An observational retrospective evaluation of 79 young men with long-term adverse effects after use of finasteride against androgenetic alopecia

Andrology. 2016 Mar;4(2):245-50. doi: 10.1111/andr.12147. Epub 2016 Jan 13.


Concern regarding adverse effects of finasteride is increasing. We aimed to determine the type and frequency of symptoms in men having long-term sexual and non-sexual side effects after finasteride treatment (a condition recently called post-finasteride syndrome, PFS) against androgenetic alopecia (AGA). Subjects were recruited at the Urology Unit of the Trieste University-Hospital, and from a dedicated website. Out of 79 participants, 34% were white Italians, mean age was 33.4 ± 7.60 years, mean duration of finasteride use was 27.3 ± 33.21 months; mean time from finasteride discontinuation was 44.1 ± 34.20 months. Symptoms were investigated by an ad hoc 100 questions' questionnaire, and by validated Arizona Sexual Experience Scale (ASEX) and Aging Male Symptom Scale (AMS) questionnaires. By ASEX questionnaire, 40.5% of participants declared getting and keeping erection very difficult, and 3.8% never achieved; reaching orgasm was declared very difficult by 16.5%, and never achieved by 2.5%. By the ad hoc questionnaire, the most frequent sexual symptoms referred were loss of penis sensitivity (87.3%), decreased ejaculatory force (82.3%), and low penile temperature (78.5%). The most frequent non-sexual symptoms were reduced feeling of life pleasure or emotions (anhedonia) (75.9%); lack of mental concentration (72.2%), and loss of muscle tone/mass (51.9%). We contributed to inform about symptoms of PFS patients; unexpectedly loss of penis sensitivity was more frequent than severe erectile dysfunction and loss of muscle tone/mass was affecting half of the subjects. Further studies are necessary to investigate the pathophysiological and biochemical pathways leading to the post-finasteride syndrome.

Keywords: 5-alpha-reductase inhibitor; AGA; PFS; Post-finasteride syndrome; benign prostatic hyperplasia; erectile dysfunction; finasteride safety; finasteride side effects; follicle stimulating hormone; free testosterone; loss of libido; luteinizing hormone; male pattern hair loss; sexual dysfunction; testosterone.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 5-alpha Reductase Inhibitors / adverse effects*
  • Adult
  • Alopecia / drug therapy*
  • Finasteride / adverse effects*
  • Humans
  • Male
  • Reproduction / drug effects*
  • Retrospective Studies


  • 5-alpha Reductase Inhibitors
  • Finasteride