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  Federal ICE special agent ravaged by Propecia, stripped of badge and gun, calls for Merck CEO to come clean on hair loss drug's devastation side effects.




Dr. Michael Irwig at George Washington University has published a new study on depressive symptoms and suicidal thoughts in former users of Finasteride with persistent sexual side effects.

Selected excerpts:

  • Pharmacovigilance is the science relating to identifying, monitoring, and effectively reducing adverse drug reactions. When a drug comes to market, it is often studied in only a thousand patients or less, as in the case of finasteride. 1,2 Less common adverse effects of a medication may be uncovered only in the postmarketing phase after many thousands of patients have been exposed to the medication.3
  • In April 2012, the US Food and Drug Administration announced changes to the professional labels for Propecia (finasteride 1 mg) to expand the list of persistent sexual adverse events reported.8 ... In December 2010, the product labeling for Propecia in the United States was updated to include the side effect of depression.13
  • In a group of 61 otherwise healthy former users of finasteride who developed persistent sexual side effects, depressive symptoms were present and categorized as mild in 11% of users, moderate in 28% of users, and severe in 36% of users. Suicidal thoughts were present in 39% of former finasteride users, and an additional 5% chose the statement “I would like to kill myself.
  • The corresponding rates of depressive symptoms and suicidal thoughts were significantly lower in a control group of young men with male pattern hair loss who had not used finasteride and who did not have any current or past psychiatric conditions or use of psychiatric medications.
  • A plausible biological mechanism to explain the association between finasteride and depression lies with neuroactive steroids, neuromodulators that are synthesized in the central nervous system itself and that are also transported to the brain from the gonads and adrenal glands.
  • It turns out that finasteride crosses the blood-brain barrier and blocks the enzyme 5α-reductase, which reduces the concentrations of multiple neuroactive steroids derived not only from testosterone, but also from progesterone and deoxycorticosterone.... reduced concentrations of neuroactive steroids are associated with depression in several human studies.
  • Although the effects of finasteride in the human brain are poorly understood, clinicians, as well as potential finasteride users, should be aware of the serious potential risks of this medication, especially as it is being used cosmetically to alter a normal age-related process. This is the first study to document suicidal thoughts in (former) users of finasteride.

Journal of Sexual Medicine



Dr. Abdul Traish (PhD, MBA in the Department of Urology at Boston University School of Medicine) has published a new paper on the importance of 5-alpha reductase type 1, 5AR type 2 and the newly discovered 5AR type 3 enzyme, and the effects of 5AR inhibitors such as Finasteride (Propecia, Proscar) and Dutasteride (Avodart) on these enzymes and bodily processes.

Selected excerpts:

  • 5α-reductases are a family of isozymes that play a critical role in transformation not only of testosterone but also of progesterone, DOC, aldosterone and cortisol into a host of neuro-active steroids that regulate multitude of functions in human physiology.... the neuro-active steroid hormones modulate multitude of functions in human physiology encompassing regulation of sexual differentiation, neuro-protection, memory enhancement, anxiety, sleep and stress, among others.
  • While the clinical use of 5α-reductases inhibitors was well established, the scope and the magnitude of the adverse side effects of such drugs especially on the central nervous systems is still unrecognized, due to lack of knowledge of the various physiological function of this family of enzymes, especially in the central nervous system.
  • There is an urgent need to better understand the function of 5α-reductases and the role of neuro-active steroids in human physiology in order to minimize the potential adverse side effects of inhibitors targeting 5α-reductases to treat BPH and AGA.
  • Until recently, the adverse effects of 5α -reductase inhibitor therapy were thought to be very minor and well tolerated (80, 81, 82). However, new information suggests that these drugs may impair sexual function including sexual desire, erectile and orgasmic function [Table 3](for review cf. 83, 84). Recent studies in animal models suggested that these agents alter penile tissue histo-architecture and nitric oxide synthase function in penile tissue and thus can contribute to erectile dysfunction (85, 86, 87).
  • It is particularly important to note that in a subset of patients, the effects of these drugs are long lasting and may be irreversible (84). An association between use of these inhibitors and depression is also noted (88), suggesting potential adverse effect on the brain.
  • A number of case reports have suggested that 5α-reductase inhibitors therapy is associated with angioedema ( 91); cataract and intraoperative floppy-iris syndrome (92), pseudoporphyria, (93),T cell–mediated acute localized exanthematous pustulosis (94) and gyncomastia and male breast cancer (28, 95).
  • The recent introduced warnings on the drug labeling also suggests that increased awareness of the potential irreversible side effects of these agents [FDA].

Journal of Sexual Medicine


Dr. Michael Irwig at George Washington University has published a new study on persistent Finasteride side effects
. This new 2012 study is a follow-up to his March 2011 study titled "Persistent Sexual Side Effects of Finasteride for Male Pattern Hair Loss".

Selected excerpts:

  • "In a group of 54 otherwise healthy former users of finasteride who developed persistent sexual side effects that lasted for at least 3 months, 96% continued to experience these effects when reassessed 9–16 months (mean 14 months) later, raising the possibility of permanent effects."

  • "There is a solid and growing body of basic science evidence that finasteride reduces the concentrations of several neuroactive steroids that play a role in neurogenesis and neuronal survival."

  • "To explain the long-term neurological effects of finasteride, it is possible that reduced concentrations of neuroactive steroids are affecting the plasticity of neuronal architecture in regions of the brain responsible for sexual function."

  • "Another recently published study found that rats treated with finasteride for 4 weeks had a 26% reduction in the weight of their corpora cavernosa as compared with a control group [27]. This finding is consistent with the reports of genital shrinkage reported by some of the human subjects in this study."

  • "The most volunteered changes related to the urogenital system in terms of semen quality and decreased ejaculate volume, reduction in penis size, penile curvature or reduced sensation, fewer spontaneous erections, decreased testicular size, testicular pain, and prostatitis. Many subjects also noted changes to their mental abilities, sleeping patterns, and/or depressive symptoms. Many subjects reported a “disconnection” between the mental and physical aspects of sexual function."

  • "The typical story of men with persistent sexual and other side effects is that they unsuccessfully seek help from various providers in multiple medical specialties. It is important for physicians to acknowledge with their patients the current limitations in medical knowledge, particularly as it relates to neuroscience. There is no known blood or imaging test to study or measure neuroactive steroids or their metabolites in different areas of the brain associated with sexual function."

  • "Further valuable research could determine who would be susceptible to finasteride through genetic studies of polymorphisms of 5a reductase and the androgen receptor. Further research with validated instruments is needed to study the nonsexual persistent side effects associated with finasteride."


ABC News: July 12, 2012
For Some Men, Propecia's Sexual Side Effects May Be Long-lasting
Kevin Malley was almost 30, and he was starting to lose his hair. He went to his doctor to see if there was a way to keep from going bald, and his doctor prescribed Propecia. "I looked young for my age, so I wanted to hold off my hair loss for a little bit," Malley said. "I didn't plan on taking Propecia for more than a year." Malley started taking the drug in May 2011, and by October he was completely impotent and had no sex drive whatsoever. His body changed, even his genitals shrank, and he slipped into a mental fog that he just couldn't clear. His doctor told him the side effects would go away if he stopped taking the drug, so he did. But nothing changed.
Time Magazine: July 12, 2012
Propecia Problems: Baldness Drug Linked with Long-Lasting Sexual Side Effects

In April, the Food and Drug Administration (FDA) updated the warning to finasteride, Merck & Co.’s drug marketed to treat both male pattern baldness (Propecia) and enlarged prostate (Proscar). The new warnings noted that the sexual side effects associated with the medication, including problems with libido, ejaculations and orgasm, could last even after patients stop taking the drug. Now a new study published in the Journal of Sexual Medicine finds that side effects may not only continue after stopping finasteride, but they may last for months or even years...
MailOnline: July 12, 2012
Baldness Drug Wayne Rooney Took 'Could Cause Permanent Impotence and Shrink Genitals in Some Men'
Men taking medication for hair loss may suffer from prolonged and possibly irreversible impotence, according to scientists. The recent findings come after one patient bravely stepped forward to reveal the drug left him with no sex drive and even shrank his genitals. Kevin Malley, 30, was prescribed with the drug Propecia after he worried he could be losing his hair. He said he only planned to take the pill for a year...
The Sun: July 12, 2012
Hair Loss Drug Used by Rooney 'Could Cause Impotence'

The hair-loss drug used by Wayne Rooney to restore his barnet could cause IMPOTENCE, a scientist has warned. Roo took the drug Propecia back in 2009, and has since had a hair transplant to fight back against his receding hairline.  But research suggests that one of the ingredients in the medication – finasteride – can cause persistent sexual problems, including low sexual desire, erectile dysfunction and problems with orgasms...



Credit: Lexis-Nexis

Exceprts from the article:

  • "When the Food and Drug Administration approved the hair-growth drug Propecia in 1997a number of doctors and medical researchers voiced their strong concerns about the drug’s severe side effects. One outspoken critic was well-known hair-restoration expert L. Lee Bosley who publicly denounced Propecia as a "serious health concern" in the wake of its FDA approval—only to allow his doctors to enthusiastically recommend the medication to patients a few years later.

  • On Dec. 24, 1997, Bosley Medical—which bills itself as "The World's Most Experienced Hair Restoration Experts" and today boasts some 70 offices in the U.S., Canada, Mexico and China—issued a news release via paid-distribution service Business Wire. Headlined "Supposed Miracle Baldness Cure Creates Serious Health Concerns Among Hair Restoration Professionals," that release (still housed on LexisNexis) quoted Dr. Bosley as saying of Propecia:

    "The FDA has just approved a drug that has the capability to impair male sexual performance, creating the inability to achieve an erection [and] decreases libido... The potential side effects, especially the long-term side effects of the drug, should be the overriding concerns to both the users and the manufacturer."

  • Dr. Bosley also said of Propecia (generic name: finasteride) that "the results attained during the clinical trials would immediately be dismissed as unacceptable by our standards." All of which is enormously ironic, say Bosley patients, particularly the assertion about Propecia being unacceptable by the standards of Dr. Bosley. For as shortly as three years after Dr. Bosley issued his stern warning of Propecia, Bosley Medical doctors began prescribing the risky drug.

  • Within a few months of starting on Propecia, [Julian] Parks says he developed excruciating pain in one testicle, which lasted two years.  A few years later, while still on the drug—though at half-dose—he says he developed Peyronie's disease, a painful disorder characterized by the growth of fibrous scar tissue inside the penis, which often causes curvature of the erect organ. Parks, who says he previously had no major health concerns, finally quit the drug in 2006 after suffering other side effects. To this day, most of them have yet to resolve themselves.

  • Seven weeks after starting on finasteride, the previously healthy [Thomas] Schultz says he became extremely depressed and was beset by panic attacks. That while witnessing his genitals shrink to tiny proportions and grow completely numb. And though he quit the drug two weeks later, Schultz says his health rapidly worsened.

    Among his side effects—which continue to afflict him to this day—have been loss of libido, impotence, breast enlargement, prostate pain, muscle aches, cognitive dysfunction, anhedonia and severe insomnia, as well as Peyronie's disease. Meanwhile, Schultz says he has consulted some of L.A.'s top urologists, neurologists and endocrinologists, all of whom have told him there's nothing they can do to help. When Schultz discovered that Dr. Bosley had issued a press release in 1997 warning of Propecia's dangers, he said, "I grew sick to my stomach at his betrayal of innocent, unsuspecting people like myself."

  • Known clinically as Post-Finasteride Syndrome, the condition that has ravaged Shultz, Parks and thousands like them around the globe is marked by sexual, neurological, hormonal and physical side effects—including impotence, Peyronie's disease, testosterone deficiency and depression—that do not resolve themselves after quitting Propecia."




Cardiologist Rosemary McGeady, mother of Propecia
suicide victim
joins Kevin Malley's Merck protest.

ER-physician John Santmann, father of Propecia suicide victim Randy Santmann, joins to support Kevin's Malley's hunger-strike protest at drug-maker Merck's headquarters.


John Santmann (center) attends demonstration outside Merck headquarters in Whitehouse Station on Monday.
His son killed himself in 2008 after experiencing side effects he believed were from the drug Propecia.
Photo Courtesy of Kevin Malley


Protester Suffering Erectile Dysfunction, Career Loss, Breakup with Fiancee


Kevin Malley is on a hunger strike outside Merck headquarters
Photo credit: Kevin Malley


A 30-year-old Las Vegas man whose life was devastated by Propecia has launched a hunger strike at Merck & Co.'s corporate headquarters,
in protest of the pharmaceutical giant's failure to acknowledge the hair-loss drug's role in causing a battery of persistent side effects, including sexual dysfunction.

Kevin Malley, a former public-health researcher from Las Vegas, who flew to New Jersey from his hometown on May 10, ceased eating on May 13 at 3 p.m., and plans to continue going without food indefinitely while camped across from One Merck Drive.

"I want Merck to see how their drug is destroying lives—and know that I'm just one of thousands of victims suffering across the globe," said Malley, who was prescribed Propecia last year by his doctor, and took the controversial medication for five months until suffering complete erectile dysfunction and loss of libido last winter.

"Even now, eight months after quitting Propecia, my sexual dysfunction has not resolved itself," added Malley. "I also suffered severe memory loss and disorientation, which made it nearly impossible to concentrate on my work."

As a result of his physical and psychological ailments, Malley resigned from his research position late last year. He has since taken a job as a waiter at a Las Vegas restaurant to make ends meet.

Meanwhile, he and his fiancee broke off their engagement when she learned that his sexual side effects appear to be permanent. And while trying to come to grips with his condition, Malley came across, a support group for men suffering from persistent finasteride side effects. There, he encountered many other men suffering similar fates long after quitting the drug.

Malley has reported his case to the Food and Drug Administration via its MedWatch program. And in January he called Merck's Adverse Reporting hotline (800-444-2080), but the company, which enjoys annual Propecia sales of more than $440 million, told him, "We don't have any answers for you right now," he said.

Known clinically as "Post-Finasteride Syndrome" (and so called for Propecia's generic name, finasteride), the condition is marked by sexual, neurological, hormonal and physical side effects—including impotence, Peyronie's disease, testosterone deficiency and depression—that do not resolve themselves after quitting Propecia, and may be irreversible.

On April 11, the Food and Drug Administration ordered Merck to revise the labeling on Propecia to reflect mounting evidence that the medication can cause continued sexual dysfunction long after patients have stopped taking it. Of the 421 Propecia-related sexual dysfunction cases the FDA reviewed in its probe, 14 percent lasted longer than three months after patients discontinued the drug.

On April 20, according to a report in The Examiner, the FDA began widening its probe into Propecia, stating that the agency "will continue to vigilantly evaluate and analyze all reports that are available on finasteride and take regulatory actions as warranted."

The FDA has also been actively encouraging victims to submit reports about "all adverse reactions potentially caused by finasteride [including] cases of patients who developed Peyronie’s [disease], anxiety, panic attacks, cognitive dysfunction, chronic insomnia, muscle wasting and other persistent side effects."




The FDA has mandated that Finasteride (Propecia, Proscar) must carry additional warnings regarding the possibility of persistent sexual side effects.


Selected Excerpts:

  • A revision to the Propecia label to include libido disorders, ejaculation disorders, and orgasm disorders that continued after discontinuation of the drug.

  • A revision to the Proscar label to include decreased libido that continued after discontinuation of the drug.

  • A revision to both the Propecia and Proscar labels to include a description of reports of male infertility and/or poor semen quality that normalized or improved after drug discontinuation.




France's TF1 news station broadcast a report on persistent Propecia side effects, dangers of the drug, medical and health regulatory agency opinions, and interviews with men suffering from Post-Finasteride Syndrome -- persistent sexual, physical & neurological side effects that did not resolve after stopping Finasteride.






Following recent warnings & label changes from the FDA in the U.S., Health Canada has issued an alert that both Finasteride & Dutasteride may increase the risk of high-grade prostate cancer. Labeling has been updated for both drugs as a result.

  • "Health Canada is informing health professionals and the public that the prescription drugs finasteride and dutasteride may be associated with an increased risk of developing a serious form of prostate cancer known as high-grade prostate cancer. High-grade prostate cancer is an aggressive type of prostate cancer that grows and spreads more quickly than low-grade prostate cancer."
  • "The Canadian labels for the brand name drugs have been updated to inform about the increased risk of high-grade prostate cancer associated with these drugs and to emphasize that these drugs are not approved for the prevention of prostate cancer. Updates to the generics will follow."




Columnist John Peige of the Baltimore Courts Examiner continues to write about the issue of persistent Finasteride side effects, the FDA's safety review of Propecia, and new FDA-mandated labeling changes for the drug.



Columnist John Peige of the Baltimore Courts Examiner has written a scathing report on the issue of persistent Finasteride side effects, the medical community's lack of awareness of the problem, class action lawsuits, and the need for more research to find a cure.



Selected excerpts:

  • Doctors at two of this country’s leading medical schools have linked the hair growth drug Propecia to prolonged and possibly irreversible male sexual dysfunction, clinical depression, breast cancer and high-grade prostate cancer.

  • The drug was approved by the FDA in 1997 to promote hair growth in men suffering from male pattern baldness. As devastating as these revelations are, millions of men who have been prescribed the drug Propecia have no idea that they may be at risk. Even worse, many doctors continue to prescribe Propecia unaware of the drug’s shocking side effects.

  • Many men have undergone costly and time-consuming medical tests and treatments that will not detect or treat the source of the problem. They are told there is no problem. “In fact, patients have been told to see psychiatrists and psychologists because the problems were in their head,” says Dr. Irwig.

  • While labeling on the medication in the U.S. recently warned about reported cases of persistent erectile dysfunction, there is no reference to the other sexual side effects being persistent. Other countries, including the United Kingdom and Sweden, several years ago documented persistent risks and required the drug’s maker to include them in labeling. It is not known exactly what causes these side effects.

  • What is known is that unlike the vast majority of drugs, whose side effects cease when you stop taking them, Dr. Irwig explains that “finasteride is different because it can actually change the brain’s chemistry. The enzyme 5 alpha reductase is present in many areas of the brain. It is rare for a drug to have the capability to persistently change the brain's chemistry.

  • There is no known cure for men who have suffered from these severe symptoms that have destroyed their sexual function.

  • Diagnosing these maladies is further complicated by the fact that the doctors who are prescribing Propecia are typically dermatologists and general practitioners. The doctors who are treating the symptoms of Propecia’s side effects are typically urologists and endocrinologists. Because of their diverse disciplines, they rarely have any cross interactions.

  • The first class action lawsuits are now being filed. While individual lawsuits have been filed on the behalf of plaintiffs over the last several years, Dr. Irwig’s study and another recent review study on Propecia’s side effects in the Journal of Sexual Medicine by researchers at Boston University have now moved the discussion from an anecdotal one to one that has the credence of two of America’s most well-known medical schools.

  • Two weeks ago, class action suits were filed in California and Florida joining those already filed in other states. More lawsuits are expected to be filed shortly in other jurisdictions.




> Check newsstands for the December 2011 Men's Health issue (Ashton Kutcher cover, article on pg. 102-105).

> Read FULL article online [7 pages]:

Author Jim Thornton has written a Special Report on persistent Propecia side effects, the "Post-Finasteride Syndrome" and growing medical and legal awareness surrounding these issues.


Selected excerpts:

  • Charles decided to start taking Propecia, the only FDA-approved oral medication for male-pattern baldness. For the next 6 years he tolerated the drug fairly well. But he noticed one odd side effect: a random, intermittent decline in his sex drive. "I'd be with a sexy woman, and there was just no interest at all on my part," he recalls. "If anything, it was almost like I felt mild repulsion."

  • ... he [Mark J.] suffered what some doctors have come to describe as an "endocrine system crash." Old symptoms returned and were more severe than ever, accompanied by strange new ones: hot flashes, extreme fatigue, and visible changes to the structure of his penis and scrotum, both of which literally began shrinking overnight. His libido vanished entirely. "Forget the fact that I wasn't very horny anymore," he says. "Now there was just no urge for sex whatsoever. I could be with the hottest girl on the planet and nothing would happen, either down there or in my head. It was as if my brain could no longer respond to anything erotic—visual or through touch."

  • OVER A DOZEN PFS PATIENTS CONTACTED by Men's Health revealed remarkably similar symptoms to the ones described by Mark J. and Charles K. One man reported that since using and then quitting finasteride, he has been wandering through life in a state of constant "brain fog." Yet another views himself as an "asexual zombie."

  • "Before our study, the published research indicated these were largely reversible side effects," says lead researcher Michael Irwig, M.D., an endocrinologist at George Washington University. But in this select population, over 90 percent were suffering from low sexual desire, erectile dysfunction, and decreased arousal—this after being finasteride-free for 40 months on average. One man had still not improved 11 years after taking his final pill. "It's a real irony," says Dr. Irwig. "Men took finasteride to stop or prevent hair loss and sometimes to improve their dating lives. And it actually ended up destroying their sexuality and self-esteem."

  • In a 2011 study review in the Journal of Sexual Medicine, lead researcher Abdulmaged Traish, Ph.D., and his colleagues outlined extensive cause for concern. They concluded that animal and human studies strongly suggest that finasteride isn't limited to its target tissues but in fact can reduce DHT in many tissues, potentially affecting not only nerve-signaling pathways in the penis but also the ratio of male-to-female hormone levels circulating through a user's body. One study Traish cites found that men taking 1 milligram of finasteride daily had significantly higher levels of estradiol—the predominant female sex hormone—than men taking a placebo. Just as worrisome as the possible effects in body tissue is the growing evidence that finasteride can enter a man's brain and disrupt key chemicals therein.

    As Traish's study review details, once finasteride reaches brain tissue it affects the production of more hormones than just DHT. At particular risk, Traish believes, are neurosteroids—brain chemicals that play a role in reducing anxiety, enhancing memory, regrowing brain cells, and helping us sleep.

    There's yet another issue for men who already find themselves battling feelings of despair over their dissipated sex lives: At least two studies have shown that finasteride may cause the onset of depressive symptoms. And last year, researchers in Germany found that the drug inhibits the growth of new neurons in the brain's hippocampus ; this type of neurological "failure to thrive" has also been documented in people who suffer from clinical depression. 

    "The percentage of affected men may be small," acknowledges Traish, a researcher in the biochemistry and urology departments at Boston University's school of medicine, "but our research definitely concludes that PFS is real. For a subset of these men, the damage persistsmaybe forever—even after they go off the drug. We don't fully understand why, but it is as if something shuts off biologically, and stays that way."

  • To the surprise of virtually no one, anger over Merck's actions has bubbled its way into the legal system. At least two class-action lawsuits—one in the United States and one in Canadahave been filed on behalf of PFS patients seeking damages for the harm they say Propecia has caused them.

  • Among other problems, Mark still suffers from a lack of nocturnal erections, genital numbness, and dulled orgasm. His libido has flatlined altogether, along with his zest for life. His once-defined musculature has given way to breast enlargement, atrophied arms, and female-pattern fat distribution in his hips—"this," he says, "despite keeping the same diet and exercise levels I had before ever taking the drug." He has recently joined a class-action suit—not for personal gain, he says, but in the hope that continuing pressure will convince Merck to fund further research into PFS.

  • "What we do want," says Dr. Irwig, "is for patients and doctors alike to understand the potential risk of persistent problems that may not, in fact, be reversible when you stop this drug. Even if there's only one chance in 300 that it could happen to you, it's like playing with fire. If you're one of the 299 who don't have problems, that's great. But if you're the one who does, you're going to be kicking yourself for ever taking this medicine."



alexander-skarsgard-covers-mens-journal-october-2011In the October 2011 Men's Journal issue (Vol 20, #9, pg. 66-67), author Mickey Rapkin writes about the growing scrutiny regarding Propecia and hair loss drugs

Selected excerpts:

  • "Jeff O. was 35 when his wife first confronted him about their increasingly anemic sex life. The couple had gone from almost daily romps to something like once every two months. "I had barely noticed," Jeff says. "I could have an erection. But it wasn't nearly as hard as before. ... After multiple visits to the doctor and a battery of tests, Jeff learned he was suffering from low testosterone, and the likely cause shocked him. "I'll be on hormone therapy for the rest of my life," he says, "because of Propecia."

  • "Propecia was hailed as something of a miracle drug when it first hit the market in December 1997... at the time, pharmaceutical manufacturer Merck warned that a small percentage of all Propecia users could experience wilting erections and decreased libido. But to the millions of people who turned to Propecia to prevent hair loss, it was well worth the risk."

  • "Now, new research shows that Merck may have underestimated the persistence of some of Propecia's side effects.  ...If there's a smoking gun here, it might just be in Merck's own hand.  According to a complaint filed in Florida, Merck expanded the warning on the product label to include the "persistence of erectile dysfunction after discontinuation" in the face of a study by Sweden's Medical Products Agency suggesting that Propecia could be a long-term sexual inhibitor.  But the rewrite appeared just in Sweden. In March 2010 the fine print was also amended in Italy, but nothing about the possibility of lasting sexual side effects appeared in the U.S. until this spring..."


Dr. Irwin Goldstein, Editor-In-Chief of the Journal of Sexual Medicine, published a July 2011 editorial on the dangers of 5-alpha reductase inhibitors Finasteride and Dutasteride titled "An Old Problem with a New Cause—5 Alpha Reductase Inhibitors and Persistent Sexual Dysfunction"

Selected excerpts:

  • "...We are becoming more and more aware of persistent sexual health problems occurring as a result of the use of 5 alpha reductase inhibitors, finasteride, and dutasteride, in a subset of patients.   What is even more alarming is that in addition to persistent sexual issues, there are persistent central cognitive issues and concerns of persistent depression."

  • "I think of the frequent phone calls I receive from distressed men with varying degrees of hair loss who have used 5 alpha reductase inhibitors and now have newly manifested sexual and cognitive complaints that often persist despite discontinuation of the 5 alpha reductase inhibitor... In general, these patients feel deceived because of the lack of information warning them of potential sexual side effects. The majority feels strongly that the sexual problems are far worse than the hair loss concerns."

  • "...At the end of the day, because sex steroid hormones are critical for genital organ structure and function, depriving young men of a critical sex steroid — dihydrotestosterone — affects sexual function."

  • "... The 5 alpha reductase enzyme ALSO metabolizes progesterone to 5 alpha-dihydroprogesterone and deoxycorticosterone to 5 alpha-dihydrodeoxycorticosterone. And in the brain, the products of 5 alpha reductase inhibitors are transformed by another group of specific enzymes known as 3 alpha-hydroxysteroid dehydrogenases, which reduces 5 alpha-dihydrotestosterone to 3 alpha, 5 alpha-androstane 17b-diol (3a-diol), and 5 alpha-dihydroprogesterone to 3 alpha, 5 alpha-tetrahydroprogesterone (allopregnanolone). Similarly, 5 alpha-dihydrodeoxycorticosterone is further reduced to 3 alpha, 5 alpha-tetrahydrodeoxycorticosterone. " [THDOC]

  • "Theoretically, these important neurosteroid derivatives are UNNECESSARILY LOWERED (collateral damage) by 5 alpha reductase inhibitors for hair loss. These reduced important neurosteroid derivatives are thought to function in the central nervous system with important physiological functions including modulation of gamma aminobutyric acid type A receptor, sigma receptor function, nicotinic acetylcholine receptor, voltage gated calcium channels, and synaptic and brain plasticity.

  • "To translate into clinical terms, these physiological functions may impact mood, rhythm, stress, sleep, memory, anxiety, and sexual function."



  • FDA: 5-alpha reductase inhibitors (5-ARIs) may increase the risk of a more serious form of prostate cancer

    "[6-9-2011] The U.S. Food and Drug Administration (FDA) is informing healthcare professionals that the Warnings and Precautions section of the labels for the 5-alpha reductase inhibitor (5-ARI) class of drugs has been revised to include new safety information about the increased risk of being diagnosed with a more serious form of prostate cancer (high-grade prostate cancer). This risk appears to be low, but healthcare professionals should be aware of this safety information, and weigh the known benefits against the potential risks when deciding to start or continue treatment with 5-ARIs in men."

  • WebMD: Prostate Cancer Risk From BPH, Hair Loss Drugs

    "The prostate drugs Proscar, Avodart, and Jalyn and the hair-loss drug Propecia add to the risk of high-grade prostate cancer, the FDA warns. All of the drugs must change their labels to warn of the risk, which unexpectedly appeared in two different large-scale clinical trials.

    ... The male hair-loss drug Propecia has the same active ingredient as Proscar, although at one-fifth the dose. But the FDA says Propecia should carry the same prostate cancer warning as Proscar."


    PROPECIA Prescribing Information -

    Pg. 7 - Increased Risk of High-Grade Prostate Cancer with 5-Alpha Reductase Inhibitors
    "... 5α-reductase inhibitors may increase the risk of development of high-grade prostate cancer."

    PROSCAR Prescribing Information -

    Pg. 18 - Increased Risk of High-Grade Prostate Cancer

    "... Patients should be informed that there was an increase in high-grade prostate cancer in men treated with 5α-reductase inhibitors indicated for BPH treatment, including PROSCAR, compared to those treated with placebo in studies looking at the use of these drugs to prevent prostate cancer"

    PROSCAR Patient Information -

    Pg. 2 - "PROSCAR may increase the chance of a more serious form of prostate cancer."



The drug manufacturer recently updated the USA labeling for Propecia to include persistent ED as a reported side effect from Finasteride use:

PG 2:

  • "In general use, the following have been reported: breast tenderness and enlargement; depression; allergic reactions including rash, itching, hives and swelling of the lips and face; problems with ejaculation; testicular pain; difficulty in achieving an erection that continued after stopping the medication; and, in rare cases, male breast cancer. You should promptly report to your doctor any changes in your breasts such as lumps, pain or nipple discharge.  Tell your doctor promptly about these or any other unusual side effects."

This is a major change, in that it updates the USA labelling to match that of the European countries (Sweden, UK, Italy) which have had this verbage for some time.


Recent media coverage about persistent Finasteride side effects, including one young man's suicide.



March 2011: GEORGE WASHINGTON UNIVERSITY - STUDY PUBLISHED: Persistent Sexual Side Effects of Finasteride for Male Pattern Hair Loss

Media Awareness

A recent study by GW Professor Michael S. Irwig reveals persistent and possibly permanent side effects associated with a common hair loss drug.

March 23, 2011

Men taking medication for hair loss may suffer from prolonged and possibly irreversible sexual dysfunction, according to a recent study by Assistant Professor of Medicine Michael S. Irwig.

The study, recently published in the Journal of Sexual Medicine, reveals that finasteride--an antiandrogen that treats hair loss and is found in popular male pattern baldness drug Propecia--can cause persistent sexual dysfunction, including low sexual desire, erectile dysfunction and problems with orgasms.

While labeling on the medication in the U.S. currently warns about possible reversible sexual side effects, there is no reference to the effects being persistent, says Dr. Irwig, who conducted the study along with Swapna Kolukula of the Greater Baltimore Medical Center. Other countries, including the United Kingdom and Sweden, have documented persistent risks and required medical companies to include them in labeling.

Dr. Irwig first became aware of the problems caused by finasteride several years ago when he encountered several men who reported they had developed sexual dysfunction while taking the medication.

“It’s been very frustrating for a lot of these men because they’ve sought care from medical professionals who have looked at the literature and have not seen a risk of persistent sexual dysfunction,” says Dr. Irwig. “So a lot of these patients have been told to see psychiatrists and psychologists and that it’s all in their head.”

Dr. Irwig then noticed that men had reported sexual dysfunction for months after they stopped taking the medication.

“I came across a website called with more than 1,400 registered users—many young healthy men who developed the same sexual side effects from finasteride—and I discovered that nobody had published a series looking at these men—who they are, how long the sexual side effects lasted, what types.”

Dr. Irwig’s study included results from interviews with 71 men aged 21 to 46 years old to assess how long they took finasteride, the type and duration of sexual side effects and their sexual frequency before and after the medication.

Dr. Irwig discovered that 94 percent developed low libido, 92 percent developed erectile dysfunction and decreased arousal, and 69 percent developed problems with orgasm. On average, the men used finasteride for approximately 28 months but experienced persistent sexual side effects for an average of 40 months, from the time they ceased taking the medication to the time of the interview.

Dr. Irwig also found that the average number of sexual episodes per month dropped after finasteride use.

“It turns out that almost all the men had multiple sexual function problems,” says Dr. Irwig. “Before finasteride use, the men experienced average sexual activity of approximately 26 episodes per month, but after use, it came down to approximately eight per month —an almost two-thirds reduction.”

Twenty percent of patients I interviewed experienced persistent sexual dysfunction for more than five years, which makes me wonder if their persistent sexual dysfunction is permanent,” he adds.

Dr. Irwig says roughly 5 percent of men who take medicine will experience sexual dysfunction, but that “out of that 5 percent, it’s hard to tell how many will experience persistent symptoms.”

“We know that this is a potential problem, but we can’t quantify what the exact risk is. I can’t tell a man if he has a 1-in-100 chance, or a 1-in-1000 chance of developing persistent sexual dysfunction, but it’s pretty clear there’s a relationship here,” he says.

Topical Rogaine can be used as an alternative to Propecia —applied directly on the skin, it does not get absorbed by body and thus does not cause sexual side effects—but Dr. Irwig says Propecia is very effective in treating hair loss and thus is commonly prescribed.

So Dr. Irwig says it is crucial physicians treating male pattern hair loss discuss the possibility of persistent sexual side effects associated with finasteride with their patients.

“I think it’s very important that doctors who are prescribing this medicine talk about potential risks, so men can make an informed decision,” he says.


March 2011 - STUDY PUBLISHED: Adverse Side Effects of 5α-Reductase Inhibitors Therapy: Persistent Diminished Libido and Erectile Dysfunction and Depression in a Subset of Patients

Media awareness:

  • WebMD - Study: Sexual Side Effects of Hair Loss Drugs Persist

    ... But the review says less attention has been paid to uncommon but potentially devastating side effects of these medications.

    Those side effects can include anxiety, depression, loss of sex drive, difficulty getting or maintaining and erection, gynecomastia (growth of male breast tissue), and reduced semen production, which may affect fertility.

    What’s worse is that for some, these side effects persist, even when they stop taking the medication,
    according to the review.

    We don’t really understand why, but the symptoms remain persistent or irreversible and even if they get off the drug,” says study researcher Abdulmaged M. Traish, PhD, a professor of biochemistry at the Boston University School of Medicine. “They no longer regain what they had before. Biologically, something gets shut off and gets shut off once and for all.

    Traish thinks that may be because nerves that are maintained by dihydrotestosterone become permanently degraded and can’t be repaired even after men come off the medication.


  • USA TODAY: Sexual Side Effects From Propecia, Avodart May Be Irreversible - US News and World Report

    Use of dutasteride (Avodart) and finasteride (Proscar and Propecia) were linked to erectile dysfunction, depression and loss of libido in a review of existing studies. In a small percentage of cases, symptoms persisted even after the medication was stopped.

    For those men, "it's a life sentence," said lead researcher Abdulmaged M. Traish, a professor of biochemistry and urology at Boston University School of Medicine. "No sex. No desire. Potential depression," Traish added. Almost everyone who takes these drugs experiences some of these side effects, Traish said. "But, some experience it more drastically than others," he added.

    ... "We need androgen for erectile function, libido and ejaculation, and for just feeling good," Traish said. Noting that increasing numbers of patients report ongoing sexual problems after they stop taking the drugs, Traish said, "That's where the light should be shined."

    "I am not worried about those who stop taking the drug and get their life back, [my concern is] about those who stop taking the drug, but they don't get their life back," Traish said.


  • Popular Drugs For Common Male Health Problems Can Affect Their Sexual Health

    ... Dr. Irwin Goldstein, editor-in-chief of The Journal of Sexual Medicine, has seen and evaluated numerous such patients. He further explained the importance of this study.

    Young men are being prescribed 5 alpha reductase inhibitors as hair loss treatments that may negatively impact their sexual life, possibly for a prolonged time after stopping the medication.

    Older men with symptoms of lower urinary tract symptoms or fearful of prostate cancer, now have to deal with new onset sexual and mental health problems. The growing use of 5 alpha reductase inhibitors is causing concerns.

    Clearly more research is needed to better understand the basis for these drug-associated side effects but it is evident that 5 alpha reductase inhibitors prevent the synthesis of very critical central nervous system neurosteroids and lower a very important sex steroid hormone, dihydrotestosterone."



Dr. Andrew Rynne is a GP based in Ireland, vasectomy surgeon, men's health specialist and author. In March 2011, he wrote another blog post on the dangers of Propecia use and persistent side effects.

  • Benign Prostatic Hyperplasia

    "...hardly a week goes by that I am not being approached by yet another young man recently prescribed Propecia as a “treatment” for male pattern baldness.

    This drug has the capacity to obliterate their sexuality, not just for the time that they take the drug, but for all time.

    This vanity treatment can and does condemn many young men to a life sentence of sexual anhedonia, without feeling, desire or function, to otter misery and despair for which, as yet, we have no treatment
    . If you would like to know more about this you can share in their pain on

    I believe that potentially toxic medicine like this must be reserved for the indications for which it was first introducedand that is in the management of advanced prostate cancer with metastases. Here, as we all know, it can be life-saving or at any rate life-prolonging.

    Using it to treat a benign condition like BPH is, in my view, at best questionable. Using it to treat a naturally occurring condition in men like male pattern baldness, is reckless in the extreme."



It's official --  Merck USA has added "DEPRESSION" to the list of Finasteride side effects reported in post-marketing use:


Dec. 2010 - BBC RADIO 1 NEWS REPORT: Baldness drug Propecia 'risking men's sexual health'



    "Young men could be risking their sexual health by taking a commonly used anti-baldness drug, claim some doctors. They say finasteride, sold in the UK as Propecia, can cause serious side effects and isn't adequately labelled"



Dr. Andrew Rynne is a GP based in Ireland, vasectomy surgeon, men's health specialist and author. In October 2010, he wrote a blog post on the dangers of Finasteride use and persistent side effects.

  • Male Pattern Baldness and Propecia

    "... here is the real lie that Merck is giving you in its Patient’s Leaflet. Do you see that bit there about “went away in men who stopped taking Propecia –” That is simply not true and Merck know full well that it is not true. They know it is not true because I and hundreds of other doctors and thousands of patients have told them that these side effects do not always go away when you stop taking Propecia.

    "In some cases men who have taken Proscar, even for a few months, have unwittingly condemned themselves to a lifetime of Sexual Anhedonia, the most horrible and cruel or all sexual dysfunctions. I have spoken to several young men in my clinic in Kildare who continue to suffer from sexual anaesthesia and for whom all sexual pleasure and feelings have been obliterated for all time."



Dr. Alan Jacobs MD (neuroendocrinologist) confirms existence of persistent Finasteride side effects, the Post-Finasteride Syndrome, some treatments and possible causes.