How Does Dutasteride Impact Testosterone and Estrogen Levels?

In 2015, I wrote a popular post on how finasteride impacts testosterone and estrogen levels. This time, I want to examine how  the stronger DHT inhibitor dutasteride effects testosterone and estrogen levels.

Propecia (brand name finasteride) increased mean circulating levels of both testosterone and estradiol (estrogen) by approximately 15% per one study by its manufacturer Merck. See page 8 in here for more details. However, this increase is not substantial enough to cause testosterone and estrogen levels to exceed the reference range. In the same study, finasteride (1 mg) rapidly reduced serum DHT by 65% within 24 hours of ingestion.

Dutasteride, Testosterone and Estrogen

Dihydrotestosterone (DHT) blockers reduce the conversion of testosterone to dihydrotestosterone. This results in higher levels of circulating free testosterone (aka the male sex hormone).

When first researching this subject a few years ago, I expected that dutasteride would cause significantly greater increases in testosterone and estrogen levels in comparison to the weaker finasteride. See my post on dutasteride being more effective than finasteride when it comes to hair growth. Note that the former also causes higher rates of side effects in comparison to the latter.

Dutasteride inhibits DHT levels to a far greater extent than finasteride. Moreover, it inhibits both type 1 and type 2, 5α-reductase isoenzymes which are responsible for the conversion of testosterone to DHT.

I take dutasteride (0.5 mg once every 3 days), and feel like it might have given me some weight gain and gynecomastia. However, the one time I measured my estrogen (female sex hormone) level, it was within the normal range for a male. I also have a far more sedentary life than when I used to be extremely skinny (although my caloric intake has not changed). On a side note, estrogen can lead to increased hair growth.

According to the package insert from GSK (the manufacturer of Avodart brand dutasteride):

“In BPH patients treated with 0.5 mg of dutasteride daily the median decrease in DHT was 94% at 1 year and 93% at 2 years. The median increase in serum testosterone was 19% at both 1 and 2 years. This is an expected consequence of 5α-reductase inhibition and did not result in any known adverse events.”

According to the Avodart monograph from GSK, a 52 week treatment with dutasteride 0.5 mg/day resulted in:

No clinically significant change compared with placebo in sex hormone binding globulin, estradiol, luteinizing hormone, follicle-stimulating hormone, thyroxine (free T4), and dehydroepiandrosterone. Statistically significant mean increases compared with placebo were observed for total testosterone at 8 weeks and thyroid-stimulating hormone (TSH) at 52 weeks. The median percentage changes from baseline within the dutasteride group were 17.9% for testosterone at 8 weeks and 12.4% for TSH at 52 weeks.”

Dutasteride Testosterone
Dutasteride and testosterone increase. Source: American Journal of Men’s Health, Volume: 11, Issue: 1. Favaro et al.

The good news is that after stopping dutasteride for 24 weeks, the mean levels of testosterone and TSH returned to baseline. However, note that this study consisted of a very small sample size of just 26 volunteers. The FDA drug facts page on Avodart has the same information.

When it comes to testosterone, other studies also seem to indicate similar changes. For example, a 2010 South Korean study of 120 patients with benign prostatic hyperplasia (BPH) found that dutasteride increased serum testosterone levels around 15-16 percent after one year of treatment. A 2018 Japanese study concluded a 20 percent increase in both total and free testosterone levels.

Conflicting Reports on Estrogen Changes

Dutasteride Estrogen
Dutasteride caused a slight increase in serum estradiol (estrogen) levels. Source: American Journal of Men’s Health, Volume: 11, Issue: 1. Favaro et al.

I find it hard to believe that finasteride can raise mean estrogen (or estradiol) levels by 15 percent, but the stronger dutasteride has a negligible impact. I will update this post as I find more studies discussing the impact of the latter on estrogen levels in men. One study from Brazil (image on right) concluded that:

“There were no statistically significant alterations in the serum estradiol levels in the dutasteride group compared with the placebo group. But there was a slight increase in the serum estradiol levels in the dutasteride patients.”

A more recent 2020 study from Japan concluded that dutasteride increased estrogen levels by 9.4%. However, the results of this study were strange due to the fact that DHT levels only declined by around 40 percent rather than the expected 90 percent.

ISHRS 2022 Hair Transplant Statistics

The International Society of Hair Restoration Surgery (ISHRS) publishes its practice census results every two years. I covered the 2020 one with worldwide hair transplant statistics in detail. Now its time for an update due to the release of 2022 data.

ISHRS 2022 Census Results

In April 2022, the ISHRS published its latest Practice Census results (covering 2021 data). It sent out the survey to its 858 Physician members, but only 197 replied back in time. Nevertheless, still some very useful findings. It seems like ISHRS membership declined from 929 to 858 during the past two years.

After extrapolations, the ISHRS estimated that 703,183 hair restoration procedures were performed worldwide in 2021. I always assume that the real number is much higher after including back-alley and unregistered hair transplants abroad in countries such as Turkey and India. The vast majority of hair transplants in the world are not performed by ISHRS members. In most countries, doctors and plastic surgeons often perform a few hair transplants every month as a “side gig” to their main practice.

Among the most interesting findings is that hair transplant surgeons are increasingly performing just one procedure per patient. Just a few years ago, it was common to perform 3 small procedures per patient.

Larger hair transplant megasessions of 3,000 to 5,000 grafts are now extremely common. Some surgeons are even performing gigasessions on rare occasions. Of course most patients will likely still need a second procedure in 10 plus years as their hair loss progresses.

Another important (but not surprising) finding is that Zoom and other methods of video communication have made people much more self-conscious about their hair loss. The so-called “Zoom effect”. I am glad that at my current workplace, no-one turns on their videos during Microsoft Teams calls.

The ISHRS hair restoration trends infographic has more interesting findings. I covered hair transplant surgery statistics in detail when the last 2020 census came out (keep scrolling for original post). This time, I only want to focus on this one table:

Hair Loss Treatment Survey
ISHRS Hair Loss Treatment Survey 2022.

From the above table and earlier infographic, I find the most interesting developments to be:

  • The percent of surgeons always or often prescribing oral minoxidil to treat hair loss rose from 10% in 2019 to 26% in 2021.
  • The percent of surgeons always or often prescribing dutasteride to treat hair loss rose from 6% in 2019 to 12% in 2021.
  • Almost one-half of all ISHRS members often recommend PRP for hair growth. This is surprising, but perhaps PRP does work at least modestly in most people. Even if just imperceptible to the naked eye hair follicle thickening.

July 4th, 2020

Hair Transplant Statistics 2020

ISHRS – International Society of Hair Restoration Surgery

Recently, the International Society of Hair Restoration Surgery published its 2020 census results. There are some very interesting hair transplant related findings presented in the summary.

However, the most interesting findings to me are those unrelated to hair transplants. Scroll through the end of this post to read about all the details.

The previous ISHRS census came out in 2017.

Future Treatments

My favorite question is on page 25: “What do you think will be the next technological “leap” in hair restoration?”

Out of 929 surgeons who were e-mailed this survey, only 201 surgeons answered this question. Hair cloning and stem cell therapies were the most popular responses:

Future Technologies in Hair Restoration
Future Technologies in Hair Restoration. Source: ISHRS.

How Many Hair Transplants Each Year?

Only 270 hair transplant surgeon members responded in time to this main survey question. After extrapolation and adjusting for anomalies, the ISHRS estimated that 735,312 hair restorations procedures were performed worldwide in 2019. This number represents a 16 percent increase from 2016, when an estimated 635,189 hair transplant procedures were tallied globally.

World Hair Transplant Surgery Totals by Region, 2019

Hair Transplant Totals by Region
Hair transplant procedures performed by region in 2019. Total = 735,312. Source: ISHRS.

Data Accuracy

Whenever I see such survey results, I am always highly skeptical about the annual global hair transplant totals. Although the ISHRS has around 1000 members across 70 countries, there are  likely several thousand surgeons in developing countries who do not join this organization.

Many of these “missing” surgeons offer hair transplants as a side offering at their general cosmetic surgery and dermatological practice. And many hospitals have surgeons who perform hair transplants infrequently. e.g., during emergencies such as burning accidents or scalp injuries.

This under-representation is even more exaggerated when you consider the numerous sketchy “roadside” hair restoration clinics in many developing countries. Most of these assembly line type clinics would likely not even get ISHRS membership applications approved.

Moreover, many legitimate clinics and surgeons in poorer countries cannot afford to join the ISHRS and pay annual dues. And many probably do not deem it worth joining a US headquartered organization. Especially if most of their local clients do not care about certifications and international association memberships.

I would therefore not be surprised if the actual number of hair transplant procedures that take place worldwide is closer to 2 million or even higher. The ISHRS totals for vastly populated China and India are likely heavily underestimated. The cost of a hair transplant in these countries is a small fraction of that in the developed world.

Moreover, an increasing number of studies and articles suggest that rates of balding in China and India have gone up significantly in recent years. I think that there is also significant underestimation when it comes to places such as Turkey, UAE (Dubai) and Thailand. In fact, a number of online news articles from reputable sites suggest that 100,000 hair restoration procedures take place in Turkey alone every year.

However, before booking a flight, make sure to read my post on the dangers of getting a hair transplant abroad.

Other Hair Transplant Statistics

Among the other interesting hair transplant statistics and related findings in this census/survey include:

  • An 85 percent to 15 percent split in the male versus female share of the hair transplant clientele. Not surprising.
  • A 66 percent “FUE only” versus 30 percent “FUT (strip) only” procedure type performed division. Also not surprising to me. See my past post on FUE versus FUT. The vast majority of FUE procedures are performed by motorized techniques, usually without suction.
  • Robotic-assisted FUE represents only 5.3 percent of all FUE procedures performed in the world.
  • 99 percent of FUE surgeons used punches of less than 1 mm size. No-one used punches of less than 0.8 mm size.
  • When it comes to FUE donor sites: 92.5 percent included scalp hair; 7.5 percent included beard hair; and 2.4 percent included chest hair. Body hair transplants (BHT) are therefore still not very popular.
  • 57 percent of patients needed only 1 procedure to achieve their desired result. A bit surprising to me. However, my guess is that many of these satisfied customer will eventually come back for a second procedure after some years due to further hair loss.
  • 81 percent of patients have between 1000-3000 grafts transplanted during their first procedure.
  • 87 percent of patients were between the ages of 26 and 45.
  • Only 13.4 percent of hair transplant surgeons’ patients came from a different country.

Present Hair Loss Treatment Survey

Another great section also does not involve any hair transplant statistics.

On page 16, there is a table titled: “How Often Various Treatments Were Prescribed to Patients in 2019“. 204 surgeons responded to this question. Not surprisingly, Finasteride and Minoxidil were by far the most popular treatment recommendations.

These two are the only ever FDA approved medications to treat androgenetic alopecia (aka male pattern baldness). The Finasteride recommendation breakouts in the table were split into 1% and 5% doses; as well as a separate topical Finasteride category.

I was surprised by the following findings:

  • A higher than expected 10.2 percent of responding physicians stated that they “always or often” prescribed oral Minoxidil to treat hair loss. In my past post on oral Minoxidil, I mentioned how it was become increasingly popular in Australia and Thailand. I would be nervous about the side effects of taking such a medication to treat high blood pressure. Especially a potential increase in body hair. However, it seems like many hair loss sufferers are biting the bullet and hoping to get superior results to topical Minoxidil.
  • Only 5.9 percent of the doctors “always or often” prescribed Dutasteride to treat hair loss. Very low in my opinion. Almost all comparison studies show that Dutasteride is superior to Finasteride in treating hair loss. But the former also has greater rates of side effects. It seems like hair transplant surgeons are reluctant to prescribe Dutasteride off-label to treat pattern hair loss. Even natural DHT blocker Saw Palmetto was recommended as a hair loss treatment more frequently (8.5 percent) than Dutasteride.
  • Around 30 percent of patients were often recommended to take natural supplements, vitamins, herbs and Biotin. Nutritional deficiency related hair loss is not common, and is usually temporary in nature. So this number is higher than I would expect.

Hair loss treatment and cure related news updates.