TLDR Finasteride improves hair growth and satisfaction in men with male pattern baldness but may cause sexual side effects.
In 1997, Dr. Wayne Elwood discussed the psychological impact of hair loss and the clinical trials of finasteride, a new treatment for androgenetic alopecia (male pattern baldness, MPB). Finasteride, a 5α-reductase inhibitor, was evaluated in large multinational, placebo-controlled, double-blind studies. Results from two phase III trials involving over 1,500 men showed that finasteride 1 mg/day led to a mean increase of 107 hairs in a 1 inch diameter circle after one year, and it prevented further hair loss, improved hair growth and appearance, and increased patient satisfaction. Another study with 326 men showed finasteride significantly improved frontal scalp hair counts after 12 months. Finasteride was well tolerated, with a small percentage experiencing decreased libido or erectile dysfunction, which often resolved with continued treatment or upon discontinuation. Finasteride was not recommended for women of child-bearing potential due to the risk of birth defects. At the time, finasteride was undergoing regulatory review for MPB treatment and was not yet available for this indication globally.
32 citations,
March 2020 in “Drug Design Development and Therapy” Finasteride shows promise for female hair loss, but more research needed.
6 citations,
April 2016 in “PubMed” The review found that women using hair loss drugs like finasteride and dutasteride rarely reported sexual side effects.
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January 2007 in “The Year book of dermatology” Finasteride with oral contraceptive improves hair loss in 62% of premenopausal women.
72 citations,
January 2004 in “Dermatology” Finasteride can slow hair loss and promote growth in postmenopausal women.
38 citations,
June 2003 in “Journal of Investigative Dermatology Symposium Proceedings” Finasteride effectively improves hair growth and slows hair loss in men with male pattern baldness.
92 citations,
October 2002 in “Journal of The American Academy of Dermatology” Finasteride improves hair loss in women with hyperandrogenism.
10 citations,
June 2001 in “PubMed” Finasteride is effective in growing hair and stopping hair loss in men with mild to moderate alopecia.
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187 citations,
June 1999 in “Journal of The American Academy of Dermatology” Finasteride effectively treats frontal hair loss with few side effects.
581 citations,
October 1998 in “Journal of The American Academy of Dermatology” Finasteride safely and effectively treats male pattern hair loss, but may cause reversible sexual issues and harm male fetuses.
