Studies on Finasteride marketed as Propecia®

Persistent Sexual Side Effects of Finasteride for Male Pattern Hair Loss

  1. Michael S. Irwig MD1,* and
  2. Swapna Kolukula MB BS2

Article first published online: 18 MAR 2011
DOI: 10.1111/j.1743-6109.2011.02255.x
© 2011 International Society for Sexual Medicine

The Journal of Sexual Medicine Volume 8Issue 6pages 1747–1753June 2011



Keywords: Erectile Dysfunction; Finasteride; Libido, 5 Alpha Reductase Inhibitor; Propecia; Sexual Side Effects



Introduction.  Finasteride has been associated with reversible adverse sexual side effects in multiple randomized, controlled trials for the treatment of male pattern hair loss (MPHL). The Medicines and Healthcare Products Regulatory Agency of the United Kingdom and the Swedish Medical Products Agency have both updated their patient information leaflets to include a statement that “persistence of erectile dysfunction after discontinuation of treatment with Propecia has been reported in post-marketing use.”




Study of Finasteride - Propecia®


Aim of the Study

Aim.  We sought to characterize the types and duration of persistent sexual side effects in otherwise healthy men who took finasteride for MPHL.

sexual medicine

Methods used in study

Methods.  We conducted standardized interviews with 71 otherwise healthy men aged 21–46 years who reported the new onset of sexual side effects associated with the temporal use of finasteride, in which the symptoms persisted for at least 3 months despite the discontinuation of finasteride.
Main Outcome Measures.  The types and duration of sexual dysfunction and the changes in perceived sexual frequency and sexual dysfunction score between pre- and post-finasteride use.

imageResults of the study

Results.  Subjects reported new-onset persistent sexual dysfunction associated with the use of finasteride: 94% developed low libido, 92% developed erectile dysfunction, 92% developed decreased arousal, and 69% developed problems with orgasm. The mean number of sexual episodes per month dropped and the total sexual dysfunction score increased for before and after finasteride use according to the Arizona Sexual Experience Scale (P < 0.0001 for both). The mean duration of finasteride use was 28 months and the mean duration of persistent sexual side effects was 40 months from the time of finasteride cessation to the interview date. Study limitations include a post hoc approach, selection bias, recall bias for before finasteride data, and no serum hormone levels.

Conclusion.  Physicians treating MPHL should discuss the potential risk of persistent sexual side effects associated with finasteride. Irwig MS and Kolukula S. Persistent sexual side effects of finasteride for male pattern hair loss. J Sex Med 2011;8:1747–1753