At a glance: Stinging nettle, Urtica dioica L. (with U. urens also represented in European monographs), provides several distinct medicinal drugs. Leaf/herb is traditionally used for urinary flow and musculoskeletal complaints, while root is used for lower urinary tract symptoms associated with benign prostatic enlargement. These are different plant parts with different chemistry, pharmacology and clinical literature.[1][2][3]
Botanical profile
- Important species: Urtica dioica L. and Urtica urens L.
- Common name: stinging nettle.
- Family: Urticaceae.
- Medicinal parts: leaf, aerial herb, and root.
- EMA herbal drugs: Urticae folium, Urticae herba, and Urticae radix.[1][2][3]
Leaf, herb and root are not the same medicine
The aerial parts and root are used for different therapeutic purposes:
- Leaf / herb: traditional urinary-flow support and musculoskeletal use.
- Root: lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH).
The EMA’s separate monographs reflect this distinction. In 2024–2025, revised monographs were finalised for both nettle herb and nettle root.[2][3]
Major constituents — aerial parts
Nettle leaf and herb contain:
- flavonoids such as quercetin- and kaempferol-related compounds;
- phenolic acids;
- minerals including potassium and silica;
- chlorophyll and carotenoids; and
- small amounts of other polyphenols and sterols.
Major constituents — root
Nettle root has a different profile, including:
- sterols, including beta-sitosterol-related compounds;
- lignans;
- polysaccharides;
- lectins; and
- phenolic and lipid-soluble constituents relevant to prostate research.[4]
Traditional use
Nettle leaf and herb have traditionally been used as a spring tonic, mineral-rich food herb and mild diuretic. Herbalists have used them for urinary-flow support, fluid retention, rheumatic aches and joint stiffness. Nettle has also been eaten as a cooked green and used in soups, teas and tonics.
Nettle root has a separate Western phytotherapeutic tradition for urinary hesitancy, frequency, nocturia and weak urinary flow associated with benign prostatic enlargement.
Contemporary herbal practice
Modern herbal practice treats nettle leaf/herb and nettle root as two different medicines. Leaf and aerial herb are commonly used as mineral-rich nutritive and urinary herbs and in musculoskeletal formulas; root is much more specifically used in prostate and lower-urinary-tract presentations. The distinction is so established that experienced herbalists will usually specify “nettle leaf” or “nettle root” rather than simply write “nettle”.
EMA regulatory assessment
The EMA maintains separate monographs for nettle leaf, nettle herb and nettle root. The revised herb monograph was finalised in 2024/2025 and covers therapeutic areas including pain/inflammation and urinary disorders, while the revised root monograph is specifically associated with urinary and genital disorders.[2][3]
Nettle root and lower urinary tract symptoms
Clinical research on nettle root has focused on men with lower urinary tract symptoms associated with benign prostatic hyperplasia. A large randomised placebo-controlled study reported improvements in symptom scores and urinary-flow measures over six months, although the wider review literature has historically regarded the evidence as less established than some other phytotherapies.[5][6]
A more recent 12-week randomised trial also reported improvement in symptom scores with a nettle-root extract.[7]
How might nettle root work?
Proposed mechanisms include effects on inflammatory pathways, sex-hormone-binding globulin, aromatase, prostate growth signalling and steroid-receptor-related pathways. A comprehensive review concluded that no single mechanism fully explains the root’s activity.[4]
Nettle herb and musculoskeletal use
Nettle herb has a long history in rheumatic and arthritic complaints. One unusual traditional practice is urtication—deliberately applying fresh stinging nettles to a painful area. A small double-blind crossover trial in thumb-base osteoarthritis reported greater pain and disability improvement after topical nettle sting than after the control leaf.[8]
This is a very different intervention from drinking nettle tea and should not be cited as evidence for oral nettle preparations.
Urinary-flow use of aerial nettle
Nettle leaf and herb are traditionally used as mild diuretic preparations to increase urinary flow. This use is separate from the prostate-focused root indications.
Unexplained oedema or urinary obstruction should not be self-treated simply because nettle is a “urinary herb”.
Safety
Cooked nettle and ordinary infusions are generally well tolerated. Fresh plants can cause intense local stinging, erythema and itching because of the hairs on the leaves and stems.
Root extracts may cause mild gastrointestinal symptoms in some people. Persistent or worsening urinary symptoms, blood in urine, urinary retention or recurrent infection warrant medical assessment.
Student note: common evidence traps
- Nettle root is not nettle leaf.
- BPH research should not be used as evidence for nettle tea.
- Urtication trials are topical fresh-leaf interventions, not oral phytotherapy.
- Do not treat diuretic use and prostate use as one mechanism.
- Check whether a study used U. dioica, U. urens or a combination.
- Persistent urinary symptoms require diagnosis even if an herbal product improves symptoms.
References
- European Medicines Agency. Urticae folium — Urtica dioica L.; Urtica urens L., folium. EMA.
- European Medicines Agency, Committee on Herbal Medicinal Products. Urticae herba — Urtica dioica L.; Urtica urens L., herba. European Union herbal monograph, Revision 1. EMA. Revised monograph published 2024, updated 2025.
- European Medicines Agency. Urticae radix — Urtica dioica L.; Urtica urens L., radix. European Union herbal monograph, Revision 1. EMA. Revised monograph published 2024, updated 2025.
- Chrubasik JE, Roufogalis BD, Wagner H, Chrubasik S. Comprehensive review of stinging nettle: Part II, Urticae radix. Phytomedicine. 2007. PubMed.
- Safarinejad MR. Urtica dioica for treatment of benign prostatic hyperplasia: randomised, double-blind, placebo-controlled study. PubMed.
- Phytotherapy for benign prostatic hyperplasia — systematic review. PubMed.
- Randomised controlled trial of Urtica dioica root extract in benign prostatic hyperplasia. PubMed.
- Randomised controlled trial of nettle sting for base-of-thumb pain. PubMed.
- Chrubasik JE, et al. Comprehensive review of nettle effect and efficacy profiles, Part I: Herba urticae. PubMed.
Additional materia medica sources
- ESCOP. Urticae folium/herba and Urticae radix, ESCOP Monographs.
- Blumenthal M, et al., eds. The Complete German Commission E Monographs. American Botanical Council; 1998.
- British Herbal Medicine Association. British Herbal Compendium, Volume 1 — Nettle Herb.
- Hoffmann D. Medical Herbalism. Healing Arts Press; 2003.
Last reviewed: 20 September 2026. Educational reference only; not an individual urinary or prostate diagnosis guide.
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