Firsthand experiences of finasteride — Volume I: Rapid onset

Following are online reports from men who experienced adverse effects, some of which were severe, after taking a single dose or a small number of doses of finasteride. Bold text is in original and has not been added. None of these posts is from a support forum for post-finasteride syndrome. These are from hair loss forums or general online forums. Many come from the subreddit r/tressless where reports of finasteride’s adverse effects are often met with downvotes, skepticism and personal attacks.

Finasteride side effects are ONE pill

So I am a 20 year old male who has had a [f***ed] hairline for quite a while now so thought I would give finasteride a try and was planning on taking 1mg every other day.

I took the first pill Saturday and woke up Sunday morning with no morning wood like I usually have and could only get to like 70 percent hardness that day. It is now Monday morning and I could barely sleep last night and my [penis] is so shrivelled and small it is actually quite funny 🤣 obviously I am not taking any more of this stuff as I am not reacting well to it but could anyone give me and idea to when I should be back to normal? Thanks

Meant to be after in title instead of are*

Post on r/tressless, 8 Mar 2021

Post Finasteride Syndrome – Single 1mg pill, 16 months and counting

Hey guys,

I’m a 25 year old male, and I took a single 1mg pill of generic Finasteride back on October 23rd 2018. By the next morning, my perception and vision was completely altered, like I was separate from reality. It worsened into constant, horrible brain fog, a “dead space” feeling inside my head, loss of deep sleep, and a physical disconnect from my body. I got many imaging and lab tests done, and it finally showed that I had low bioavailable and free testosterone and high cortisol. I tried Clomid but it hasn’t helped at all.

My entire skin complexion changed and my skin is soft, gray, and rubbery. I have substantial muscle weakness all around and I’m gaining this weird hormonal fat in my thighs. My thighs have tripled in size almost. I continue to have brain fog just as bad as day 1 and I am just going downhill. I was a very avid weightlifter and fitness fanatic before all of this and this whole experience has been heartbreaking. I am currently finishing the first year of Physical Therapy (DPT) school, but I’m taking a 12-month medical leave in May to go stay with my mom. I’ll be implementing fasting, herbs, and other natural remedies in hopes for improvement. I’ve been completely independent since 18 years old and this has ruined my life. It blows my mind every day that a single 1mg pill has done this. I’m getting more bloodwork done soon to check for thyroid and sex hormones again, as the Clomid did not help. It’s literally like my metabolism and endocrine system have shut off. I don’t have any connection to my muscles and my body is just swelling. All of my skin, muscles, and hair is completely different.

Post on r/tressless, 22 Feb 2020

I took a dose of Fin and this is what happened

This will be my last post ever on this board. I posted about a week ago right after I took the first pill, I was freaked out and didn’t know what was going on. That post was met with nothing but vitriol, everyone ganged up on me and called me everything under the sun. I understand why few people post here nowadays.

However, I think that there’s quite a few people on this board right now in the same spot I was in a week ago: wanting to go ahead and give Fin a try. Trying to figure out if it’s worth it or not. I’m here to tell you what happened to me these past 5 days after I took that first dose.


Some backstory about my general health: Mid 20’s, no illnesses, BMI in order, going to the gym rather frequently, strong libido, eating clean, supplementing with Vit C/D & Fish Oil every day.

I woke up last Wednesday and decided that today was the day. I decided that the research is conclusive and this drug is safe to take. I had a doctor’s prescription, got a box from my pharmacy which had the seal on and everything. Took out a pill and split it in 4s. I didn’t cut it correctly tho and ended up with some uneven pills..and I took the smallest of the bunch. Must’ve been about .2mg of the thing.

5 minutes later I started feeling my penis kind of shriveling up and going limp. I knew I was panicking but the panic attack was great. My arms felt heavy and things seemed numb to the touch. Now..I’m not going to claim that these are effects of the Finasteride, this was probably my anxiety. But as I went out to get some fresh air I noticed a dull pain right in my lower abdomen. I felt like my legs were sore and I couldn’t feel my dick. It was extremely scary. As I walked behind a pretty girl I realized that although my brain found her attractive it was like that information wasn’t getting ‘where it matters’. That of course, freaked me out some more. Although this was happening, I managed to calm down and just wait it out. It was temporary, I thought.

The dull pain remained and a weird numb feeling was radiating from around my testicles. Because of that I thought that I surely couldn’t get an erection to save my own life. To my surprise..I was able to get one rather easily. So I thought everything is ok. It’s now been 5 days since I took that dose but I am left with only symptom: around 40-50% loss of sensitivity in my penis (especially around the base), about an inch or so lost in total length at full erection and a numb, pulsing feeling that seems to be coming from my prostate.

I am going to get some blood tests to determine if perhaps the pill has made me androgen deficient for some reason. However, I strongly don’t think that’s the case, seems a bit more neurological since I wake up with morning wood every day, I can attain a full erection and I ejaculate – although my semen also seems more watery than usual. I have doubts about my fertility right now.

These symptoms are definitely not in my head, they’re unfortunately as real as it gets and I strongly fear that it’s something I’m going to have to live with for the rest of my life. I now understand that the decision I took was out of vanity and there’s far worse things in life than losing your hair. The dose of fin doesn’t guarantee you’ll keep it anyway.

I know what the studies say cause I read them all. Learn from my mistake and from others and just don’t do it. The side effects are real, potentially permanent (as it says right on the box) and not worth it. I plan on updating this post if one day I wake up feeling like before that pill.

Post on r/tressless, 2 Mar 2020

Comment to the post immediately above:

I am seriously here and I am [****ing] terrified man. I only took two doses of 0.25mg and just like this guy five days later I lost sensitivity. I really really really really hope I go back to normal. I’m only 30.

Comment on r/tressless, 17 Jun 2020

I am a medical student who has made one of the worst decisions of his life by taking finasteride.

I made a massive mistake in trying finasteride for the second time. I’m currently in my mid 20s and first tried finasteride soon after i turned 18. I was on it for under two weeks and had side effects such as ball ache and erectile dysfunction. Thankfully these side effects went away within a month after quitting. I had reasoned to myself that what i had experienced was in my head being a silly 18 year old at the time, and made the stupid spare of the moment decision to give it another whirl shy of a decade later after a bad day of feeling insecure about my hair (I got a new prescription a couple of years earlier but decided not to not take it, until recently).

I had a single pill this time, i forgot to take more pills the following days and had a think about taking it again. I had already had a shaved head for years and was more or less happy with the way i looked. I think a bad day drove me to try finasteride again, I dunno, anyway i decided [**ck] it’s not worth the hassle or the risk, i laughed at myself for trying it again.

All was well and good for several days until strangely i almost completely stopped sleeping (1-2 hours a night) for about 2 weeks. This improved to 3-4 in the following weeks and between 4-6 hours that i’m sleeping now (for the last 2 months). Mind you i used to sleep a consistent 8-9 hours a night and my sleep never feels refreshing now it is very strange to describe. I now have to rely on sleeping medications every night for sleep for the last 3 months or so.

I have never had any problems maintaining an erection outside the times that i have tried fin, could seemingly get a rock hard erection and ejaculate many many times a day if i felt like it. Over the last 3.5 months since taking finasteride my erection quality has gradually degraded to the point that i cannot maintain an erection anymore. I had always had a high libido this has now decreased to almost nothing over the last few months. I have other possible sexual side effects but won’t go into depth for the sake of brevity.

Finally i have always been a very lean individual with significant muscle mass, i have not deviated from my weight since about 20 years old, over the last 3 months i have seen a decrease in muscle mass and an increase in fat, i’ve now put on approximately 12 pounds of fat despite exercising even more than i used to and no change in diet. My weight has not stabilised and i will likely put on more.

I have seen several doctors about this who have known me for years. After showing them some of the recent studies on finasteride in conjunction with them knowing my history they all agree that this is likely an effect of finasteride. The fact is that PFS is unequivocally a real condition, studies from the last 5-8 years strongly strongly support it’s existence. There is no doubt that PFS is uncommon but some published studies estimate that persistent sexual dysfunction could lay between 1-2% of those who try finasteride. Recent animal studies have confirmed that finasteride induces depressive behaviour in mice, lowers key neurosteroids (important for neuro-protection, neuro-plasticity, mood regulation and sleep) and induces penile shrinkage. On top of this it now appears obvious that Merk has not been completely transparent or honest about the real incidence of side effects. Meta analyses have confirmed that no clinical trials of finasteride have adequately assessed its safety or how long sides persist after cessation. How can anyone be comfortable taking a cosmetic drug long term given these facts? France has already acknowledged the existence of PFS and other countries will soon follow, it is nothing less than a crime that legislators have not put out more warnings against this drug given recent scientific studies.

Please guys hair really isn’t that important people have lost their hair from the beginning of time and managed to live long fulfilling lives. Your health is far more important. There are no biomarkers or good guesses that can predict whether you may develop PFS, you are essentially playing Russian roulette over a cosmetic issue.

I myself realised how trivial hair really was years ago but somehow still fell into this trap again, don’t be like me. I am considering dropping out of medical school because of my current situation. The lack of sleep and the toll of losing my sexuality is really doing a number on me. I hope to one day get back to where i was but it is not looking good. Be safe out there folks.

Post from r/tressless, 6 Feb 2020

Finasteride side effects after stopping


Could someone help me? I’m seriously at a loss right now, and I have no clue what to do.

I got a prescription for finasteride, which I had to stop using within one month because of side effects.

During use:

• 3 days in, I noticed my flaccid size was much smaller than usual. Other posts here reported the same thing, with it going away after some time, though, so I stuck with it, hoping it’d go away.
• 1 week later, my erections were around a third smaller than usual, and orgasms were less pleasurable. My erections would keep taking on this strange hourglass shape.
• 3 weeks in, my libido dropped down to 30%, and I noticed I didn’t have any sexual tension while I was around girls, so I decided I’d stop if this didn’t go away within the next week.

Well, I stopped, but things just got even worse.

After stopping:

• A few days after, I woke up with a really bad groin ache, as well as a headache which bogged me down a bit the entire week. My genitals have been numbed quite a bit. No brain to genital connection, at all.

I went to an urgent care doctor, who said these might just be some withdrawal symptoms, they occur even while using it, and that they should go away on their own if I gave it some time.

I didn’t feel comfortable taking any more medications (other than some OTC pain killers), so I didn’t push him to look into any further– finasteride has still suppressed my DHT for the rest of the week (see serum DHT graph), right?

Fast forward to today, and I literally feel like I’ve been castrated.

Right now, I have:

• Brain fog
• Anhedonia
• Chest soreness
• Genitals which seem to keep on shrinking
• Absolutely no extra pleasure from ejaculating, loads are a quarter of what they used to be
• And just a week ago, I developed insomnia (I sleep 5 hours max now).

Most of it does seem to be psychological, but if this pill caused all of these physical changes to me, who knows what the hell it’s done inside of my brain.

TL;DR: Is there anyone who felt even worse after stopping finasteride, and had their issues resolve after some time? What should I do if these issues continue to persist, or what should I ask an endocrinologist to look for (how do I know if they’re looking for the right things, e.g.?).

Sorry, I know this was a long post, but this has been an incredibly frustrating experience overall. Thank you!

Post on r/tressless, 15 May 2019

Comment to post immediately above:

HOW DID I MISS ALL OF THIS GOD FKIN DAMMIT I’m in the same situation as you are since yesterday. My dick reacts absolutely 0 to anything. No porn no touching nothing, its just a [f***ing] limb noodle. I dont even give a shit about all that awful rest, but I need my dick..Didn’t sleep yesterday all night and couldn’t sleep today trying for 2-3 hours. Already afraid of the night to come.. slight right ballache and breast tenderness. Head feels like exploding, heart is half of the day in fkin fight or flight mode. Im absolutely devastated and had my first mental breakdown in my life. I don’t know what to do and am at loss.

From comment to post on r/tressless

Stopped taking finasteride after 1 week

I’ve slowly been receding since my early 20s (im 30 now) and have been on minoxidil on and off for a few years. After reading everyone’s testimonies and the chance of any side effects I finally decided to take the plunge and start using finasteride.

I got my prescription for 1mg of generic fin and as soon as I took the first pill I had a weird feeling in my groin area. I ignored this and as the days passed the symptoms started to get worse, ball pain, no libido, and loss of random erections and morning wood. My penis felt like an artificial limb that was just hanging there its kind of hard to describe. I started thinking about how it wouldn’t be so bad losing hair as long as my dick worked. Its not until you actually get in the medication you start thinking about what it can actually do to your hormones.

So I stopped and slowly but surely the symptoms have gone away. Idk if I’ll ever get back on it or just keep using min with some other alternative. I wish it would have worked for me like so many others have posted, but im probably one of the unlucky few who are more susceptible to the symptoms. While I was taking it my hair did feel thicker and absolutely no shed in the shower. But I wouldnt trade perfect hair for loss of sexual function.


Post on r/tressless, 30 Oct 2018

Immediate sexual side effects of Finasteride – will it go away?

Hello everyone, I’m new here.

I’m 23 and have started taking 1mg generic finasteride (Sandoz) for the past 3 days. I’m already feeling a dramatic change in libido and being able to have and maintain an erection. I also feel occasional soreness in my testicles. 

Now I just wanted to ask if any of you have similar experiences? And if these effects will go away if I stay on the drug?


Post on baldtruthtalk, 11 Mar 2011

Finasteride and sexual side effects

Hi! I would really like to hear expriences when using finasteride during the first six months, because when I started it, my doctor didn’t really talk about any side effects other than reduced sperm count, so that having children would be more difficult, if I were to have them.

Anyway, I started finasteride last summer and noticed almost immediately (within a week) the sexual side effects. These included; more watery ejaculations and numbness during intercourse. I just thought then that these happened because of the drug and (maybe?) they would go away. I could still have an erection and sex, but as I continued taking the drug, I couldn’t have erection unless I really got into it and try to excite myself. And even sometimes during sex, my erection just would face [fade] away and come back, or not be as strong as it could have been. Although I thought every time that the problem where the drug. So could it have been just a placebo because I’ve read about the side effects when taking it?

One day I just happened to read an article regarding bodybuilding, and DHT because I’ve been going to the gym for a five years now and then I realized how I didn’t no longer had morning erections or erections during the day, which both occurred many times before in my life. All I could think was that this was all due to finasteride and I stopped taking it. Then after I stopped taking the drug, the morning erections came back, and I could have an erection when thinking about sex during the day. My girlfriend noticed how I could keep an erection all the time during sex when I stopped the drug and I could see myself much more horny than during the drug and now that I think of, my erections are much stronger that during the drug.

I took the drug for about four months, and now, after four months without it, I can see how my hairline really is going back to where it was before the drug, and it’s rapidly receding. Finasteride really DID stop the balding and I could easily see how my hair got stronger and even saw regrowth on the temples. It really did do the trick, unfortunately with the side effects..

So my question is, has anyone who has taken the drug exprienced the same effects, within four months? Did they go away eventually? As I see my hairline receding again, I think about taking the drug again but I can not live with these side effects for the rest of my life.

Post on r/tressless, 15 Feb 2016

Sudden erectile dysfunction

Just like magic poof i cannot get hard anymore. So i have been using finasteride for like 3 weeks every other day and if you did not know finasteride is a DHT blocker that helps with balding, everything was going fine until today,as usual i had taken my 0,625mg dose of fin the other night and when i woke up i had a sore throat so i pop a paracetamol pill and take some antibiotics, after that i fap and get a %75 percent hard on which is a bit unusal but i go about my day and it starts to bother me, why the hell did that happen so i fap again to check an this time my erection has become even weaker, every few hours i fap and it gradually becomes weaker and suddenly not a single increase in length for my compeletely flaccid penis. I am currently going [f***ing] crazy i have never been this stressed before when i try to fap my heart races like crazy and i feel like i have been put in a life or death situation. Please enlighten me what the hell mightve caused this sudden ED.

Post on r/Advice, 7 Apr 2021

Fin side after 3 days


Taking 1mg every other day.

Took it on monday. Next day my dick felt ‘weak’ could pull a semi.

Took it again on Wednesday, now on thursday and I can’t get hard at all.

I’m 20 years old and I’m about to dash my head across the wall

Post on r/tressless, 7 Jan 2021

[…] Yes I took two pills in total. But I haven’t got a boner since Monday. I absolutely swear to u I’m not thinking about it. All I’ve been focused on is work. Rn I’m looking at hot pictures and it is completely limp. I’m panicking. I’m 20 btw


Comment by original poster, 8 Jan 2021

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