Root for the prostate; leaf for rhinitis. Extracts depending on the product.
Somewhat relieves the urinary symptoms of an enlarged prostate.
View the study (RCT) →⏱ 3 min read
Nettle is Urtica dioica, a plant common throughout Europe, Asia, and the Americas, known mainly for the stinging hairs on its leaves (responsible for the burning and itching sensation on contact with the skin), which contain a mixture of formic acid, histamine, serotonin, and acetylcholine; despite this defensive trait, nettle has a long history as a medicinal and food plant (cooked leaves, soups, infusions) in every culture with a European herbal tradition, with traditional indications that include urinary and prostate problems, joint pain, seasonal allergy, general strengthening, and mineral supply during convalescence.
The leaf and the root have different phytochemical profiles and distinct clinical applications: the leaf contains flavonoids, phenolic acids, carotenoids, minerals, and vitamins with a mild anti-inflammatory and antihistamine profile; the root contains lectins, sterols, lignans, and polysaccharides with specific effects on androgen metabolism and on benign prostatic hyperplasia, an important distinction when choosing the right product for each indication.
The indication with the best clinical evidence is mild to moderate benign prostatic hyperplasia, in which nettle root has shown significant improvements in symptom scales (IPSS), urinary flow, and post-void residual volume with doses of 600-1,200 milligrams of extract daily for 3-6 months, with an efficacy profile comparable to some traditional prostate herbal remedies (Serenoa repens or saw palmetto, Pygeum africanum) and with good tolerability; combinations with Serenoa are common and appear to offer additive benefits in some studies.
In seasonal allergic rhinitis, several small studies have shown significant improvements in nasal and ocular symptoms with supplementation at 300-600 milligrams of leaf daily for 1-2 weeks during the exposure period, an indication consistent with the antihistamine activity documented in vitro and with clinical support in integrative practice.
In osteoarthritis and mild inflammatory arthritis, several trials have shown modest improvements in pain and stiffness with supplementation for 4-12 weeks, a traditional indication with moderate clinical support; topical preparations (creams with nettle extract) are traditionally used for localized joint pain with variable subjective results.
Nettle leaf is one of the plants with the most complete mineral profile, particularly rich in iron, calcium, magnesium, potassium, manganese, and vitamins C and K; in people with mild iron-deficiency anemia or low mineral intake, strong infusions or leaves cooked as a vegetable can contribute to nutritional intake, a traditional indication with a solid nutritional basis, although modest in quantitative terms compared with specific pharmaceutical interventions.
The doses studied vary depending on the indication and the part used: for prostatic hyperplasia, 600-1,200 mg/day of root extract for 3-6 months; for seasonal allergy, 300-600 mg/day of leaf extract at the onset of and during allergen exposure; for traditional infusions, 1-2 teaspoons of dried leaf per cup, 2-3 times a day; commercial products can be confusing because they do not always clearly distinguish between leaf and root, an important consideration since the clinical indications are different.
Generally very well tolerated orally; the adverse effects described are rare and mild (mild digestive discomfort, occasionally skin rash); people taking antihypertensive drugs should monitor blood pressure because of possible mild potentiation; those taking diuretics should be cautious because of nettle's mild diuretic effect; those taking lithium should be cautious because of possible impairment of the drug's renal clearance; those taking antidiabetic drugs may experience potentiation of the hypoglycemic effect; in pregnancy, nettle may have a uterotonic effect at high doses, and therapeutic use during gestation is recommended against; in breastfeeding it has traditionally been used to stimulate milk production, although modern clinical data are limited; in people with calcium oxalate kidney stones, consumption should be moderated because of its significant oxalate content; the stinging hairs of fresh plants must be inactivated by cooking or drying before oral consumption.
Information, not medical advice. Scientific evidence reflects the quality of the studies.