Finasteride / working resource
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How finasteride works
Finasteride for male pattern hair loss, with the evidence and its limits in plain view. What should I know about how finasteride works?
Open the Finasteride library ↗The Finasteride Male Pattern Hair Loss Study Group reported clinically significant increases in hair count (baseline = 876 hairs), measured in a 1-inch diameter circular area (5.1 cm2) of balding vertex scalp, with finasteride treatment: 107 and 138 hairs vs placebo at 1 and 2 years (P < .001).
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The Finasteride Male Pattern Hair Loss Study Group reported clinically significant increases in hair count (baseline = 876 hairs), measured in a 1-inch diameter circular area (5.1 cm2) of balding vertex scalp, with finasteride treatment: 107 and 138 hairs vs placebo at 1 and 2 years (P < .001).
Supporting record ↗The Study Group's 5-year report concluded that long-term treatment with finasteride 1 mg/day was well tolerated, led to durable improvements in scalp hair growth, and slowed the further progression of hair loss that occurred without treatment.
Supporting record ↗A systematic review and network meta-analysis of placebo-controlled trials concluded that finasteride in men was not statistically different from placebo. It included only trials reporting after 24 weeks, and its abstract discloses that one author was employed by the owner of a product it tested.
Supporting record ↗A meta-analysis of randomized controlled trials of 5α-reductase inhibitors found pooled relative risks for sexual dysfunction of 2.56 (95% CI = 1.48-4.42) in men with an enlarged prostate (BPH) and 1.21 (95% CI = 0.85-1.72) in men with androgenetic alopecia. Its authors concluded the association was not statistically significant in men with androgenetic alopecia.
Supporting record ↗A meta-analysis of 34 clinical trials of finasteride for androgenic alopecia found that none had adequate safety reporting, 19 were partially adequate, 12 were inadequate, and 3 reported no adverse events. Its authors concluded that the published reports provide insufficient information to establish the safety profile for finasteride in the treatment of androgenetic alopecia.
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