How does Nettle Herb Description Works?
2 December 2007Taxonomic class
Urticaceae
Common Trade Names
Nettles Capsules, Nettles Liquid Extract
Common Forms
Available as capsules (Iso mg, 300 mg) and dried leaf and root extract or tincture.
Source
The active chemical components are found in the leaves, stems, and roots of Urtica dioica, a perennial herb of the nettle family. It is one of three species that are native to Europe and is naturalized throughout the United States and parts of Canada.
Chemical Components
Nettle roots and flowers contain scopoletin, steryl derivatives, lignan glucosides, and flavonol glycosides. The roots contain phenylpropanes and lignans. The plant has B-group vitamins as well as vitamins C and K and steroid-related compounds such as sitosterol. The stinging, hairÂlike projections on the stems contain amines, such as histamine, serotonin, and choline, and formic acid. The lectin found in the roots is specific to this plant and may help to standardize preparations. Actions
Nettle acts primarily as a diuretic by increasing urine volume and decreasing systolic blood pressure. It has been observed to stimulate uterine contractions in rabbits, but the mechanism is unknown.
Other compounds identified have known pharmacologic activity. The U dioica agglutinin, a lectin protein, has immunostimulating activity. Scopoletin has anti-inflammatory activity. A 20% methanolic extract of stinging nettle roots inhibited benign prostatic hyperplasia (BPH) in mice . The plant extract was effective in reducing urine flow, nocturia, and residual urine in human patients. Another study of stinging nettle extract reported it to have an antiproliferative effect on human prostatic cancer cells .
Reported Uses
Nettle has been used to treat rheumatism and is claimed to be helpful as an antispasmodic and an expectorant. The leaves have been smoked to treat asthma. Nettle tea has been used to treat cough and tuberculosis. the juice has been applied to the scalp to stimulate hair growth. The plant’s styptic or astringent action has been useful for treating nosebleeds and uterine bleeding. Other claims include treatment of cancer, diabetes, eczema, and gout and wound healing.
Nettle’s diuretic properties have prompted its use in heart failure, hypertension, and urinary, bladder, and renal disorders. It was studied with other herbs as a bladder irrigant for treating prostatic adenoma in humans and was found to reduce postoperative blood loss, bacteriuria, and inflammation. The German Commission E recognizes this irrigant for treating urinary tract inflammation and for preventing and treating kidney gravel. Nettle is widely used in Germany for the early treatment of BPH and has been shown to be effective for treating allergic rhinitis . However, there is stronger evidence for the use of saw palmetto, beta-sitosterols, and pygeum in the treatment of BPH than for nettle.
Dosage
For allergic rhinitis, 150 to 300 mg in capsule form P.O. t.i.d., as needed.
Root: 4 to 6 g P.O. daily.
Tea: 1 or 2 tsp of dried herb mixed in 1 cup of boiling water; up to 2 cups P.O. daily.
Tincture: IS to 1 tsp P.O. up to b.i.d.
Adverse Reactions
Skin: contact urticaria (leaves).
CV: edema (internal use).
GI: abdominal distress, diarrhea, indigestion (internal use).
GU: oliguria (internal use).
Interactions
Diuretics: May potentiate effects. Avoid administration with nettle.
Contraindications and Precautions
Nettle is contraindicated in pregnant or breast-feeding women because of its diuretic and uterine stimulation properties. It is also contraindicated in children under age 2. Use cautiously and in reduced doses in older children and adults over age 65.
Special Considerations
Advise the patient to eat foods high in potassium, such as bananas and fresh vegetables, and to replenish electrolytes lost through diuresis.
Caution the patient against self-medicating with nettle for BPH or to relieve fluid accumulation associated with heart failure without approval and supervision of a health care provider.
Alert If rubbed against the skin, nettles can cause intense burning for 12 hours or longer. Instruct the patient to wash thoroughly with soap and water, use antihistamines and steroid creams, and wear heavy gloves if the plant is to be handled.
Points of Interest
The FDA considers this herb to be of undefined safety.
Nettle plants were used in weaving in the Bronze Age; archeologists have found burial shrouds made of nettle fabric.
Nettle juice was an ingredient in hair-growth preparations in the 19th century.
Native American women believed that nettle tea eased delivery and stopped uterine bleeding after childbirth.
Commentary
Despite its traditional use for several conditions, the only proven pharmacologic action of nettle is as a diuretic. It is considered relatively safe in the amounts recommended, and adverse effects from the oral form are rare. The herb has been studied in the treatment of allergic rhinitis, BPH, and osteoarthritis and as a component in postoperative bladder irrigation, but more studies are needed to determine its role for these uses.
Tagged under:benign prostatic hyperplasia, group vitamins, Herbal Medicines, prostatic cancer, stimulate hair growth, systolic blood pressure urtica dioica
