Stanford urologist discusses risks of finasteride on Huberman Lab podcast

On November 6, Dr. Andrew Huberman spoke with Dr. Michael Eisenberg, a urologist and professor at Stanford Health Care in California. The episode, titled “Improving Male Sexual Health, Function & Fertility,” included a discussion of the risks of finasteride, including post-finasteride syndrome. The transcript has been lightly edited for readability.

DR. ANDREW HUBERMAN: As long as we’re talking about DHT, dihydrotestosterone, it’s only fair to discuss the drugs that many people take to suppress dihydrotestosterone in hopes to keep or grow their hair—things like finasteride, dutasteride. Some, maybe many, not all people who take these drugs, particularly in oral form, experience sexual dysfunction issues and other issues related to suppressing DHT. That said, my understanding is that these drugs are also quite useful, maybe even life-saving in some cases, for staving off certain forms of prostate cancer. What are your thoughts about finasteride, dutasteride: Do you see people coming into your clinic who are having sexual dysfunction or other types of issues because of their hair, or attempt to maintain or grow their hair?

Equally important is that we talk about so-called post finasteride syndrome. I get a lot of questions about post finasteride syndrome because, I’ll describe it in a couple of minutes, it sounds pretty devastating for these people’s lives. I’ll explain why it’s so devastating for them in a moment, but what about finasteride, dutasteride and these drugs that are effectively DHT blockers? DHT levels if they get too high indeed can miniaturize the hair follicle, cause people to lose their hair, typically up front or in the back, so-called crown or widow’s peak, or everywhere in some cases. It also induces hair growth on the back, beard growth as we understand, but then people go and take these drugs to try and maintain or grow their hair and often times they have erectile dysfunction or other issues. Is that surprising to you?

DR. MICHAEL EISENBERG: I think the men that we see these side effects in tend to be younger men in their 20s, 30s and 40s and they’ll take it, as you’re pointing out, for hair loss. Before it was FDA-approved for that indication, at least finasteride, they did randomized control trials to look, and one of the other things that we’ll talk about too is reproductive effects. So they did lots of studies to see if there were changes in semen quality for men on finasteride versus the placebo, and there were some very subtle changes.

But in postmarketing now [the period since finasteride was approved in 1997], we see these patients in clinic. Everybody enrolled in [the clinical trials] had normal function, so I think that’s important to understand. Obviously that’s not life, right? People come in with different baselines and different amounts of reserve. We now know that there’s probably people that are a lot more sensitive to these medications than others. There are some men that drop their sperm counts dramatically, and usually if we stop these medications their sperm counts can recover. A spermatogenic cycle is probably about 2 to 3 months, so usually in maybe 3 to 6 months we usually see recovery for most men.

But similarly for sexual function, I certainly have a number of patients that do complain of low libido, erectile function, this post-finasteride syndrome. The mechanisms I think are less certain because measuring testosterone levels—which we do sometimes if androgens are low or even if androgens seem to be in the normal range or low-normal range—we’ll try and increase testosterone through a variety of means: testosterone, clomiphene sometimes. It helps some men but not all, so I think the exact mechanism of what is going on here, what is changing: we need more understanding about the exact pathophysiology, neurochemically.

HUBERMAN: It seems like a pretty serious trade-off, to either maintain to grow hair, or lose sexual function. I talked about DHT and some of these side effects or finasteride on previous episodes. I’m not a clinician, but my encouragement is always for people to approach these drugs with a real level of seriousness, if not caution. The post-finasteride syndrome was described in these online questions as seemingly permanent, even though people had ceased to take finasteride or dutasteride. So in other words, they were taking this stuff, I don’t know how they felt while they were on it, but they stopped taking it and the sexual dysfunction issues don’t seem to be resolving. Does that mean they should go see you or another male urologist, reproductive health specialist?

EISENBERG: Oftentimes they do for these complaints. They start to notice it when they’re on the medication, then when they, usually through online research, learn about this potential entity, sometimes they discontinue. Some men do have resolution when they stop, but there is this permanence in some handful of men. They’ve done MRI imaging to try and understand more anatomically or functionally what exactly is going on. I think there’s still a lot of unknowns about it, but it can be permanent for some. So they come in and they see me in clinic—erectile dysfunction, low libido—and then we go down all the host of treatments that we talked about and the evaluations that we talked about. Again, we have resolution in some, but there are some that seem treatment refractory [i.e., do not respond to treatment].

Yikes, that’s my only response. Permanent effects on sexual health as a consequence of an attempt to maintain one’s hair: it sounds like something that people need to think very seriously about.

Dr. Andrew Huberman

HUBERMAN: Yikes, that’s my only response. I mean, permanent effects on sexual health as a consequence of an attempt to maintain one’s hair. This is where, in all seriousness, it just sounds like something that people need to think very seriously about. Because as I understand there’s nothing that can predict whether or not someone will have post-finasteride syndrome, right?


HUBERMAN: I did a bit of reading on this within the scientific journals as well. There isn’t a lot of information as you point out because it’s a fairly recent phenomenon. That highlights a different issue: this may be the first time in history where young males are taking finasteride and dutasteride, and that might be the cause of the post-finasteride syndrome, right? I think you you alluded to this earlier. These drugs have proven to be very beneficial for older men treating prostate issues.

EISENBERG: Exactly, yeah.

HUBERMAN: So post finasteride syndrome, I think, falls under the category of medical conditions that, a few years ago we would hear the same about chronic fatigue syndrome. Even fibromyalgia, not long ago was considered one of these “oh is it all a psychosomatic issue?” We now clearly know that’s not the case for fibromyalgia by the way. But I can recall a time not that long ago when people in the medical profession were kind of like “well yeah, I don’t know if this is a real thing,” but post-finasteride syndrome sounds certainly real for the people that are suffering from it.

EISENBERG: Exactly, yeah.

HUBERMAN: Well the reason I’m spending so much time on this is that I get a lot of questions about it, and there are clearly a lot of young males who take finasteride or dutasteride, or are thinking of doing that for cosmetic reasons, and I think they should be aware of the potentially serious consequences.

EISENBERG: Yeah, agree.

Learn more about the risks of finasteride.