Can you have PFS and PSSD at once? The 2022 criteria don’t allow for it. They say PFS or PRSD shouldn’t be diagnosed in someone who has taken one of the other medicines before. Noah came off citalopram while taking pygeum, a supplement he describes as a 5-alpha-reductase inhibitor. He doesn’t know which symptoms come from which.

What does each one feel like? People describe them in their own words in our pages on PSSD, PFS and PAS.

Elliot and the man interviewing him took different medicines for different reasons, and both describe their emotions going flat. If a medicine changed something for you that hasn’t come back, report it and say when you stopped.

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. Read in full on 21 October 2026 (NCBI BioC full text). Each condition’s criteria are under the paper’s own headings “Necessary”, “Additional” and “There should be”. An expert consensus built from two case series (Hogan 2014, Healy 2018) of reports to RxISK.org; the authors include people linked to RxISK. Abstract: “Features of PSSD, PFS and PRSD commonly include decreased genital and orgasmic sensation, decreased sexual desire and erectile dysfunction. Ancillary non-sexual symptoms vary depending on the specific condition”. PSSD, necessary criterion 2: “An enduring change in somatic (tactile) or erogenous (sexual) genital sensation after treatment stops”; ancillary non-sexual symptoms: emotional numbing, depersonalisation, other sensory problems involving skin, smell, taste or vision, cognitive impairment. PFS and PRSD necessary criterion 2: “Enduring sexual dysfunction after stopping treatment”; PRSD additional criterion 4 includes “loss of vaginal lubrication (females)”. Effects that can occur with or without sexual difficulties: for finasteride, cognitive impairment, depression, suicidality; for isotretinoin, cognitive impairment, skin, joint and bowel changes, depression, suicidality. All three: problem present 3 months or more after stopping, and no matching pre-drug problem. Also no current condition, medication or substance misuse that could account for it. PFS and PRSD add “No other prior medication that could account for the symptoms” and “no prior use” of the other two groups. Isotretinoin “has both serotonin reuptake inhibiting and 5 alpha-reductase inhibiting properties”; the paper says it is not clear whether the problem comes from either action. PAS “is in widespread use and often refers to what is termed PRSD here but equally often appears to include suicidality and other cognitive effects without sexual difficulties”. No upper limit on duration; dysfunction may first appear or worsen on stopping. “The incidence of these conditions is unknown.”
2. Healy D, Le Noury J, Mangin D. Enduring sexual dysfunction after treatment with antidepressants, 5α-reductase inhibitors and isotretinoin: 300 cases. Int J Risk Saf Med 2018;29(3-4):125-134. Read in full on 21 October 2026. 300 reports to RxISK.org, a drug safety website set up by the authors and colleagues, from 37 countries. Men: erectile dysfunction, loss of libido and genital anaesthesia were the three commonest symptoms in each drug group (Table 3a). Emotional blunting reported by men in all three groups (Table 3a). Pleasureless or weak orgasm “is also common to the three treatment groups”. Premature ejaculation and PGAD reported only after serotonin reuptake inhibitors. Reduced penis size and testicular atrophy more often after 5α-reductase inhibitors (25 men). Cognitive problems including brain fog and memory impairment “were worse on finasteride”. Five people reported over 20 years since stopping isotretinoin (4) or fluoxetine (1). Self-selected reports with no comparison group, so the counts cannot give a rate or show cause.
3. Giatti S, Diviccaro S, Cioffi L, Melcangi RC. Post-finasteride syndrome and post-SSRI sexual dysfunction: two clinical conditions apparently distant, but very close. Front Neuroendocrinol 2024;72:101114 (online 21 November 2023). University of Milan. Abstract read: common mechanisms proposed, with roles for neuroactive steroids, serotonin and catecholamines, and gut microbiota; “more work is still needed”.
4. Moral Medicine, He Took Accutane at 17. His Life Never Returned to Normal., interview with Elliot, 28 January 2025. Embedded here as an extract from 1:16:31 to 1:18:00. From the YouTube auto-captions: “nothing really sits in my um gut very easily” (1:17:27), “I won’t go into it, but I know I know the ways this affects me” (1:16:58 to 1:17:00; the effect is not named), “flatline emotions apart from Yeah. fear and panic” (1:17:45 to 1:17:48; “Yeah” is the interviewer). The interviewer, who has PFS: “with PFS, you know, in particular, I don’t I I’m blunted at this point. I don’t feel those emotions at all” (1:07:28 to 1:07:34). His story on our site: Elliot’s story: Accutane at 17.
5. Moral Medicine, interview with Max, 11 February 2026. Embedded here as an extract from 1:46 to 3:27. From the YouTube auto-captions: “no emotions at all” (2:08), the pleasure from music, hanging out with friends and food (2:27 to 2:55), “some sort of a shell” (3:15). Sertraline in 2018 for about a month. His story on our site: Max’s story: 1 month on sertraline.
6. Noah, How SSRIs and 5AR inhibitors devastated my life, his own account on our site. Tapered off citalopram while taking pygeum, “a 5-alpha-reductase inhibiting supplement”; “I don’t know which symptoms are from PFS and which are from SSRI withdrawal”.