Medically reviewed on June 7, 2018
What are Nettles?
Nettles are perennial plants native to Europe and found throughout the United States and parts of Canada. The plant has dark green serrated leaves that grow opposite one another along the stalk. The leaves contain bristles that transmit irritating chemicals upon contact.
Urtica dioica and Urtica urens
Nettles are also known as stinging nettles and soii (Kashmiri).
What is it used for?
This plant is known for its stinging properties. However, it has been used in traditional medicine to increase the amount of urine excreted, suppress muscle spasms, promote the discharge of phlegm from the respiratory tract, and treat for asthma. The juice was said to stimulate hair growth when applied to the scalp. Extracts of the leaves have been used on the skin for the treatment of rheumatic disorders. Other folk medicine applications include wound healing, treatment of dandruff and greasy hair, and gastric juice secretion. Claims of activity against diabetes, cancer, eczema, hair loss, rheumatism, and aging have not been proved. The tender tips of young nettles have been used as a cooked pot herb in salads. It is considered to be a nourishing plant and has been used to treat scurvy. A combination product includes nettle to treat stomach inflammation.
The primary use of nettles is in the management of symptoms due to benign prostatic hyperplasia (BPH), diabetes, and arthritis. However, limited clinical trials are available.
What is the recommended dosage?
Freeze-dried nettle leaf 600 mg has been used in a clinical trial for allergic rhinitis. Clinical trials for BPH have used aqueous extracts of U. dioica root 360 mg daily over 6 months and methanol root extract 600 to 1,200 mg daily for 6 to 9 weeks. Commercial preparations are often not standardized.
Nettle preparations should not be used in pregnancy and lactation or in children younger than 12 years.
Avoid use. Documented adverse effects.
None well documented.
Nettles are known primarily for causing skin irritation following contact. Radix urticae extracts and other nettle preparations are generally well tolerated, with minor, short-term stomach effects, including diarrhea, stomach pain, and nausea.
The oral toxicity of nettle preparations is considered to be very low. DNA damage and cancer induction studies were negative for the aqueous extract.