Legacy AI grade · Sources dated 2026-06-01. Not expert reviewed. Coverage is limited to the listed sources. About the new summary workflow
Finasteride for Androgenetic Alopecia
For men with androgenetic alopecia, daily oral finasteride is consistently shown to slow shedding and modestly regrow hair, but the benefit reverses within about a year of stopping and carries sexual side-effect warnings. The evidence does not extend to women, where results are negative or too limited to support use.
Why this grade7-layer evidence engine
Multiple large double-blind RCTs in men point the same direction: the Propecia phase III pivotal trial (PMID 9777765, n=1,553), a frontal hair-loss trial (PMID 10365924, n=326), and a trial in men aged 41-60 (PMID 12695131, n=425) all reported significant hair gains at 1 mg/day, and a systematic review/meta-analysis (PMID 20956649, n=3927) pooled a consistent effect. This concordance is why the verdict is positive rather than neutral.
The grade stays at Preliminary rather than top-tier because the pivotal trials were industry-funded (a flagged conflict of interest) and regulators temper the picture. The US FDA approves finasteride but warns of sexual dysfunction that can persist after discontinuation; the UK NHS notes it does not work for everyone and is not NHS-funded for hair loss; and WHO pharmacovigilance data carry sexual-dysfunction safety signals.
Clinical bodies (Mayo Clinic, Harvard Health, the American Academy of Dermatology) back it as a first-line option for men, with Harvard citing 80-90% who maintain or regrow hair, while stressing that gains are lost within roughly a year of stopping. Crucially, this conclusion applies only to men: a trial in postmenopausal women found no benefit (PMID 11050579), and the female evidence is otherwise small and uncontrolled (PMID 16549704).
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditable▸View the full decision path (audit trail)
- compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.663
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (1 篇 > 0 negative)
- tier_strict_requirement_check — Tier 條件達標，未降階
- detect_disputes — 偵測到 0 個 hard + 1 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status