Finasteride is a synthetic 5-α reductase inhibitor, which prevents the conversion of testosterone to dihydrotestosterone and has been used for more than 20 years in the treatment of male pattern hair loss. Randomized, controlled trials have associated finasteride with both reversible and persistent adverse effects. In this pilot study, we sought to characterize sexual and nonsexual adverse effects that men reported experiencing at least 3 months after stopping the medication. Based on previous research on persistent side effects of finasteride, we constructed an Internet survey targeting six domains: physical symptoms, sexual libido, ejaculatory disorders, disorders of the penis and testes, cognitive symptoms, and psychological symptoms and was e-mailed to patients who reported experiencing symptoms of side effects of finasteride. Responses from 131 generally healthy men (mean age, 24 years) who had taken finasteride for male pattern hair loss was included in the analysis. The most notable finding was that adverse effects persisted in each of the domains, indicating the possible presence of a “post-finasteride syndrome.”

Aims To our knowledge no studies have sought to characterize clinically the global syndrome that some men experience after initiating and stopping finasteride therapy for MPHL. The researchers therefore set out in this pilot study to explore the extent to which generally healthy men with a recent history of taking finasteride for MPHL experience persistent physical, psychological, and cognitive effects after stopping the medication.

Method Design A web-based survey was constructed after conducting an extensive literature search of MEDLINE (restricted to the years 1995-2013) using the key words finasteride, sexual dysfunction, 5-α reductase, male pattern hair loss, Propecia, and side effects. Self-reported symptoms were also incorporated from more than 100 patients in one of the authors’ private practices. Questions on demographic characteristics (e.g., age, race and ethnicity, and general health) were included, as were questions on dose and duration of finasteride use and whether the participant was currently taking the drug. Questions were asked about symptom onset after starting and stopping therapy. Symptom onset was characterized as beginning immediately after initiating finasteride, 3 to 6 months or 6 to 12 months into the therapy, or never while taking finasteride. Physical symptoms included were gynecomastia, fatigue, muscular atrophy, and skin-related changes as were several questions pertaining to sexual libido, ejaculatory disorders, and changes to the penis and testes (specifically, penile and testicular shrinkage). Sexual adverse effects included on the survey were loss of morning erections, intermittent erectile dysfunction, and impotence. To assess cognitive side effects questions pertaining to cognitive impairment and psychological sequelae, including insomnia and suicidal ideation were included. The survey asked about the type of medical care men sought out for symptoms and about satisfaction with clinical assessment and treatments offered. The investigators were interested in whether subjects were hopeful that they would recover from their symptoms and asked them to qualitatively tell us anything else that they thought was important to their experience of taking finasteride for MPHL. Participants Subjects were recruited from two sources. First, an e-mail link to the online questionnaire was sent to 100 patients who had sought medical treatment at the office of one of the authors for persistent adverse effects (lasting 3 months or longer) related to the use of finasteride to treat MPHL. Second, the link was posted on Propeciahelp.com, an online forum for exchange of information about unresolved adverse effects of finasteride. The institutional review board of the City University New York, Hunter College, approved the study. Inclusion criteria for participation were the following: subjects were male, age 18 years or older, had taken finasteride for MPHL, and had experienced persistent adverse effects after taking the medication for at least 3 months. Exclusion criteria were a history of baseline sexual dysfunction or psychiatric condition. Subjects were provided a written consent form after accessing a link informing them that by completing the questionnaire they consented to participate. To minimize nonresponse bias a reminder was sent out 4 weeks after sending out the initial survey.

Results A total of 149 surveys were retrieved with 18 excluded because they were less than 70% complete. The overall response rate was 88% (n = 131). Survey data were entered and statistical analysis was performed using SPSS software (IBM, Armonk, NY). Descriptive statistics were used to delineate the men’s sociodemographic and health-related characteristics. Our analysis included 131 surveys. A significant proportion (n = 105, 80%) of the sample were collected from patients that were evaluated for persistent side effects after taking finasteride for more than 3 months and were seen as private patients in one of the authors’ clinical practice. Participants were men, ages 21 to 62 years (mean, 24 years; SD = 8.7). See Table 1 for sample demographics. Table 1. Subject Demographics (N = 131). View larger version Most participants (n = 124, 95%) had stopped taking the medication at the time of their participation. See Table 2 for data on duration of finasteride use and time since stopping the therapy. Overall, 93% (n = 121) of the sample reported that they had taken the 1-mg dose of finasteride; 84% (n = 108) reported that they had no symptoms while taking the medication but that symptom onset began (n = 89, 68%) immediately after discontinuing the medication. Study questions asked if they had taken the medication on more than one occasion and whether they experienced symptoms intermittently while they were off the medication and identified that 52% (n = 68) experienced symptoms. More than half of men reported that symptoms came on gradually over time while on the medication (n = 72, 55%). Table 2. Duration of Finasteride Use and Discontinuation (N = 131). View larger version Symptoms were divided into six categories: physical, sexual, ejaculatory, penile and testicular, cognitive, and psychological. As reported in Table 3, men reported physical symptoms that included fatigue, changes in musculature and skin texture and tone, and enlarged breasts. A greater proportion reported sexual dysfunction, including changes in libido, loss of morning erections, erectile dysfunction, and anhedonia in sex. Shrinkage of the penis and scrotum were reported, as well as changes in sensation. Behavioral and psychiatric symptoms were reported, as well, including memory and attentional disturbances, increased anxiety, and depressed mood. A significant number of respondents reported that they had been suicidal and felt a loss of hope. As to medical care sought out once symptoms appeared, participants said that they initially saw either an urologist (n = 50, 38%) or a primary care or internal medicine provider (n = 81, 62%). Many said their physician was unaware of the possible relationship between finasteride and their presenting symptoms. Respondents described that their physicians generally attributed physical symptoms as being psychological in nature and encouraged them to seek out psychiatric consultation (n = 53, 69%). Overall, men reported that they were frustrated and dissatisfied with the medical care that they received and their physicians’ lack of awareness and recognition of their symptoms as being valid (n = 121, 93%). Table 3. Specific Types of Symptoms Experienced (N = 131). View larger version

Acknowledgements The authors wish to thank participants for their willingness to share their experiences in this study. The investigators would also like to thank PropeciaHelp.com for allowing us to post this survey on their forum. We acknowledge Joy Jacobson for her help in editing the article before submission.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interests with respect to the research, authorship, and/or publication of this article. Funding

The authors received no financial support for the research, authorship, and/or publication of this article.