Physicians & researchers expressing concerns about adverse effects of finasteride

Following are excerpts of articles, videos and tweets of doctors expressing concerns about harms of finasteride. (There are other doctors who consider the drug “safe and well-tolerated.”)

Letter & comments

Ophthalmologist in the San Francisco Bay Area (US)

I am writing to increase awareness regarding finasteride, a medication with several under-recognized and under-reported adverse effects.

Patients and doctors remain largely unaware of the long term consequences of this drug on the nervous system and mental health. Unfortunately, some of the side effects of finasteride are more serious and persistent than the original condition it is intended to treat. Neurotoxicity is likely more common than reports would suggest.

In my San Jose, California ophthalmology clinic, we encountered a surprising association between finasteride use and presence of optic neuropathy or retinopathy…

It is especially important that physicians recognize the potential for this drug to impact optic nerve function. This is a medication that patients may conceal or leave off their lists of medications since it is marketed separately via the internet directly to patients. We have made it a point now to ask every patient about finasteride use.

Excerpt from: Keshav Narain, MD. A Letter regarding Finasteride. Website of South Bay Retina, an ophthalmology clinic.

Sexual medicine specialist in San Diego, CA (US)

5-alpha reductase is not only used to convert testosterone to dihydrotestosterone. 5-alpha reductase converts androstenedione to dihydroandrostenedione; progesterone to dihydroprogesterone; [and several other neurosteroid conversions]. Every one of those events is blocked by finasteride. Every one of these agents goes to make neurosteroids that are participating in the patient’s thinking, decision-making, executive function. We are voluntarily making people block all these things with the hope that they’re going to shrink their prostate or grow some hair. It’s ridiculous.

With Hims and Keeps and Roman, the number of patients getting on these crazy drugs is exponentially increasing, despite all the evidence and all the discussions. There are dozens of PFS articles out now. The statement that “Oh this doesn’t really exist,” that’s just nonsense.

Dr. Irwin Goldstein, Director of San Diego Sexual Medicine, in the Q&A portion of a webinar held by the Sexual Medicine Society of North America (SMSNA) on 27 Jul 2021. Webinar description | Full video (link goes to Goldstein comment at 54:33)

Emeritus professor of medicine and medical safety expert in Israel

We have to start listening seriously to patients. It took two decades to understand the severe dangers from Propecia, with the help of reporting and monitoring.

Mayer Brezis, MD, Emeritus Professor of Medicine, Hebrew University Hadassah Medical School. Quoted in article in Haaretz newspaper

Lifestyle recommendations from Cornell male fertility center

Do not use finasteride (Propecia, Proscar) for hair loss. There is accumulating evidence that it negatively impacts male fertility…

Men’s Health and Fertility Lifestyle Information, Weill Cornell Center for Male Reproductive Medicine & Microsurgery. Director: Marc Goldstein, MD

Physician and director of a fertility clinic in Israel

I treated several cases of couples who already had a child or two trying over the course of a year or two to become pregnant again, but without success. And then I examine both partners, send the man for a sperm test, and a significantly abnormal test result comes back – a low sperm count that requires IVF because the chance of a natural pregnancy is too low. And then you ask what he is taking, and it turns out he is taking Propecia.

Dr. Shahar Kol, director of the in-vitro fertilization unit at Elisha Hospital, Haifa, Israel, quoted in article in Haaretz newspaper

Professor of neurobiology at Stanford School of Medicine [not a physician]

[Finasteride] can reduce DHT levels, certainly, more for those that are sensitive to it… DHT is powerful in development, and it’s powerful throughout the lifespan. And so, you want to keep levels of DHT appropriately high.

Dr. Andrew Huberman, Associate Professor of Neurobiology, Stanford University School of Medicine, on The Tim Ferriss Show, episode 521

(In April 2023, Dr. Huberman discussed post-finasteride syndrome on his podcast. Read the transcript)


Videos

Dr. Alexander Pastuszak, MD, PhD, 2019
Dr. Maria Uloko, 2021
Dr. Michael Irwig, 2011
Prof. Hartmut Porst, 2021

Tweets