Brain fog


Come on guys, nobody has gone through this wonderful side of propecia? Brain fog.
did you guys get it while on fin or after you quit. Do you still have it?
Do you notice times it gets better or worse and why. How long did it last?
Ive been able to beat mine but if I eat crappy foods, stress myself out physically or mentally it returns somewhat.
Any other?
lets get the ball rollin’


Hey there,

I am glad I found somebody else that have the same side effects as me. I recently decided to take propecia. I took it for 1 week. I know it was not that long but in that small period of time I noticed some sexual side effects like it was hard to get an erection and things like this. Also, after a week I noticed that my head started to hurt, I felt a little dizzie just not a good feeling. So, I stopped taking the pill. The sexual side effects went away but this brain fog that you call has not. its been about 4 weeks. I do not know if its b/c of the pills or something else but I have read about people that present the same brain fog feeling. I dont know how long you took the pill for or any details but it sure sounds something similar to what i have. I noticed that when lie down in bed the brain fog feeling tends to go away but it returns as soon as i get up and start moving. Well, I hope its a side effect of the pill and not somthing else.


Hey guys,
I experienced mental sides while on propecia. I took propecia on and off for 4 years and did not correlate my sides with propecia until I did a little research. Since quitting (3 months ago), I have noticed an improvement.

I did experience what is often described as “brain fog” but for me it manifested more as depression / anxiety. I am predisposed to mild depression genetically but I suffered major anxiety attacks while taking propecia.

I have included a study done on propecia and mood. My basic understanding is that the 5-alpha reductase enzyme metabolizes in the brain and finasterife being a 5-alpha inhibitor somehow can create mood variations in the people who take the drug. I have no science background and maybe someone else could help explain why this “brain fog” or mood disturbances can happen on fin.

I think that brain fog has to be correlated to people that get depressed on propecia…maybe if you’re not predisposed to depression / anxiety, the sides manifests as a brain fog and for people predisposed, it can manifest as anxiety and/or depression.

Nonetheless, I noticed a gradual improvement since stopping the drug but the tricky thing with mental sides is that they are hard to gage. I included the link to the study I referred to but it is also under Finasteride Studies on this forum. … id=1622749

PS: I am new to this site and was not on the yahoo group and I have to say this forum is amazing.


I have DEFINITELY experienced brainfog. It was so ridiculous. I never felt so stupid in my entire life.

I’ve read a post that mentioned that DHT actually is needed to feed certain nerves and the sudden decrease can cause brain damage. I wouldn’t discount that.

I’ve been off for one year now. I noticed improvement after 6-7 months of quitting.

VERY grueling process. Stay away from anything that can induce anything close to stress.


Its definately the propecia guys. It also gave me the inability to deal with any kind of mental stress, no matter how small. Its basically a poison if you ask me. In my case I didnt know about the Yahoo group and so it took me a long time to figure out what was going on with me. It was a complete nightmare. I kept thinking that maybe it was the propecia but everytime I looked up sides on the internet it kept telling me the side were rare and small. Lies. Thank God I found the Yahoo site.
In my case I laid off alcohol, sweets caffeines etc. It does help but may take a little while. dont stress out your livers either. Stay away from junk foods, fast foods etc.

Let me add that Im not pre disposed to depression. Before propecia I was such an easy going person, laid back etc.
During and after propecia I was an utter mess. Anxiety, depressed, brain fog…you name it.


How long did it take for finisteride to have the harmful side effects? I was on it for 1.5 years before things turned nasty (mental fog, dizziness, and 24 hr headches), but the doctors have labelled it new daily persistent headache


I think I was on it for a year or so when I started feeling the sides. I didnt know it was from propecia at the time, it occured to me several times but every time I looked up the sides on the internet it would just tell me the usual and I would believe it. One day merck will pay heavily for this shit.


I’m 25/male. I too experienced “brain fog” while on propecia and since I have quit. I quit about 9 months ago after being on propecia for about 2 years. I still experience mental fog once in a while. Sometimes I feel like I’m super intelligent and other times I feel like a retard. It is also more difficult for me to deal with stress. I am slightly depressed mainly because of the various side-effects I have been experiencing from taking propecia. I also noticed that I am less willing to challenge myself with activities that require thinking. I am more moody as well.

Is a test a doctor can do to figure out if propecia has affected my brain? On a side note, I talked to my friend who has done a lot of illegal drugs and he told me that it affected his mind but that his mind recovered. He is know a successful law school student. Maybe our brians can repair themselves from any damage propecia has done.


There is no question that finasteride can cause brain fog and other mental symptoms. Finasteride is a 5 alpha reductase inhibitor. It prevents the conversion of testosterone to DHT. DHt is 3-10 times more potent an androgen than testosterone. The 2 organs with the highest DHT receptors are the brain and the heart. This is not well known. Although the prostate and hair follicles have dht receptors and these are the 2 organs that the drug is supposed to target, big pharma and the urologists ignore the systemic effects which are sugnificant. DHt is also a potent vasodilator that works via the nitiric acid pathway. As you probably know, nitric acid is responsible for erections as well as arterial vasodilation. That is why viagra works (release of nitirc oxide) and why it can cause hypotension. It is my belief that people of finasteride will have a greater problem with pre existing
hypertension and may even develop new onset hypertension. Studies have not been done on this but it has been my experience on the drug. I am an antiaging physician also on finasteride and just recently started suffering the effects of the drug and discovering its pitfalls. I am getting off the drug after undergoing PVP for BPH.


Everything above I totally agree with – brain fog, mental side effects, feeling retarded, anxiety, dissociation, slurred speech, not being able to think fast enough when speaking, etc.

Also, the post above that says he noticed improvements after 6-7 months off is not the first time I’ve seen that number.


Hello all

I too suffer from brain fog etc. I rarely read about the times it has taken others to regain clarity after stopping use of fin. I would appreciate any insight from as many people as possible to determine any pattern.


Im posting here because i want anyone who is dealing with brain fog to realize that it is a real side effect and it is not all in your head. Let me start by saying ive taken propecia (generic) for years in the past and have never had any problem what so ever. This time was different. After about 8 days of taking it i started to just not feel like myself. It only got worse from that point. I had trouble reading, i felt stupid, I couldnt focus, had very little ability to pay attention during a conversation and when I was in public it was magnified by ten. Really it was worse when I interacted with anyone. I had to lay down most of the day because I felt dizzy and sick if i stood up. I felt so retarded that I had to focus on doing the dishes. I stopped using propecia immediately and the brain fog did not go away. Ok so now for the good news. YOU WILL GET BETTER. Trust me. If i can recover and return to my normal self anyone can! your body is very powerful and has the ability to restore itself to the way you were before you were experiencing brain fog. Its been about 4 weeks or so and I am truly feeling better. Id say about 95% or so. Please hang in there. I took a zinc once a day. I drank water with lemon all day long. Lemon cleanses the blood so i believe this to be very important. I also took coconut oil 3 times a day for the omega fats. Its very good for your brain. Please just hang in there. you are not crazy, you are not damaged , you are not going to be stuck like this forever. It just takes time to leave your body. That is all. if you have a question please feel free to ask. I know everyone thinks that they are experiencing it worse and that no one can understand what you are going through. I understand and i know what you are going through. YOU WILL GET BETTER


I have been off Propecia about 3 years now and still experience daily brain fog. Things that help: exercise, paleo diet has helped some also, staying hydrated. But no matter what, it is still there and my cognitive state is not what it once was. I am perpetually in a fog mentally, which is very frustrating and makes it difficult to live life as I once did. This has been the most difficult side effect for me out of all the other side effects.


Hi all. I am so glad this site exists… I want to say without a doubt Propecia has caused me intense depression and brain fog. The sense that things in the world were “fake” in a way… This all started to hit me 2 years after taking it. Before this experience I had always been very sharp and a happy go lucky guy. But then all went south, I started to feel hazy at first then noticed I just didn’t seem present in my life… Like it was all fake… It was a really weird and very scary experience… I saw online that some others had experienced this too and I stopped taking propecia immediately. It was a very long road back… It’s been a little over 2 years now that I’ve been off propecia and after a lot of work with therapy and yoga and soul searching I finally feel happy again… So now being the somewhat naive guy I am I started to think maybe I can try taking it again? Only to stumble across this discussion and remember how terrible my experience was. Literally I lost my job and my fiancée in this experience… It’s just not worth it. Thank you for these posts guys, this reminded me how awful the drug is and how scary it can be … I hope you are able to get back to where you were. My journey took two years of being off the drug, lots of exercise and yoga and therapy.


That’s so amazing that you said things were fake. When I was on that shit I kept thinking “this all feels like some kind of matrix like dream,” and I had no idea what was going on. Everything “felt fake” exactly like you describe! Unbelievable that I couldn’t see it was Propecia doing that shit to me.


I am still suffering this shit for 7 months and i cant see any end of it. Definitely some kind of braim damage… plus my vision is delayed like my eyes taking infos much slower than before.


Stay strong, depressedguy. The man who started this thread all those years ago is in the recovery section now.


It absolutely happened to me. I look back now - almost ten years from when I first took propecia - and regret the day the first tablet crossed my lips. I suffered badly from brain fog for years whilst taking it, it affected my job and performance - even got a ticking off from my boss for a few basic mistakes.

I gave up on propecia on for a while then went back on it in 2009/2010 without knowing these side effects and it just made me worse. The worst thing is the anxiety it is almost crippling and just destroys my energy. I can’t workout because I am too tired by the end of the day.