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.
Dutasteride and Finasteride Scalp DHT Reduction. Olsen et al (2006). The American Academy of Dermatology
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.
20 Year Results from using Dutasteride for Hair Loss
An excellent new 2-hour plus interview on the HairStacks podcast with “John”, who has taken Dutasteride for 20 years to treat his hair loss. The results are quite respectable and he seems to have maintained all his hair and perhaps even seen some thickening. He also takes the anti-androgen Spironolactone to treat his high blood pressure. Note that Dutasteride has not helped prevent his hair from greying moderately. On a related note, check out my post on great long-term results from Finasteride in Japanese men with androgenetic alopecia.
In the below lengthy interview, they discuss a ton of other subjects, including: Minoxidil Sulfate; peptides; androgen receptor targeting new drugs such as KX-826; Amplifica; Follicum; the arrector pili muscles; and more. “John” even mentions the late Bryan Shelton! Note that “John”, who is in his early 50s, also gave a much shorter interview to HairStacks one month ago.
February 26, 2018
I have an especially keen interest in the drug Dutasteride (brand name Avodart) because it is currently the best option to treat hair loss if you are willing to tolerate the potential side effects. My post on Dutasteride for hair loss reviews now has over 400 comments, with a surprising number of people reporting great hair growth results. Dutasteride is significantly superior to Finasteride (brand name Propecia) when it comes to reversing hair loss.
Note that Dutasteride only approved to treat hair loss in Japan and South Korea. In the US, you need to get it off-label for hair loss, although it is approved to treat benign prostatic hyperplasia (BPH).
In the past, actor Ashton Kutcher tackled his hair loss with Dutasreride (Avodart).
I have been taking the drug for almost two years with good results. However, a few months ago I reduced my dosage to 0.5 mg once every other day (half the recommended 0.5 mg per day). I think that I may have gained some body fat while on Dutasteride.
Moreover, I have recently seen a sudden appearance of significant forehead acne after starting to take generic pills from a different manufacturer (since my local pharmacy switched suppliers). Dutasteride moderately raises both estrogen and testosterone in those taking it, so the side effects I am getting are not surprising, so I cut my intake frequency. I also wanted to reduce the daily processing load on my liver.
Celebrities Never Mention Taking Avodart for Hair Loss
We have all heard of 100s of celebrities and athletes who have admitted to using Propecia (Finasteride) to combat their hair loss. The most recent case was US President Donald Trump. I still cannot believe that on the official White House website, it says that President Trump uses Propecia for his hair loss. The most powerful man in the world really cares about keeping his hair. As does the richest man in the world, Elon Musk.
Besides celebrities, we often hear about athletes who get banned from competitions for using Propecia. The reason for this is because Propecia apparently masks the usage of other more serious banned performance enhancing drugs. Edit: Finasteride no longer banned for athletes since 2009 per Wikipedia.
However, you never ever hear of any major celebrity or athlete admitting to taking oral Avodart (Dutasteride) to tackle his or her hair loss. Notwithstanding Rick Rosner. Perhaps this is because most US doctors tend to prescribe Propecia and oral Minoxidil right away, since both are approved to treat hair loss?
Note that topical Dutasteride and topical Finasteride are also becoming very popular option to treat hair loss. As are scalp injections (mesotherapy) of both drugs.
Ashton Kutcher used Avodart for his Hair Loss
Ashton Kutcher with long hair.
This past week, well known actor Ashton Kutcher admitted that he used Avodart for 10 years to tackle his hair loss. I was amazed to read that statement. He might very well be the first ever world renowned celebrity to admit to taking this drug for hair loss. Moreover, he took it for a pretty long time, and seems to have had no major side effects.
Some key points from the interview and my thoughts:
Mr. Kutcher says that he took “the Avodart” from the age of 25-35 and stopped five years ago. He is currently 40 years old. So he took the drug from around early 2003 till early 2013. Avodart was only approved by the US FDA to treat enlarged prostates in November 2001. And it was probably not easily available off-label for treating hair loss in 2002. So Mr. Kutcher did a great job doing his research and getting a hold of the drug in early 2003. I wonder if he was on any hair loss forum in 2002, when the release of this miracle new hair loss drug caused insane levels of excitement?
Mr. Kutcher’s two children are currently 3 years old and 14 months old. So he had them both after quitting Avodart. Perhaps that was the reason he originally quit the drug? It is recommended that pregnant women not even handle Avodart. Moreover, many men taking Avodart stop taking the drug when trying to become fathers due to fears that it could lead to some changes in their sperm quality and potential birth defects in their children. However, there are no warnings on Dutasteride bottle labels in relation to men. There are, however, clear warnings for both women and for children regarding never handling the capsules.
I am curious how Mr. Kutcher got his hands on Avodart in 2003. Did he buy it online, or was there any American doctor who was willing to prescribe it to him for the off-label hair loss use?
Mr. Kutcher claims that he quit Avodart five years ago, did good for a year, but is now his hair again. In his own words: “And I think like, five years ago I stopped and I did really good for a year, and now it’s thinning out”. The half life of Avodart is around five weeks, so it does seem strange that he was not losing any substantial hair for a year after quitting the drug. And then losing it very slowly over the next four years, prior to a recent acceleration.
In any event, even if Mr. Kutcher’s time frames are a bit off or confusing, it is wonderful to get a data point regarding Avodart from a well known celebrity. The majority of hair loss forum members who try Avodart never seem to continue to take it for a decade.
Update June 5, 2018
Yesterday, Ashton Kutcher appeared on Conan and discussed his past 10-year usage of Avodart to maintain his hair, prior to quitting several years ago. The video was officially published today and is embedded further below. I was impressed by Mr. Kutcher’s knowledge that a testosterone byproduct (DHT) rather than testosterone itself is the root cause of hair loss. He seems like a true hair geek, although later on he fumbles a bit when he agrees with Conan that less testosterone = usually more hair.
Dihydrotestosterone (DHT) levels and your scalp hair’s genetic sensitivity to the ravaging effects of DHT are together what cause male pattern hair loss. Men with somewhat low testosterone levels can still have sufficiently high enough levels of DHT to end up going completely bald. And men with high testosterone levels can still not go bald at all if their follicles are not genetically susceptible to the attacks from DHT.
In any case, to the best of my knowledge, no major celebrity has ever admitted to using Dutasteride for hair loss in the past. Many have admitted to using the comparatively weaker drug Finasteride. What makes this admission from Mr. Kutcher even more striking is the fact that Dutasteride is not yet officially approved to treat hair loss in the US. Although tens of thousands of people have surreptitiously been using the drug for that purpose for over 15 years now.
