Urtica dioica (L)
Synonyms and Common names: Urticae herba, Urticae radix, Stinging nettle, common nettle
German = Grosse brandnetel, French = Grande ortie, Spanish = ortiga, Italian = Grande ortica
Order: Labiatae
Description: Urtica dioica is a native British perennial growing in damp forests or wherever land has been disturbed by Man. It has a richly-branched yellow rhizome, which spreads which over large areas, and from which grow numerous erect, quadrangular stems. These are up to 120cm tall and are covered with long stinging hairs and short bristly hairs. The opposite, stalked, cordate or lanceolate leaves are serrated at the margin and covered on both sides with stinging hairs. The flowers are unisexual, the plants dioecious, although monoecious ones do occur. The flowers are arranged in drooping panicles, growing in groups from the upper leaf axils. The male inflorescences are erect and shortly branched, with four perianth segments and four stamens. The female flowers have two perianth segments and a superior ovary with a stalkless stigma. The fruit is an achene.
Parts used: the leaves or aerial parts of young plants; roots
Collection: the leaves are collected from June to October during the flowering period, the roots in spring and autumn.
Constituents: Leaves: Flavonoids (isoquercitin, rutin); acrid components, particularly in the stinging hairs (including histamine and 5-hydroxytryptamine, formic acid, volatile and resinous acids); silica, glucoquinone, tannins, ascorbic acid and other minerals and vitamins in appreciable levels. Root: polysaccharides, sterols and sterol glucosides, lignans, ceramides, fatty acids, monoterpene diols and glucosides
Actions: mild diuretic, astringent, tonic, haemostatic, dermatological agent; extracts are reported to have hypoglycaemic properties.
Indications: rheumatic conditions, uterine haemorrhage, cutaneous eruptions, infantile and psychogenic eczema, epistaxis, melaena. Specifically indicated in nervous eczema. The root is indicated in the symptomatic treatment of micturition disorders such as nocturia, pollakisuria, dysuria and urine retention and in benign prostatic hyperplasia.
Therapeutics and Pharmacology: Urtica is rich in iron and vitamin C, making it a useful remedy in anaemia and other debilitated states, the presence of the vitamin C ensuring that the iron is properly absorbed. The herb has an important effect on the kidney and on fluid and uric acid excretion, so is of benefit in gout and other arthritic conditions, particularly if there is an element of anaemia. The painful, irritant effect of the sting is lost on drying or heating with water, but if preserved in cold alcoholic tincture the irritant action is preserved. A tincture of the fresh leaf applied locally to an inflamed joint will induce counter-irritation and produce reddening over the joint. Blood is thus flushed through the area and out to the surface of the skin, where the toxins may even be taken off in the fluid of a burst blister.
Urtica is also of benefit in chronic skin conditions such as eczema, helping to cleanse the body of accumulated toxins. An infusion of the dried leaf is effective in helping to control dandruff and hair loss on the scalp. As a haemostatic and astringent, Urtica helps check wound bleeding and to treat menorrhagia; it is also used for haemorrhoids and can be taken internally to treat gastric and intestinal problems. The powdered leaves were traditionally used as a snuff to arrest nosebleeds.
Urtica is known to stimulate milk flow in nursing mothers, and is often used in this way by farmers for their stock. It has been shown experimentally to have both hypoglycaemic and hyperglycaemic properties, the hypoglycaemic component being ‘urticin’.
In a clinical trial, men with benign prostatic hypertrophy (Stages I and II) were treated with a dried standardised Urtica root extract for 20 weeks. A morphologically relevant effect on the prostate adenoma cells was found that may be due to competitive inhibition by the extract of the binding capacity of SHBG (sex hormone binding globulin). An increased binding capacity of SHBG to testosterone and dihydrotestosterone results in hyperplasia as a compensation for a decrease in hormones. Other clinical trials have reported improvements in urinary flow, and reduced urinary frequency, nocturia and residual urine after six months treatment.
Combinations: Urtica combines well with Arctium root in any detoxifying regime.
Caution: In a few individuals, exposure to the histamine in fresh nettles can be extremely dangerous. However, in the dried or cooked state nettles are completely non-toxic and may be eaten freely as a vegetable or drunk as an infusion.
Preparation and Dosage: (thrice daily)
Regulatory Status: GSL Schedule 1
Dried herb: 3-6g or by infusion
Liquid Extract 1:1 in 25% alcohol, 2-4ml
Tincture 1:5 in 45% alcohol, 2-6ml
Fresh juice: 5-10ml
Additional Comments: The Romans treated rheumatic conditions by flaying their joints with fresh nettles so as to stimulate blood circulation. Nettles are a good source of chlorophyll, and are a traditional spring tonic. In spring, the fresh green leaves can be cooked and eaten like spinach or made into a soup. Urtica urens (L), the small, or annual nettle, is also used medicinally, and has similar actions to Urtica dioica. U. urens is prescribed in homoeopathic medicine for rheumatic pain, burns and nettle rash.
Bibliography
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