Feinberg School of Medicine Epidemiology Study Suggests Tens of Thousands of Cases of Post-Finasteride Syndrome in Young Men Taking Finasteride for Hair Loss
1.19% of men 16 to 42 years old with no prior history of sexual dysfunction taking low-dose finasteride for more than 205 days developed persistent erectile dysfunction (ED) lasting ≥ 90 days after discontinuation of therapy (PED)
The risk of PED in these young men increased over time with longer duration of finasteride therapy
One-third of young men with onset of new ED while taking low dose finasteride eventually developed PED
SOMERSET, N.J., March 9, 2017 – More than one percent of young men who took finasteride for 206 days or longer developed persistent erectile dysfunction (PED) that lasted an average of 4.2 years after drug discontinuation, according to a new study published today in PeerJ.
In all, researchers examined the electronic medical records (EMR) of 4,284 men ages 16 to 42 with no prior history of sexual dysfunction who were exposed to ≤ 1.25 mg per day of finasteride, the dose commonly used to treat hair loss.
Titled Persistent erectile dysfunction in men exposed to the 5α-reductase inhibitors finasteride or dutasteride, the study was conducted at Northwestern University’s Feinberg School of Medicine by a team of nine researchers led by Steven M. Belknap, MD, Assistant Professor of Dermatology.
Key conclusions of the study, which was conducted using a repository of EMRs for 691,268 men ages 16 to 89 years from 1992 to 2013, are as follows:
- Men 16 to 42 years old without prior sexual dysfunction exposed to finasteride ≤ 1.25 mg/day were more likely to have new ED (p < 0.0001) and new low libido (p < 0.0001). Of these 4,284 men, 34 (0.8%) developed PED with a median duration of 1,534 days after drug discontinuation.
- Of the 103 young men with new ED, 34 (33%) developed new PED. Not included in this statistic were young men with new persistent ED who continued to take finasteride. PED developed in 1.19% of men with > 205 days of finasteride exposure.
- The multivariable model predicting new PED in young men had one variable: duration of finasteride exposure. Young men with > 205 days of finasteride exposure had a 4.9-fold higher risk of PED (p < 0.004) than men with shorter exposure. The magnitude of risk of PED associated with longer duration of finasteride exposure was greater than all other risk factors and was independent of age.
- The finding of a consistent effect provides evidence of an intrinsic relationship between duration of finasteride or dutasteride exposure for any clinical indication and PED.
“This study is the first to establish the extent of finasteride’s negative impact on sexual health based on a large critical mass of medical records,” said Dr. John Santmann, CEO of the PFS Foundation, which funded the study together with grants provided by the National Institutes of Health.
“The statistical results from this study should come as a wake-up call to dermatologists, internists and other MDs who regularly prescribe the drug. More than one out of every 100 men who take finasteride long term for hair loss will suffer devastating, long-term, and possibly permanent damage to their sexual health,” he added.
Please download the full study here.
Post-finasteride syndrome occurs in men who’ve taken finasteride to treat hair loss, or enlarged prostate glands. Reported symptoms include: loss of libido, erectile dysfunction, depression, suicidal ideation, anxiety, panic attacks, Peyronie’s disease, penile shrinkage, gynecomastia, muscle atrophy, cognitive impairment, insomnia, severely dry skin and tinnitus. The condition often has a life-altering impact on victims and their families, such as job loss and the breakup of marriages and romantic relationships, while also being linked to suicides.
In June 2015, Dr. Belknap published a related study in JAMA Dermatology titled Adverse Event Reporting in Clinical Trials of Finasteride for Androgenic Alopecia. According to that meta-analysis:
“Of 34 [finasteride] clinical trials, none had adequate safety reporting, 19 were partially adequate, 12 were inadequate, and 3 reported no adverse events… Available toxicity information from clinical trials of finasteride in men with [androgenic alopecia] is very limited, is of poor quality, and seems to be systematically biased… Published reports of clinical trials provide insufficient information to establish the safety profile for finasteride in the treatment of AGA.”
As of March 2, 2017, the World Health Organization Programme for International Drug Monitorings database of adverse drug reactions contained 13,554 finasteride ADRs, including 2,694 reports of erectile dysfunction, and 3,109 psychiatric disorders including 43 completed suicides and 32 suicide attempts.
In March 2015, the U.S. National Institutes of Health listed PFS on its Genetic and Rare Diseases Information Center, noting that “some patients who have taken finasteride have referred to side effects such as sexual dysfunction and depression (sometimes severe)… Studies sponsored by the NIH and other organizations are underway to better understand the effects of 5-alpha reductase inhibitor drugs.”
About the PFS Foundation
Headquartered in Somerset N.J., the Post-Finasteride Syndrome Foundation was established in July 2012 as a 501(c)(3) organization, with private grants from families in the U.S. and abroad. Tax-deductible financial donations to the nonprofit organization can be made via PFSFoundation.org, which also houses patient-recruitment information on active clinical studies, published research, research goals, and media reports about PFS. In July 2015, the PFS Foundation established The Southwest Brain Bank in the Department of Psychiatry at the University of Texas Health Science Center, whose mission is to collect and study postmortem human brain and spinal cord tissue in patients with PFS in order to better understand the pathology and etiology of the condition.