Scientific Name: Nettle Root
Other Names: Stinging Nettle Root, Urtica Radix, Urtica dioica radix

Who is this for?

Uses

The roots of stinging nettle may be used to relieve the symptoms of benign prostatic hyperplasia (BPH)--a non-cancerous enlargement of the prostate gland. The prostate is part of the male reproductive system. For most men, BPH is a normal part of aging. However, the urethra, the tube that carries urine out of the body, passes through the prostate gland. An enlarged prostate may cause men to have trouble starting or maintaining urination, need to urinate more often, have urine leaks, or need to urinate during the night. Stinging nettle root contains chemicals that may prevent or delay the growth of prostate cells by interfering with an enzyme involved in hormone conversion. In several studies, nettle root products have shown general effectiveness for relieving the symptoms of BPH, although they usually do not cause the prostate to decrease in size. Frequently, it is included with other herbals such as Pygeum africanum and saw palmetto in "Prostate Formulas".

Nettle root is also being studied for potential anti-inflammatory and blood-pressure lowering effects. In studies of laboratory animals, nettle root extract seemed to reduce artificially produced inflammation. How it worked is not known. Results from other laboratory studies show that nettle root may relax blood vessels and help to stabilize the force of heartbeats. Both of these actions may contribute to lowering blood pressure. All these possible effects of nettle root need further study, however.

Precautions

Very little information is available on how nettle root might affect a developing fetus, an infant, or a small child. Therefore, its use is not recommended during pregnancy, breast-feeding, or early childhood.

What side effects should I watch for?

Side effects attributed to nettle root seem to be rare and mild. They include:

• Nausea
• Rash
• Sweating
• Upset stomach

What interactions should I watch for?

No interactions between nettle root and prescription drugs, non-prescription drugs, other herbal products, or foods have been reported. However, because few reliable studies of nettle root have been conducted in humans, its possible interactions are not understood completely.

Some interactions between herbal products and medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals. For specific information on how nettle root interacts with drugs, other herbals, and foods and the severity of those interactions, please use our Drug Interactions Checker to check for possible interactions.

Should I take it?

Stinging nettle belongs to a small group of perennials regarded as weeds in most places where they grow. It is very common in northwestern Europe, but nettle now invades fields, meadows, and roadsides in temperate regions of both hemispheres. Stinging nettle is covered in tiny barbs that release an irritating liquid when they are touched by animals or humans. Human skin that comes in contact with stinging nettle may be reddened and itchy for several hours and blisters may develop. In medicine, both the roots and the aerial parts (flowers, leaves, and stems) of stinging nettle are used for different conditions. Nettle root is harvested in the fall of the year and dried.

Dosage and Administration

Nettle root is available as a powder made from the dried root, or in extracts or other oral dose forms. Extracts are concentrated liquid preparations usually made by soaking chopped or mashed plant parts in a liquid such as alcohol, and then straining out the solid parts. Although dosing for nettle root varies, a common recommendation for treating BPH is 240 mg of nettle root extract per day. Commonly, nettle root is combined with other herbals such as saw palmetto, which are also believed to relieve BPH.

A tea may be prepared by soaking about 1,500 mg (1.5 grams or about one teaspoon) of the powdered root in about 5 ounces of boiling water for 10 minutes. The resulting tea should be strained before drinking it. No more than three cups of nettle root tea should be taken in a day.

Summary

Although it does not decrease prostate enlargement, nettle root appears to be somewhat effective for increasing urine output and relieving other symptoms of benign prostate hyperplasia (BPH). It may also have mild anti-inflammatory and antihypertensive effects.

Risks

Due to a lack of information about nettle root, pregnant and breast-feeding women and young children should avoid its use.

Side Effects

Side effects associated with the use of nettle root include rashes and upset stomach.

Interactions

To date, no interactions have been discovered between nettle root and drugs, herbal products, or foods.

Last Revised October 17, 2007

References

Bondarenko B, Walther C, Funk P, Schlafke S, Engelmann U. Long-term efficacy and safety of PRO 160/120 (a combination of Sabal and Urtica extract) in patients with lower urinary tract symptoms (LUTS). Phytomedicine. 2003;10(Supp IV):53-55.

Chrubasik S, Pollak S. Pain management with herbal antirheumatic drugs [Article in German]. Wiener Medizinische Wochenschrift. 2002;152(7-8):198-203.

Chrubasik JE, Roufogalis BD, Wagner H, Chrubasik S. A comprehensive review on the stinging nettle effect and efficacy profiles. Part II: urticae radix. Phytomedicine. 2007;14(7-8):568-579.

Dvorkin L, Song KY. Herbs for benign prostatic hyperplasia. Annals of Pharmacotherapy. 2002;36(9):1443-1452.

Hirano T, Homma M, Oka K. Effects of stinging nettle root extracts and their steroidal components on the Na+,K(+)-ATPase of the benign prostatic hyperplasia. Planta Med. 1994;60(1):30-33.

Jellin JM, Gregory P, Batz F, Hitchens K, et al, eds. Pharmacist's Letter/Prescriber's Letter. Natural Medicines Comprehensive Database, 3rd Edition. Stockton CA: Therapeutic Research Facility, 2000.

Koch E. Extracts from fruits of saw palmetto (Sabal serrulata) and roots of stinging nettle (Urtica dioica): viable alternatives in the medical treatment of benign prostatic hyperplasia and associated lower urinary tracts symptoms. Planta Medica. 2001;67(6):489-500.

Konrad L, Muller HH, Lenz C, Laubinger H, Aumuller G, Lichius JJ. Antiproliferative effect on human prostate cancer cells by a stinging nettle root (Urtica dioica) extract. Planta Medica. 2000;66(1):44-47.

Lopatkin N, Sivkov A, Walther C, et al. Long-term efficacy and safety of a combination of sabal and urtica extract for lower urinary tract symptoms--a placebo-controlled, double-blind, multicenter trial. World Journal of Urology. 2005;23(2):139-146.

Lichius JJ, Lenz C, Lindemann P, Muller HH, Aumuller G, Konrad L. Antiproliferative effect of a polysaccharide fraction of a 20% methanolic extract of stinging nettle roots upon epithelial cells of the human prostate (LNCaP).Pharmazie. 1999;54(10):768-771.

Lichius JJ, Muth C. The inhibiting effects of Urtica dioica root extracts on experimentally induced prostatic hyperplasia in the mouse. Planta Medica. 1997;63(4):307-310.

Lichius JJ, Renneberg H, Blaschek W, Aumuller G, Muth C. The inhibiting effects of components of stinging nettle roots on experimentally induced prostatic hyperplasia in mice. Planta Medica. 1999;65(7):666-668.

Schottner M, Gansser D, Spiteller G. Lignans from the roots of Urtica dioica and their metabolites bind to human sex hormone binding globulin (SHBG). Planta Medica. 1997;63(6):529-532.

Sokeland J. Combined sabal and urtica extract compared with finasteride in men with benign prostatic hyperplasia: analysis of prostate volume and therapeutic outcome. British Journal of Urology International. 2000;86(4):439-442.

Taylor L. Nettles. Raintree Nutrition Tropical Plant Database. Updated February 21, 2006. Available at: http://www.rain-tree.com/nettles.htm. Accessed June 2, 2006.

Testai L, Chericoni S, Calderone V, Nencioni G, Nieri P, Morelli I, Martinotti E. Cardiovascular effects of Urtica dioica L. (Urticaceae) roots extracts: in vitro and in vivo pharmacological studies. Journal of Ethnopharmacology. 2002;81(1):105-109.

Last Revised October 17, 2007

Note: The above information is not intended to replace the advice of your physician, pharmacist, or other healthcare professional. It is not meant to indicate that the use of the product is safe, appropriate, or effective for you.

In general, herbal products are not subject to review or approval by the U.S. Food and Drug Administration (FDA). They are not required to be standardized, meaning that the amounts of active ingredients or contaminants they contain may vary between brands or between different batches of the same brand. Not all of the risks, side effects, or interactions associated with the use of herbal products are known because few reliable studies of their use in humans have been done.

This information is provided for your education only. Please share this information with your healthcare provider and be sure that you talk to your doctor and pharmacist about all the prescription and non-prescription medicines you take before you begin to use any herbal product.

Back