Dutasteride (brand name Avodart) is superior to Finasteride (brand name Propecia) when it comes to hair growth. See my old post on Dutasteride for hair loss reviews for numerous reader testimonials.
However, there is a massive difference in Dutasteride’s effectiveness in reducing serum dihydrotestosterone (DHT) levels versus the more relevant scalp DHT levels.
Dutasteride Scalp DHT Reduction of only 50%
While Dutasteride 0.5 mg/day lowers serum DHT levels by over 90 percent, it only lowers scalp DHT levels by around 50 percent. Per a widely cited 2006 US study from Olsen et al, Dutasteride 0.5 mg per day suppressed serum DHT concentrations by 92% and scalp DHT levels by 51%. Meanwhile, Finasteride 5 mg reduced serum DHT levels by 73% and scalp levels by 41%. Full study is here.
Perhaps of more interest, Dutasteride 2.5 mg per day suppressed scalp DHT levels by 79%. See the below chart (front the Olsen study) and its X-axis. Note that for hair loss, the recommended dosages are 1 mg/day for Finasteride or 0.5 mg/day for Dutasteride. For benign prostatic hyperplasia (BPH), the recommended dosages are 5 mg/day for Finasteride (brand name Proscar) or the same 0.5 mg/day for Dutasteride. The half-life of Finasteride is 6-8 hours, but a much longer 4-5 weeks for Dutasteride.
I am a bit too wary of side effects and currently just take 0.5 mg/day of Dutasteride twice a week (instead of daily). In reality, if you truly do not care about side effects and really want to risk it, 2.5mg per day or higher seems to be the way to go. I would never go that far, tempting as it is. Most doctors will also be unwilling to prescribe you such a high dose.
While writing this post, I notice that the above Olsen study from 2006 has been referred to in many later studies and reviews. But there seems to be little to no new research on Dutasteride’s impact on scalp DHT levels. This is quite surprising, and if you find any such newer research, please post a link in the comments.
In the Olsen paper, 416 men from ages 21 to 45 years were randomized to receive: Dutasteride 0.05,
0.1, 0.5 or 2.5 mg; finasteride 5 mg; or placebo; all daily for 24 weeks. So it was a decent sample size.
Are Injections and Topicals more Effective at Reducing Scalp DHT levels?
This realization has made me evermore curious about mesotherapy with dutasteride (aka dutasteride injections). I wonder how much more effective a direct scalp injection is at reducing scalp DHT levels? I suppose it depends on the dosage and frequency of the injections.
I also wonder if topical Dutasteride and topical Finasteride can reduce more scalp DHT in comparison to their oral counterparts? This would be very hard to study, since so many companies now produce their own versions of topical Fin or Dut.
Note that while Finasteride is a selective inhibitor of the type II and type III isoforms of the 5α-reductase enzyme, Dutasteride inhibits all three isoenzymes of 5α-reductase. The latter grows more hair than the former, but also has a higher chance of giving you side effects. Most studies suggest that serious long-lasting side effects occur in less than five percent of patients.
Interestingly, both oral Finasteride and oral Dutasteride impact estrogen and testosterone levels in a similar manner in the average adult.
Stuff is pure poison. The anxiety and muscle twitches I got from finasteride lasted months and months, some of the darkest periods of my life.
The level of cope I see on various fora about the effects of finasteride is amazing, really does make me think raised estrogen is impacting guys’ emotions. If the trade-off of more hair is worth chemically castrating yourself, that’s a legitimate stance to take, just own it.
Not taking it must affect one’s grammar and ability to structure sentences properly. Such BS and scaremongering. Maybe for you, not for all.
Sort of proving my point here…
Wild take man. Did you ever for a second consider that maybe not everyone gets side effects? The amount of people here that are so self centered they bash other people for taking something because they assume it has the same impact on everyone.
I’ve taken fin and currently take dut. My hormone levels are healthy and those of a 20 year old (I’m 30) along with all of my other biomarkers. My dick works fine, I shoot ropes, and my athletic performance is great. All that plus I’m keeping my hair. Glad I was never deterred by cry babies on the internet saying it was going to “castrate” me hahaha
That fin produces effects comparable to castration is documented – https://www.nejm.org/doi/full/10.1056/NEJM199210223271701
No idea how you reached that conclusion from that study. It just compares serum DHT level reduction to castration. Not testosterone.
Interestingly, they have even tested 100 mg per day Finasteride in humans for 11 days:
https://pubmed.ncbi.nlm.nih.gov/2156887/
“Approximately 50 percent of the men who received finasteride had a decrease of 20 percent or more in the size of the prostate, a response similar to that reported in men treated with…surgical castration…”
It also seems a bit simple to characterise what I’ve written as “everybody will experience x”, when it’s convention in discussions RE: medical treatments to consider what most people can expect.
Yes, because it’s reducing DHT. DHT is the cause of Benign prostatic hyperplasia (enlarged prostate) and is often treated with propecia.
Of course castration reduces DHT. Castration however also reduces testosterone, which finasteride actually slightly increases.
Are you new here?
Fair enough, finasteride is not producing exactly the same effects as castration, but do you imagine the only identical effect it produces is reduction of prostate size?
True dat Joe, I started on fin off label in the mid 90’s before propecia was released, now on dut, no appreciable sides. The “everybody will get castrated” crowd is the same as if I said absolutely no one will ever have a side effect, just not true. Misery loves company I guess.
100%. To those who experience side effects, 5ar inhibitors basically castrate and lobotomize the individual.
How can one call it a ‘side’-effect though, when the drug primarily functions to shrink the prostate through androgen inhibition?
Tom BS you’re lying or have some other problem lol. I highly doubt its from dutasteride. Stop scaring readers.
Not lying, just stating my experience brother. Hope it goes well for others but I would advise against it.
Quick chatgpt search will actually find studies supporting higher scalp dht suppression (65-69%) with finasteride (1 or 5mg) use than dutasteride (0.5mg) (51%).
Yeah I mentioned one such 1999 Finasteride study in the below 2017 post, but the 2006 Olsen study seems to have become the most cited one when it comes to Dutasteride. And older studies could not cover Dutateride, since it was only approved in 2001.
https://www.hairlosscure2020.com/dutasteride-and-finasteride-dosage-discussion/
https://pubmed.ncbi.nlm.nih.gov/10495374/
It is hard to believe that Finasteride 1 mg/day can ever reduce a higher percentage of DHT than Dutasteride 0.5 mg/day (serum or scalp).
You would think that topical delivery of Dut would have a better chance at reducing scalp DHT. From the dosing regimens I saw in a few studies, most seem to start with once a week for a month, then once every other week, then once a month…….which would seem to indicate that Dut stays in the scalp and ramps up over time due to the 4 week half life. While I found multiple studies which appear to indicate topical Dut mesotherapy actually works, the studies seem to focus more on having the advantage of less side effects rather than whether it is more effective than oral. It makes me contemplate cutting back on oral to a few days a week but supplementing with topical Dut/microneedling. Here is one such study on mesotherapy: http://www.odermatol.com/wp-content/uploads/file/2013%201/9_Evaluation%20of%20the%20effect-Sobhy%20N.pdf
The title of this post is misleading, since it only refers to 0.5 mg Dut. As shown in the study, higher doses provide greater supression. I would love to see research measuring the impact of topical Dut on scalp and serum DHT, but unfortunately it doesn’t exist.
Personally I’ve been using topical Dut for several years now and it seems to have completely halted my hair loss. I currently use ~5mg a day. I’ve had my serum DHT levels tested multiple times under multiple doses, and this dose of 5mg has reduced my serum DHT by ~40%. I went up to 9mg at one point and saw serum DHT down by ~60%. However there’s substantial variance from test to test even with the dose held constant, so don’t take those numbers as perfectly precise. But this does confirm that, contrary to what some suggest, topical DUT.
I am sensitive to DHT blockers, Oral 1mg Fin caused my semen to coagulate and made ejaculation painful. I stuck with it for a month but finally gave up as the side effects weren’t diminishing.
I’ve had no side effects on topical Dut. At my dose, presumably very little is getting into the prostate and other reproductive organs. Keep in mind serum DHT is mostly produced by the liver, so it doesn’t accurately reflect DHT levels in the prostate or other organs.
iLoveDut, What brand of topical Dut do you use? The meso therapy in the study I sited above used 1 mg per treatment which was once a week for 4 weeks, once every other week for 2 more sessions, then once a month. As you point out, the study confirms the higher dose got better results. I have read that the molecular weight of Dut is 528.53. I have seen some studies say the molecular weight needs to be under 500 to penetrate the scalp……others say the range is 400 to 700. It apparently penetrates the scalp for you. I currently use oral Dut but am considering a switch to topical. Perhaps daily, or maybe once a week with microneeding or maybe a combination. Any details would be appreciated.
iLoveDut,
I would guess that over 95% of hair loss sufferers who take oral dutasteride take the 0.5 mg/day dose (or even lower, as in my case of twice per week). I also can’t have very lengthy titles explaining all the dosage iterations, as Google dislikes the appearance.
In the post, I do mention in bold the 79% DHT reduction with higher-dose dutasteride.
I am more interested in topical dutasteride and dutasteride injections now, assuming less system absorption.
PinotQ – I use Happy Head. The standard formula (0.3% dut). I apply ~1.5ml at night, and a little along the sides of my hairline in the AM.
The 500 Dalton Rule is misunderstood by some. 500 Daltons is where absorption starts to decrease, not the point at which absorption is impossible.
If oral Dut works for you, great. I do have concerns about the long term effects of 5AR inhibitors. Topical Dut is my compromise solution – it stopped my rapid balding, I’ve had no side effects, and if it’s only decreasing serum DHT by <50%, then clearly not very much is going systemic (it must be well under <10% given 0.5 mg oral provides ~95% reduction).
admin – understood, I just found it a little clickbaity, probably not your intention. Thanks for your work on the site, I've been reading for years. It's disappointing no one has collected data on topical Dut and scalp DHT… really shouldn't be that hard.
Interesting, thanks for sharing. How does the topical dut compare to your experiment with oral fin in terms of efficacy? And so you are confident about it being effective, and it not reducing serum dht by more than 50%?
Thanks iLoveDut. That’s a helpful distinction and I guess it can vary from person to person. It obviously works for you because you have measured a reduction in serum dht. In researching this, I also found that the stratum corneum, which is the top layer of the scalp, is what is primarily responsible for reducing/preventing absorbtion of larger molecules. It is apprently no thicker than one half of .1 millimeter. For perspective, the optimal scalp microneedle depth is believed to be around .7 or .8 mm but you probably shouldn’t microneedle at that depth more than once a week (Follica had published that the optimal interval was every 2 weeks although every week was the next most benefical interval). But I’m guessing someone could microneedle at a depth of somewhere bewteen .3 and .5 two, and maybe 3 times a week…..if they were inclined to try and increase absorbtion. Great post by Admin to highlight the scalp dht issue……………..I have never really given topical dut any thought since I don’t have sides with oral.
Is scalp suppression really the most important thing here though? What if you only have to shield the dermal papilla? Science shows that finasteride at 1 mg blocks about 40% of DHT in the scalp, and about 64% in the papilla. The data also shows that 0.5 mg of dutasteride blocks blocks 50% of DHT in the scalp of 92% in the papilla. Perhaps to get to 100% protection of the papilla, it would be as little as 8 to 14 dutasteride 0.5mg pills per week?
Reference:
https://www.youtube.com/watch?v=eqot_S83RnM&t=862s
Good link kp. I listened to it and one possible reason that topical dut might have an additive effect is that it says that higher concentrations of dut in the hair (scalp) were associated with a more significant reduction in DHT. So while .5 mg of oral Dut might block 92% of DHT in the papilla, and that might be enough for many/most to maintain or get some regrowth, if that isn’t enough or if you are slowly losing the battle over time, maybe the additional reduction from the use of topical dut would help. The link goes on to say (at 15:15) that by taking 2.5 mg vs .5 mg of oral dut, you wil see an additonal reduction of scalp dht of between 50% to 80%…..perhaps more if applied topically. Since a topical concentration of .05% gives you .5 mg of dut per ml, it would almost certainly have the potential for less side effects since it likely wouldn’t all go systemic.
See this study where the combination of topical minox, oral Dut and once a month micro needle of topical .02% Dut was more effective than topical minoxidil and oral Dut alone: https://academic.oup.com/qjmed/article-abstract/117/Supplement_2/hcae175.207/7903544 I find it interesting that a once a month or even a once a week application of a DHT inhibitor could have much of an effect. I don’t have the full study but this would seem to suggest that topical Dut provides additional protection.
In this study, topical Dut was not added as an add on to oral Dut, rather it was a head to head comparison and the topical formulation showed superior results. I don’t believe I’ve seen that result until now. An unfortunate complicating factor in going forward with topical Dut is the wide selection available of formulations with no knowledge of relative efficacy.
You have companies like Xyon selling topical DUT with some fancy delivery mechanism for a fortune. I guarantee you if they had any evidence that it actually worked in suppressing scalp DHT they would be shouting from the roof top about it. And given the doctors involved in that company I am sure they have tested it. In fact under their FAQ they answer the question “does topical dutaseride work” with a bunch of facts about oral DUT. Stay well away from them. If you want to test topical DUT go with the cheaper, less BSy sellers
@admin do you feel 2x week Dut is effective for you?
Do you take fin on other days and if not did you switch from fin? And if so has Dut been more effective in your experience.
It was working for years, but gets less effective each year now.
I only take Oral Dutasteride 2 days a week and Oral Minoxidil 7 days a week. I switched from Fin to Dut many years ago… maybe close to 10 now, but I forget.
Check out my old posts on generic Dutasteride for more information.
Thanks for pointing that out John. I mis-read and that makes me want to give topical a try even more. Since oral dut gradually started no longer maintaining several years ago, I am not sure what I have to lose by trying mcironeedle + topical dut once or twice a week. I can simply replace .5 oral mg 1-2 days a week with topical. That should theoretically translate to less systemic absorbtion while increasing potency where needed the most.
You’re welcome, Pinotq. I agree, this study really makes me want to get Dut topical. I wish we knew the precise topical formula used in the study.
I hate to say it…unfortunately everything that’s currently available gets less effective each year. It’s just a question of how much less and how long it takes.
Other than for Japanese men on Finasteride :-)
https://www.hairlosscure2020.com/does-finasteride-work-after-20-years/
100% agree
John, The study stating that topical dut outperformed oral used a .02% solution once a month with microneedling. I don’t think I posted this before so here is another study finding that used .05% with other listed additives (see group B under methods). This study was based on once a week for 4 weeks, then once every other week for 1 month, then once a month for 3 months. My understanding is that mesoptherapy differs from microneedling in that the injections go a little deeper and are combined with a cocktail of ingredients. FYI, I have always used the calculator in the link below to determine mg per solution. I have already started using one .5mg dut gel tab. I squeeze the liquid into 1 ml of alcohol = .05%…….so a gel tab on the scalp twice a week with microneedling vs a .5mg gel orally.
https://www.physiologyweb.com/calculators/percent_solutions_calculator.html I have a consult Monday to buy .05% from a compounding pharmacy.
Could you post both studies? Thanks a lot.
Thank you for posting this, Pinotq. I received a prescription for oral dutasteride recently, but based on these studies I’ve ordered topical instead. I’m excited to combine microneedling with topical dutasteride and see what happens.
Here are the studies: https://academic.oup.com/qjmed/article-abstract/117/Supplement_2/hcae175.207/7903544
https://www.odermatol.com/wp-content/uploads/file/2013%201/9_Evaluation%20of%20the%20effect-Sobhy%20N.pdf
I forgot to mention that in the Meso study, while the solution was .05% of dut (.5 mg per ml), the application was of 1.5ml to 2 ml meaning they applied .75mg to 1 mg of dut per application. They said that none of the subjects complained of decreased libido or ejaculatory dysfunction. I have been at this so long the odds aren’t great that topical it will have a significant effect on me but I like staying proactive so I am giving it a try.
Thanks. I really want to know the results of the this trial, but cannot find it anywhere… https://www.clinicaltrialsregister.eu/ctr-search/trial/2022-001802-23/ES
In doing further homework on topical dut, it appears the overwhelming consensus is that oral dut is a stronger hair loss medication than topical……..this according my doctor who just prescribed topical dut for me. That’s also what you’ll hear from ChatGPT. However, ChatGPT also says that there is emerging research that topical dut combined with microneedling out performs oral dut. It makes sense that microneedling is a real difference maker when you consider the larger moleculer size of dut as it likely doesn’t absorb well in most people although individual scalp chracteristics and enhancers can help improve efectiveness. It would also seem, based on the studies cited above and the mesotherapy studies, that once in the scalp, topical dut has some staying power given the long half life……potentially making a bigger difference in the scalp where needed most. I’ll be trying a combo approach and see what happens.
HairDAO is developing a topical dut. The vehicle study will be done this month. You may be interested in that.
Thanks for the update , Pinotq. What depth for the microneedling instrument seems to be the best based on what you’ve read?
The Follica research says that the optimal depth is .8 mm every 2 weeks (Summary below). The next best interval was every week. But for topical dut with Meso/Microneedle, the trials seem to be deeeper: 1 mm to 1.5 mm. At those depths, the interval should probably not be over once a week. I have started with .8 once a week and .5 once a week (twice per week). In general, the research seems to suggest you can do up to 4 times a week at depths of .5 mm down. Remember, I am not a doctor…just a guy doing as much background work as I can to craft a plan to test out some of this early stage emerging research.
Follica Summary
• The primary target is to produce 1600 thin needle wounds per cm² every two weeks (their preferred parameter configuration is: using a 12 needle head (2 rows with 6 needles) with a width of 0.9 cm at a movement speed of 2 cm per second and an osicllation speed of 120 Hz)
• Needling device: electric dermaneedling device. They specifically state that dermarollers and dermabrasion devices are less effective. About dermarollers they write that tearing and cut-like wounds are ineffective for neogenesis and that one has to aim for real, “pointy” needle wounds without any tearing or cutting.
• Needle target depth: 0.8 mm. For long hair, this can be increased to 1.0 mm, but definitely not more than that. The wound should extend 0.8 mm into the skin but not deeper, 1.0 mm is only to compensate for longer hair.
• Needling frequency: Once every two weeks produces the best results, followed by once a week, followed by once every 4 weeks
Good stuff thank you.
Here is another study (I believe Admin has posted before) where dut and min were tatooed (once a month for 3 months) into the scalp with a “rotatory tattoo machine (Cheyenne, MT.DERM) set at 120 Hz using a 27-needle cartridge (3240 perforations/s) at 1.5-mm needle exposure was used to deliver sterile-compounded 0.5% minoxidil sulfate (1 mL) and 0.1% dutasteride (1 mL)”. 12 of 15 males subjects had 10% or greater increase in scalp area regrowth. These were subjects who had “a lack of response to topical minoxidil and oral 5-a-
reductase inhibitors for >6 months”. So this looks like another indicator that dut can be microneedled into the scalp at intervals of no more than monthly with greater efficacy than oral dut. This was only a .1% solution but note that the needle depth was a deep 1.5 mm. ChatGPT says that with microneedling, the medication can penetrate deeper, potentially increasing retention: Here is the rest of the summary:
Key Findings:
Enhanced Efficacy: Combining microneedling with topical dutasteride has been associated with increased hair density and thickness, suggesting synergistic effects.
Reduced Frequency: Some studies indicate that even with less frequent applications, such as once a month, this combination can be effective, potentially due to the enhanced absorption facilitated by microneedling.
Safety Profile: The combination therapy has been generally well-tolerated, with most adverse events being mild and reversible.
These findings suggest that microneedling combined with topical dutasteride is a promising approach for treating AGA, offering potential benefits even with reduced application frequency.
Thanks. You will probably be interested in hairdao’s study results in 2 weeks.
Thanks for posting this, keep em coming Pinotq. I received topical dutasteride from Maximus Tribe with instructions to apply daily. Now of course I’m wondering if I should apply less frequently. 10% increase in hair growth ain’t much as has been noted, but I’ll take it if it happens.