Dutasteride and Finasteride Dosage Discussion

Over the years I have read 100s of posts by hair loss sufferers who are uncertain about the most efficient dosage of finasteride (brand name Propecia) or dutasteride (brand name Avodart) to take in order to get the best possible outcome in terms of probable hair maintenance (and possible regrowth) versus risk of side effects. A few people have also e-mailed me with questions about this, but I usually refrain from responding or ask them to consult a doctor. Each person has a different risk tolerance. For many people, a 90 percent chance of hair maintenance (and maybe some regrowth) combined with a 10 percent chance of significant side effects is preferable to a 80 percent chance of hair maintenance combined with a 5 percent chance of significant side effects. For others, the reverse is true. Similarly, some people might be happy with a 60 percent reduction in dihydrotestosterone (DHT) levels, but others are willing to take a higher dose of a drug in order to get a 70 percent reduction.

The majority of people probably do not even look too deeply at finasteride or dutasteride related studies to try and find all the relevant statistics, and instead just prefer to experiment themselves or go with the doctor recommendation. Others are taking unusual doses (e.g., by cutting 5 mg pills into 4 pieces to get 1.25 mg) that are never covered in studies anyway. Furthermore, many people want to adjust the frequency of their drug intake to an unusual one (e.g., 3 times a week instead of 7 times a week) that is almost never covered in finasteride or dutasteride related studies. In this post, I will discuss some established dosage details based on published studies and data. Thereafter, I encourage people to comment on what dosage and frequency they have tried in the past, and what seems to have worked best. Scientific dosage related feedback is especially welcomed. I am also curious to hear what people think of taking their finasteride or dutasteride before eating versus after eating; in the daytime versus at night; alongside food such as grapefruit that can impact drug effectiveness; and so on.

Prostate v/s Serum v/s Scalp DHT Levels

Before continuing, one thing to note is that most studies on dihydrotestosterone (DHT) reduction measure serum (aka circulating/blood) DHT levels and scalp (aka follicular) DHT levels when it comes to hair loss related discussions. Prostate DHT level measurements are more common in studies looking at BPH, although many hair related studies also mention them. Both finasteride and dutasteride reduce serum DHT levels by a higher percentage than they do scalp DHT levels for all dosages it seems.

Finasteride (Propecia) Dosage Discussion

Finasteride was originally approved in 1992 to treat benign prostatic hyperplasia (BPH — which means enlarged prostates, a problem typically seen in older men). The finasteride dosage used for treating BPH is 5 mg a day (and the original brand name for this dosage version is Proscar (manufactured by Merck), although generics are now commonly used).

In 1997, the US FDA approved finasteride (at a dosage of 1 mg per day) to treat hair loss. The original brand for this product is the infamous Propecia. However, since Propecia was very expensive for many years when generic versions were not available (due to Merck’s now expired patent), people would buy the 5mg Proscar and cut it into 4 pieces and then take 1.25 mg of the drug every day. This strategy worked out to be a lot cheaper. However, note that there is no guarantee that a pill cutter is accurate enough to ensure 1.25 mg finasteride evenly distributed per quarter pill. Moreover, I have even read that the main ingredient in any pill is not evenly distributed throughout. So perhaps one quarter of Proscar could theoretically have 1.5 mg instead of 1.25 mg, while another could have 1 mg instead of 1.25 mg. I have no idea if such significant variation in ingredient distribution in a pill is common, but it does seem to have logical merit. When I used to cut generic 5 mg finasteride pills into four pieces a few years ago, I always lost some of the pill to crumbling/powder residue.

In any event, taking 1 mg versus 1.5 mg is not likely to be very different when it comes to finasteride. With dutasteride (see next section), small dosage variations have more of an impact. Finasteride is a type II and type III 5α-reductase enzyme inhibitor, meaning that it prevents the conversion of testosterone to DHT by the type II and III isoenzymes. However, it does not inhibit the type I 5α-reductase enzyme so DHT inhibition is not complete. At a dosage of 1 mg, finasteride results in a decrease in serum DHT levels by about 60-70 percent according to several studies I checked. The number for scalp DHT is a bit unclear, with several sources suggesting a reduction from anywhere between 40-65 percent. Prostate DHT levels decline by around 80-90 percent.

Whole doing research for this post, I uncovered something that I had not realized before. According to this study from 1999, It seems like Finasteride is almost as effective at 0.05 mg per day as it is at 1 mg per day or 5 mg per day when it comes to scalp skin DHT levels. And 0.2 mg per day is almost as effective as 1 mg per day or 5 mg per day when it comes to serum DHT levels.

Results quote from the full version of the above study:

Scalp skin DHT levels declined significantly by 13.0% with placebo and by 14.9%, 61.6%, 56.5%, 64.1%, and 69.4% with 0.01, 0.05, 0.2, 1, and 5 mg doses of finasteride, respectively. Serum DHT levels declined significantly by 49.5%, 68.6%, 71.4%, and 72.2% in the 0.05, 0.2, 1, and 5 mg finasteride treatment groups, respectively.

Another unusual study I found was this old one from 1990. They were testing up to 100 mg (!) per day of Finasteride in patients (for 11 days), which seems crazy.

Dutasteride (Avodart) Dosage Discussion

As I mentioned earlier, the biggest drawback of finasteride is that it does not inhibit the 5α-reductase type I isoenzyme, and therefore does not inhibit more than 70 percent or so (depending on dosage) of circulating DHT levels. However, in 2001, the US FDA approved a new drug called dutasteride (initially only sold under the brand name Avodart, with GSK’s patent on the drug having expired in 2015) to treat BPH. This new drug inhibits all three isoforms of 5α-reductase (i.e., type I, II, and III). As a result, almost all circulating DHT is eliminated (serum DHT levels decline by over 90 percent). This results in superior hair growth results in comparison to finasteride, but greater chances of side effects.

For men with BPH, Dutasteride is typically taken at a dose of 0.5 mg per day. Most hair loss sufferers also take the same dosage. While Dutasteride has been approved to treat hair loss in South Korea and Japan, the same has not yet occurred in the US or the EU as of 2017.

A person by the name of Dr. Richard Clark conducted some very important studies during the years immediately preceding and following the approval of Dutasteride for BPH that compared DHT inhibition from various doses of Dutasteride versus Finasteride 5 mg. Below are several highly useful charts from his studies. Note that in the first chart, the lower the better (i.e., greater DHT inhibition).

Dutasteride and Finasteride Dosage

Finasteride and Dutasteride Dosage and DHT Reduction

Linear versus Nonlinear Elimination

A few months ago, commentator “PinotQ” sent me an interesting e-mail that threw another twist into this confusing story. He also referenced this study from 1999. Key quote from his e-mail:

“FYI — About a month ago, I switched my avodart dosage from .5 mg per day to 1mg Monday, 1mg Wed and 1.5mg on Friday. Dutasteride has a non-linear elimination curve meaning the more you take at once, the longer the half life. At a dose of only 0.1 mg/day, the half-life is only around two or three days while at .5 mg it is 4-5 weeks. For this reason, my doctor suggested that 2 pills taken twice a week may be as effective (or more), than 1 pill per day. I am hoping for a little more powerful response going 3 times per week at 2-2-3 as I had read from Dr. Shapiro online that when switching from finasteride to dutasteride, to see renewed effectiveness, you would probably need to be at the 1mg per day dosage level………but this is just all educated speculation.”

Half-Life of Finasteride v/s Dutasteride and Side Effects

Dutasteride has an extremely long half-life of around 4 weeks. On the other hand, finasteride has a half-life of only 6-8 hours. Unfortunately, dutasteride also has higher side effect rates in comparison to finasteride. Most studies indicate that serious side effects are minimal when it comes to both dutasteride and finasteride (less than 5 percent of people get major problems, and even fewer get irreversible side effects). However, it should be noted that most people who are currently taking the more powerful dutasteride have only been doing so for less than 15 years since the drug was only approved for use in 2001. So we still do not know the really long-term ramifications of taking dutasteride.

 

101 thoughts on “Dutasteride and Finasteride Dosage Discussion”

  1. I read somewhere that even thou finasteride has a half life of 6 to 8 hours it forms a very strong bond with 5-AR, so for hairloss to continue developing new 5-AR molecules need to be synthesized, this takes 3 days to occur, so that would mean a dose od 0.2 mg taken each 3 days would be pretty much as effective as 1 mg every day.
    If someone could enlighten me about this subject Id be very thankfull.

    1. I heard from someone’s Reddit post that he tested his dht levels while taking finasteride and they only went up on the third day as well.

  2. There is a chart that can be found that tracks the serum levels of dutasteride when taken at .5mg per day vs. 1.5mg per day. The former takes around 60 days to reach peak blood concentration, while the latter takes only 10. I began with this loading phase and have noticed no side effects. From the drug (libido is actually increased from indirect testosterone increase via prevention of its conversion to DHT). Additionally, I take my .5mg daily at night just before bed, it probably doesn’t matter but I’ve read testosterone production peaks at around 1am and thus maximum prevention of DHT production would theoretically occur at night. Overall I’ve had at least a 30% increase in hair count and significant regrowth at the hairline from my 4 months on the drug combined with 15% minoxidil with little to no side effects and can provide pics for those weary of starting. Granted I am only 24 and began balding at 19. My hairline is now lower(!) than it was at 21, and though many of these hairs are still vellus, their density and thickness is improving every day. All the best, Mike

        1. Hi Mike, nice pictures!

          Did you use MIN 15% before you started taking pills?
          What effect did the MIN 15% have?

          If you started the drugs simultaneously, it will be hard to determine which drug actually did the trick for you.

          Thanx in advance

          1. I used both simultaneously, however I’m quite confident most of my results were due to the endogenous DHT suppression from the dutasteride, as I have used minoxidil on its own in the past without the regrowth of lost hairs. The two are synergistic and in comparison other topicals such as ketoconazole and even RU58841 will not hold a candle to the strength of internally suppressing DHT.

            1. I think you are right.

              I was just wondering whether it is helpful for people to jump from 5% MIN to higher doses. But is seems that even with higher doses of MIN, people are not being able to regrow lost hair. Only in conjunction with FIN or DUT regrowth will be possible/visible.

              I will stay with MIN 5% and keto shampoo myself.

    1. hey admin can you comment on Polichem ?
      what is their release date for topical fin?
      I’m not a fan of fin but I’ll give it a shot topically.

      1. Have not looked at them recently, but I know Hasson & Wong already have a topical Fin, and your local compounding pharmacy will usually make one for you. Mine sells 2-3 such orders a year in gel form if I recall, and it is somewhat expensive.

        1. I had no idea! I’ve been looking for what you just wrote for three years. I just contact my local compound pharmacy

    2. Hello everyone
      Friends, I am 35 years old, I use finasteride for 15 years when I have hair loss, I use regularly for at least 3 months by dividing the proscar tablet into 3 parts. And I am very pleased with its effect. I have a problem of baldness in my whole family, even my cousins ​​who are 10 years old have a problem of baldness, my shin hair is about 30 + 35 cm in thickness. The website is very nice and filled with useful information

  3. Hello ppl,

    recently started fin at 0,5mg per day… should I higher the dose or should I wait a year and then see whats up? Is 0,5mg even effective? cheers

    1. That will give you similar results as 1mg (around 60% DHT inhibition) but .5mg of dutasteride will inhibition up to 94%, and has a similar risk of side effects. In my opinion skip the finasteride and go with dutasteride, it has worked wonders for me and I haven’t noticed any side effects at all.

  4. I was on Propecia for total of 5 years at 1mg ED. The first year by itself with no results, no shedding, and no sides. I then added minox 15% 2x/day and had excellent regrowth all over. I would run my finger over my scalp and feel little hairs prickling everywhere. It peaked after 4 months but then tapered down below baseline after 4 years. I have just added Dutasteride a month ago at 0.5mg ED. I know it’s crazy but the first couple weeks my hair looked thicker to a point where i wife noticed as well. I’m now shedding some but not too bad…my hair does look thinner. This time however I can feel some sides with tenderness on my left chest which went away after 3 weeks in. I weight train 4days/week so maybe that helps alleviate the sides. My libido has increased and I feel my body is reacting to Dut much more than Fin. I’m hoping the reactions will lead to something positive on the hair…will see. If my hair recovers, i’ll take any sides any day. 🙂

      1. Whoa! All that growth in just 4 months? Very impressive! I’m even more motivated to keep going now. Thanks for the great pics Mike!

  5. Thank you Admin, your website is a blessing! I come here practically everyday finding up to date information and knowledge to help deal with this stupid hair problem we have.

    1. Thanks waiting, and please make sure to read the many useful comments in the Dutasteride testimonials page (link on upper right side of blog if viewing on desktop). Good luck with your Dutasteride use.

  6. I have used finasteride 1 mg daily dose at night for 5 years, but i stopped it for few months and few weeks . I am still on finasteride 1mg it slowed my hair loss progress but i did not notice any regrowth and it affected my sexual desire.

  7. .7-.75 its the maximum effectiveness dose for fin. Anything over this you are probably wasting the medicine. I take 1mg or sometime .5 one day and 1mg the next. .5 and 1 will balance out to .75

        1. It’s banned because it can hide steroid use. It doesn’t give you a performance boost. In fact the opposite. Finasterise causes an increase in estrogen levels. Dht is an important part of the feed back loop to mai training a balanced hormonal profile keeping estrogen levels low.

                1. I get that, but all i’m saying is that finasteride isn’t something that will provide a boost for athletic performance unless you can block the estrogen rise. If estrogen goes up, the feedback loop would be to decrease testosterone to reduce estrogen.

                  In addition, DHT is thought to aid in muscle development indirectly. I know its not used in muscle tissue directly but its thought to provide the neurological bridge to enhance muscle development.

                  I’ve personally have used finasteride and my personal athletic performance (soccer) has been better off the drug. In addition to weight lifting results, finasteride in my case, has been a detriment. of course my observations are not scientific so take it with a grain of salt but there isn’t evidence that finasteride yield better athletes other than theorizing higher testosterone while ignoring the other side affects and negating the benefits of DHT.

                  1. If finasteride truly were beneficial, every professional athlete would be on it and none of them would be bald, which clearly isn’t the case.

                    This whole testosterone boost is nothing more than a selective data process to validate the safety of using propecia. If it makes you sleep better at night, than by all means but its not the reality that we all live under.

  8. My dermatologist put me on Dautastride .5mg/d.
    I was noticing some thinning in the front area + about 10 hairs fell out daily. what Dautastride made with my hair was unbelievable. after just 4 months I noticed that I had one of the most beautiful and healthier hair in my city. but what surprised me is that my doctor who is noe of the best Profs in my country when it comes to dermatology and hair transplantation ( USA board) did not tell me any thing about the side effects of this drug. I remember when he recommended it to me, I aked him and told him that I am worried about Dauta side adverse on sexuality .. etc.
    however his replay was “this is an FDA-approved drug, and it is safe enough to be on even for lifelong”.
    now let me be more precise just to convey my experience to anyone who is considering giving Dauta a try:
    Pros :
    – hair shedding = 0
    – falling down = 0
    – thickness = folded by 5 at least
    let me say that my haie became heathier , stronger,and thicker than my sister hair.
    Cons :
    – severe deprission ( to the point of thinking about suicide)
    – sexual dysfunction ( lost desire + very weak erection + libido texture changed to be almost water).
    – there were some behaviours of feminization ( new hair style + new wearing habits + …etc)
    I was on Duata for 4 months. cut off for about 2 months as I had noticed the side effects mentioned above. then used it for about 1 month before taking it to the closest garbage container.

    1. Man you could send me the rest instead of throwing it ! People can’t offord buying medications and you are just waisting it. Hate when people talk bad about fun and dut :/

  9. I am on 10mg of dutasteride and i am still not maintaining. Still receding and shedding around 75-100 just showering. No sides at all. Certain genotypes must not have any effect from internall aa’s

  10. Im taking half a fin tablet and 1 whole dut a day. Been on fin about 6 years and dut 3 years. Semen is watery but libido is about the same as it ever was. It was increased when i started dut but its tapered off now.

    My hair has been slowing getting worse, but its been slow. Im 41 years old now. I still have about 65% of my hair. Getting very thin in the back and hairline is receeding, but i almost guarantee i would be a very high norwood today if i hadnt been using these drugs. They bought me some time, but i think the effect has about run its course

  11. Admin, i know this is off topic but wanted to mention this to you. A few years ago i tried topical indomethacin. I went from losing 100+ hairs a day to 5 hairs within 3 days!
    Unfortunately it caused intense scalp irritation and i had to quit.
    I’m not sure exactly how it worked but while it did it was super effective at stopping hair loss.

    1. Indomethacin is an anti-inflammatory drug.
      To a certain extent, it can lead to immunosuppression.

      It works against joint pains, rheumatoid arthritis and psoriatic disease symptoms.
      Local adverse reactions (irritation/rash) may occur when patients use it topically.

      Again the role of the immune system comes into play here.

      1. It most definitely cause irritation and rash but I promise you my shedding almost completely stopped over that week and a half.
        Wish there was another substance that acted in a similar way without the sides

  12. I’ve been hesitant to consider these drugs due to the risk of side effects. My wife and I are having our first child soon, so I’ve steered clear of anything that effects fertility. The positive experiences recounted in the comments surprise me.

    What are the wider endocrine effects of the drugs? Does 5α-reductase enzyme inhibition cause increased serum free testosterone levels? I’ve read conflicting reports. Also, my doctor told me DHT was the most “active” form of testosterone, so I assumed that applied to the formation and maintenance of muscle mass, etc.

    I know this is only tangentially related to the topic, sorry.

    1. Dht is more potent than testosterone in many tissues but… not muscle mass. Testosterone is better than dht for muscle mass

  13. This is good information to have, in regards to DHT suppression from various dosages. However, I believe that mass interest in future hair loss treatments is to find one that doesn’t disrupt or inhibit naturally occurring hormones that play an in important role in the male body. There are many tissues that are dependent on androgens for normal function and maintenance.

    Suppressing dht can be compensated by some, but not all people, and for a certain period of time, not indefinitely. The whole notion of merely a 2% side effect profile is laughable as is the 13% dht suppression on a placebo! If DHT suppression were safe and generally an accepted medical practice why wouldn’t merk market this drug to every man over the age of 18 as a vaccine to prevent every ailment caused by DHT. It could be packaged as part of a routine intake of daily supplement along with vitamins and minerals.

    Truth is this stuff works but it’s like using a blow torch to light a candle. Screwing with your hormones shouldn’t be done so callously. Many like myself who can’t tolerate this stuff are wondering how many are out there taking this stuff, get side effect but are so desperate for hair that they just don’t care and keep going?

  14. I’m a doctor and I take 0.25 mg propecia every other day. Started almost one year ago. Noticeable thickening and regrowth at the temples. I’m glad I started taking it. I may increase the dose to daily sometime this year.

  15. I think there was a mistake. New studies in 2017! Admin I think the post is “inappropriate”.
    a) Association of Suicidality and Depression With 5α-Reductase Inhibitors (2017) – .
    https://www.ncbi.nlm.nih.gov/pubmed/28319231
    It is proven this drug create depression! These studies DON’T LIE. Publishing to the Pubmed database is not easy.

    b) Syndrome post- Finasteride IS REAL.

    Persistent erectile dysfunction in men exposed to the 5α-reductase inhibitors, finasteride, or dutasteride (2017)
    https://www.ncbi.nlm.nih.gov/pubmed/28289563

    c) Post-Finasteride Adverse Effects in Male Androgenic Alopecia: A Case Report of Vitiligo.

    https://www.ncbi.nlm.nih.gov/pubmed/28222425

    Sincerely, I believe that Follica (RAIN) must be approved by the FDA as soon as possible, as well as other treatments such as Brotzu Lotion or other alternatives to treat androgenetic alopecia safely and effectively than current treatments.

    Thanks for your time.

    Paul Pheonix

    1. Its the increased estradiol. Search for estradiol side effect profile which includes tender breast. Need to have low bodyfat and eat your veggies. Cruciferous are proven to flush estrogens quite a lot in studies.

      1. Inhibition of 5α-reductase results in decreased conversion of testosterone to DHT, leading to increased testosterone and estradiol. Need to also include ways to reduce estradiol in your regimen or risk the side effects.

    1. Dear Dr Paul ( hair transplant surgeon) stop posting these stupid stuff , you won’t fool anyone by this.

      Thanks

      Unti HT doctors

  16. Been on fin .25 everyday for 4 months…had sides the first 2 weeks then they went away….only side i have now is puffy nipples n sometimes chest pains when i drink alcohol the next day..as for my hair im just shedding less..im a week in to taking .5 ed..

  17. I was on 1 mg Finasteride for close to 20 years, my pecker went dead, I became depressed and committed suicide. That was for Paul, but seriously I noticed little to no sides and was effective for 15 of those years. Started to lose ground, switched to dutasteride a little over a year ago. Again, no sides with the exception of some increased horniness the first 4-6 weeks. Has halted the increased shedding I was having but no re-growth.

    1. What exactly do you mean by lose ground? Did you drop below baseline or did you just notice increased shedding? Do you have pics to document your progress that you can share? I’m fairly new on the drug and it has worked wonders so far so I would like to see how it worked for you over that long time. Also, my dermatologist who prescribed me it has been on it for a long time and I couldn’t even tell he had any hair loss.

      1. Increase in shedding = drop below baseline and haven’t recovered after switching to dut 1.5 years ago. Don’t try to compare my current situation to yours, you are “fairly new” on the “drug”. I was close to 20 years on 1mg of fin and had a good run. I’m an old duffer, 54 started to lose it at 17. I’d be horseshoe bald by now, still an NW 3, maybe 2.5 on a good day. Keep the faith Danny Boy! No pics, I rarely post, consider yourself enlightened by Yoda. 🙂

    1. Just having a low bodyfat% such as less than 8% will go a long way. Extra help: black tea extract, black tea, ( take decafeinated) which seems to have much greater inhibition of aromatase than the green variety. I also take many “purple” veggies such as purple sweet potatoes, grape seed extract, epicatechin, fava beans, apple extract sometimes.

      Honestly low bodyfat is probably enough.

        1. At the end of the day taking fin is like a different and weaker version of taking steroids due to hhe increased testosterone. Bodybuilders take aromatase inhibitors and have low bodyfat. Many people get erectile disfunction and gunecomastia (boobs) from taking anabolic steroids.

          1. but those body buildiers aren’t inhibiting DHT. in fact many who have tried are reporting diminishing returns and are realizing that dht is an important androgen for male and musculature development.

            This isn’t steroids. this is a drug that CAN be used to transgenders to change sex.

            I’m not trying to tell people to not use propecia. if you do and it works without side effects, great! but dont be surprised if it doesn’t. after all, you are blocking an important hormone, and those complaining about side effects shouldn’t be scoffed as psychosomatic.

      1. Ya, i have a body fat percentage of less than 8%, i’m a semi pro athlete, i don’t get gyno on fin but i do have ED when using Fin. i’ve tried estrogen blockers short of arimidex, and it doesn’t work.

        i dont think low body fat isn’t going to fix ED.

          1. What is your regimen? Are you substituting fin for a non-permanent inhibitor? Those seem to work the same but have less sides. I need to look into these.

            1. I don’t do anything other than use minoxidil foam to slow down hair loss, and cut my hair short or buzz it. Without finasterise it’s a done deal, but at least my junk works great again.

              Non permanent inhibitor? no I have not.

  18. Guys do you think the BIG 3 treatment is effective for a rapid diffuse thinner like me? I would tend to think that diffusers are the best responders to fin and minox because its easier to grow hair where there is some left, nevertheless I wanted you’re opinion on this one… for I really need motivation in continuing this journey…

    Thank you

      1. Nothing new on a release date but it sounds like they are starting to try and generate advanced interest in the dermatology community for the office procedure. I’d like to think this will be far superior to derma rolling + minox but I guess that all depends on the magical additional components. They did say that they are trying to ensure the office procedure does not require a shaved head which is good for the low norwoods.

  19. Hi admin,
    I have been taking fin and was thinking of switching to dut. But my dr refuse to prescribe as it is not fda approved and unknow side effect maybe.

    I hv been reading for months here and read some very succeasful comment about dut, so i would like to buy online.

    Before that may i know what combination are u using to deal with yr hair problem?

    Maybe u hv mentioned somewhere but i missed.

    Thanks!

    1. Hi Kev, I have been taking 0.5 mg Dutasteride for a few months now. Initially, it was once daily. Lately, once every two days. I think it has helped my crown region get thicker.

      Please follow your doctor’s advice, and if you ever do start taking the drug, make sure to use a reputable pharmacy. I try not to recommend any online pharmacies and it is up to you and your doctor to decide what to risk.

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