Rosemary Oil for Androgenetic Alopecia
Verdict: Taiwan Regulatory Restriction
Across 5 PubMed studies, the evidence for Rosemary Oil in Androgenetic Alopecia grades Tier C — weak evidence.
C 🟠 C Weak Evidence Taiwan Regulatory Restriction
Why this grade7-layer evidence engine
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Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditableRaw score 0.63
D
C
B
A
S
← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
C · Taiwan Regulatory Restriction
Confidence
47%
Conflicting evidence
Evidence level
E2
Multiple high-quality MAs (≥2 independent, consistent)
▸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 = 0.625
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (2 篇 > 0 negative)
- tier_strict_requirement_check — | B→C 因 scope.conflation_risk=true 且 L11 獨評較低 (B7-2 tier cap)
- detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status
PubMed studies (5)L2 · primary research & systematic reviews
Relative Efficacy of Conventional Monotherapies and Select Nonconventional, Over-the-Counter Products for Male Androgenetic Alopecia: A Network Meta-Analysis Study
Finding: Bayesian network meta-analysis of 24 trials covering 8 conventional drugs and 7 OTC products: topical rosemary oil produced +19.53 hairs/cm2 at 24 weeks (comparable to topical minoxidil at +18.96), but topical minoxidil 5% twice daily was overwhelmingly the most effective treatment (SUCRA 99.8%), with rosemary/melatonin ranking far below the conventional drugs.
View on PubMed Comparative Effect of Conventional and Non-Conventional Over-the-Counter Treatments for Male Androgenetic Alopecia: A Systematic Review and Network Meta-Analysis
Finding: Bayesian NMA of 15 trials (9 active comparators): topical rosemary oil gave a statistically significant but modest +10.63 hairs/cm2 vs control (95% CI 0.82 to 20.89), and was significantly inferior to topical minoxidil 5% (mean difference 19.53 hairs/cm2 favoring minoxidil, 95% CI 6.52 to 32.68).
View on PubMed Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: a randomized comparative trial
Finding: In 100 AGA patients (50 rosemary 0.1% vs 50 minoxidil 2%), both arms significantly increased hair count from baseline at 6 months (P<0.05) with no significant difference between arms (P>0.05), and scalp itch was significantly more frequent with minoxidil; the suboptimal 2% comparator and absence of a placebo arm limit interpretation.
View on PubMed Rosmagain as a Natural Therapeutic for Hair Regrowth and Scalp Health: A Double-Blind, Randomized, Three-Armed, Placebo-Controlled Clinical Trial
Finding: In 90 HEALTHY (non-AGA) subjects, a rosemary-lavender oil blend raised hair growth rate +57.73%, thickness +68.70%, and density +32.21% vs baseline over 90 days (all p<0.0001) versus coconut-oil control, but it tests blends rather than isolated rosemary, is industry-funded (Soulflower), and was not conducted in diagnosed AGA patients.
View on PubMed Randomized trial of aromatherapy. Successful treatment for alopecia areata
Finding: In 86 ALOPECIA AREATA (not AGA) patients, an essential-oil blend of thyme+rosemary+lavender+cedarwood in carrier oils improved 44% (19/43) vs 15% (6/41) with carrier oil alone (P=0.008); it studies a different disease and a 4-oil blend, so it cannot isolate rosemary for AGA.
View on PubMed Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …
L4a US FDA
Neutral
21 CFR Citation: 182.20 | Permitted Use: FLAVORING AGENT OR ADJUVANT | FEMA No.: 2992 | CAS Registry Number: 8000-25-7 source↗
L4b EU EFSA
Neutral
1,548 claims on 'botanicals' have been placed on hold by the Commission pending further consideration on how to proceed with these source↗