- Stinging Nettles;
- Greater nettle;
- Common nettle.
Indications & Historical Uses
Nettles have been widely used as food, medicine, cosmetics and clothing. The most recent indication in phytomedicine is in the treatment of urinary retention arising from early stages of benign prostatic hyperplasia (BHP). Usual dose is 4 – 6 grams (of the root extract) daily. Dried leaves of the nettle plant are commonly employed as a mild diuretic and their consumption does increase urine flow. Nettle leaves are ordinarily taken in the form of a tea. Tea is prepared with 3-4 teaspoonsful (about 4gms) of the botanical and 150ml of boiling water. One cup may be drunk 3 – 4 times daily together with additional water. This is not effective in the treatment of hypertension or edema of cardiac origin. Nettles have also been traditionally used as an important hair and skin tonic. The high quantity of silicon has made nettles highly useful in stimulating hair growth, improving condition of the hair and skin and treating dandruff. Nettles have been used externally and internally to treat eczema. Nettle juice has been used as an astringent or styptic to stop bleeding and to treat wounds. The best known use of nettles is in the treatment of gout and other rheumatic conditions. A decoction of the leaves or the expressed juice has been known to mobilize uric acid from the joints and eliminate it through the kidneys. Recently a randomized, double blind clinical trial has shown beneficial effects of nettles in the treatment of allergic rhinitis or hay fever. Historically, nettles has been used for the following:
- Arthritis, tendonitis, sciatica;
- Hair loss;
- Allergic rhinitis, hay fever, sinus congestion;
- Astringent; wound healing; styptic;
- Mild diuretic;
- Benign Prostatic hyperplasia;
- Stimulate lactation;
- Hypoglycemia (low blood sugar).
Contraindications & Precautions
None known at present – (See Caution.) Avoid its use in cardiac and renal impairment and in diabetes. Some experts believe that nettle causes poor glycemic (blood sugar) control in patients with diabetes and therefore diabetics should not use nettles.
Known Drug Interactions:
None known at present.
Nettles are a rich source of trace elements, absorbing and accumulating them. As mentioned in the active ingredients, nettles contain formic acid and neurotransmitters acetylcholine, 5 hydroxy-tryptamine and histamine which are responsible for the sting. It is these substances which are thought to endow nettles with their anti-arthritic, antispasmodic, diuretic, astringent, tonic and expectorant properties. Nettle also contains steroidal and phenolic substances which inhibit the prostatic enzymes, and this leads to the beneficial structural changes in the prostate in patients with BPH [Benign prostatic hypertrophy]. Nettle suppresses cell growth of the prostate. Other compounds that have been isolated include flavonoids, vitamins and antioxidants – all of these may contribute to its therapeutic benefits. German E Commission has approved nettle for irrigation in inflammation of the urinary tract and in the prevention and treatment of kidney stones .
- Formic acid;
- Minerals (iron, magnesium, silica, potassium, sulphur);
- Vitamins A; C; B2 and B5 and chlorophyll;
- N.B. Standardized extract should contain 1 – 2 % plant silica.
Stinging Nettles are found all over the world. Originally found in Europe and Israel. They derive their name from the presence of stinging hairs on their leaves and stems which, when touched, inject formic acid and histamine into the skin and cause urticaria.
For processing, the young top leaves are harvested from plants grown in clean, uncontaminated areas. Extraction is by traditional alcohol and water extraction. The extract is concentrated to a paste, prepared as a liposoluble liquid for cosmetic use or spray dried to produce a stable pure powder.
A.Y.Leung. Encyclopedia of natural ingredients used in food, drugs and cosmetics.
Krstic-Pavlovic, N. and Dzamic, R. (1985) Astringent and mineral components in the leaves of nettle (Urtica dioica, L.) from many natural locations. Agrochemija. 1985:191-198.
Smith, T.A. (1977) Tryptamine and related compounds in plants. Phytochemistry. 16:171.
Caceres, A. et al. (1987) Diuretic activity of plants used for the treatment of urinary ailments in Guatemala. J. Ethnopharmaco. 19:233-245.
Baraibar, C. et al. (1983) Acute and chronic toxicity studies on Nettle (Urtica dioica, L.). An. Bromatol. 35:99-103.
Mittman, P.(1990) Randomized, Double-blind study of freeze-dried Urtica Dioica in the treatment of allergic rhinitis. Planta medica 56:44-47.
Back To Index