Stinging Nettle Root for Benign Prostatic Hyperplasia
Stinging nettle root shows modest, mostly positive evidence for easing benign prostatic hyperplasia (BPH) urinary symptoms, but the proof is thin and not strong enough to recommend it as a substitute for proven medical treatment.
Why this grade7-layer evidence engine
The grade is Weak (Tier C) because the case rests on a small handful of mostly positive randomized trials rather than robust, replicated proof. Safarinejad's 6-month crossover RCT (PMID 16635963, n=620) found nettle root significantly improved IPSS symptom scores versus placebo (p<0.001), with better peak flow and lower residual urine. A smaller 8-week trial (PMID 23487561, n=100) pointed the same way, but its size and short duration limit confidence.
Two factors hold the evidence back. The often-cited long-term trial (PMID 15928959, n=257, 96 weeks) tested a saw palmetto plus nettle combination, so nettle's solo contribution can't be isolated, and it was industry-funded. The overall base is modest, dominated by Eastern European studies, lacks large independent Western replication, and has no Cochrane-grade meta-analysis confirming benefit for nettle on its own.
Authorities are cautious to unsupportive. EU EFSA has left botanical claims (including nettle) on hold pending review, and the US FDA treats it only as an unapproved dietary supplement. NIH/NCCIH calls the evidence 'limited' while noting nettle is generally well tolerated, though its tannins can interfere with iron absorption. Treat it as an optional adjunct at best, not a replacement for first-line BPH therapy.
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 = 0.464
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 無高階證據可裁決
- 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