Chronic & Persistent Sexual Side-Effects of Finasteride for Male Pattern Hair Loss

Finasteride, better known by its trade name "Propecia", has been associated with adverse sexual side effects in multiple randomized, controlled trials for the treatment of male pattern hair loss.
In an effort to update patient information in regards to the lingering effects of the drug after discontinuation, the Medicines and Healthcare Products Regulatory Agency of the United Kingdom and the Swedish Medical Products Agency have included a statement that reads as follows: "persistence of erectile dysfunction after discontinuation of treatment with Propecia has been reported in post-marketing use."
A recent study sought to characterize the types and duration of persistent sexual side effects in otherwise healthy men who took finasteride for "male pattern hair loss". Within this study, there were standardized interviews with 71 otherwise healthy men aged 21 to 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. The types and duration of sexual dysfunction and the changes in perceived sexual frequency and sexual dysfunction score between pre- and post-finasteride use were as follows:
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 average number of sexual episodes per month dropped and the total sexual dysfunction score increased for before and after finasteride use. The average 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.

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