5-Alpha Reductase Inhibitors and Erectile Dysfunction: The Connection

December 2008 in “ The Journal of Sexual Medicine ”

Fıkret Erdemır, Andrew Harbin, Wayne J.G. Hellstrom

5-alpha reductase inhibitors finasteride dutasteride erectile dysfunction ejaculatory dysfunction decreased libido nitric oxide synthase dihydrotestosterone 5ARIs ED EjD DHT

From the encyclopedia

Finasteride →

Frontline, gold standard treatment for combatting androgenic alopecia

Dutasteride →

Heavy duty finasteride that comes with higher risks

Studysummary This review highlights that sexual dysfunction associated with 5-alpha-reductase inhibitors is recognized in clinical literature, with erectile dysfunction being the most common adverse effect, followed by ejaculatory dysfunction and decreased libido.

Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer

The document reviewed the association between 5-alpha reductase inhibitors (5ARIs), such as finasteride and dutasteride, and sexual adverse effects (AEs) like erectile dysfunction (ED), ejaculatory dysfunction (EjD), and decreased libido. It found that sexual AEs were reported in clinical trials at rates ranging from 2.1% to 38%, with ED being the most common. These effects typically occurred early in therapy and lessened over time. A proposed mechanism for these dysfunctions involved decreased nitric oxide synthase activity due to reduced dihydrotestosterone levels. The study concluded that while the connection between 5ARIs and sexual dysfunction was evident, the exact mechanisms remained unclear, suggesting a need for future research to focus on understanding these pathophysiologic mechanisms to aid in prevention and treatment.

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13 / 13 results

research Finasteride 5mg and Sexual Side Effects: How Many Are Related to a Nocebo Phenomenon?

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research Evaluation of Sexual Function With an International Index of Erectile Function in Subjects Taking Finasteride for Androgenetic Alopecia

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In this study, treatment with 1 mg of finasteride was associated with stable sexual function, suggesting that sexual side effects may be less common than indicated in clinical trials.

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research Comparison of Finasteride and Alpha-Blockers as Independent Risk Factors for Erectile Dysfunction

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research Doxazosin and Finasteride Alone or in Combination: The PREDICT Study

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20 citations , April 2002 in “PubMed”

This study found that long-term treatment with finasteride 1 mg/day significantly improved scalp hair growth and was well tolerated in men with androgenetic alopecia over five years compared to placebo.

research Evaluation of Sexual Function in Subjects Taking Finasteride for the Treatment of Androgenetic Alopecia

36 citations , September 2001 in “Journal of The European Academy of Dermatology and Venereology”

This study found that sexual and erectile function in men taking finasteride 1 mg did not significantly differ from age-matched controls, suggesting sexual side effects may be less common than previously reported.

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