Urtica includes about 45 species of herbs, including 4 in North America, which are well known for the painful stinging hairs borne on their stems and leaves. Although often considered to be undesirable weeds, nettles have many traditional uses. Stem fibers were used to make cordage or cloth. Leaves are edible when boiled, as the irritant substances are destroyed by heat, and are used to make soups or vitamin-rich teas. The root is used medicinally for conditions including age-related urinary symptoms (benign prostatic hyperplasia). The live plant is also frequently used for joint pain in a treatment called urtication, which involves deliberately stinging the skin over painful areas and is thought to reduce joint inflammation.

Nettle root contains beta-sitosterol, which is the primary active ingredient in several herbs used to treat BPH, including saw palmetto or ?sabal? (whose efficacy has been well documented in multiple clinical trials), pygeum, and pumpkin seed. Most clinical studies have used products that combined nettle root with saw palmetto or pygeum; these have consistently shown significant benefits and excellent safety. There has been one small human trial of urtication for arthritic pain in thumb and finger joints, which showed significant reductions in pain and disability (and it feels so good when you stop!).

Selected References

Ball, P.W., revised by D. V. Geltman. 1993. Urtica. Pp. 79-80 in: Tutin et al., eds., Flora Europaea ed. 2, vol. 1. Cambridge University Press: Cambridge.

Boufford DE. 1997. Urticaceae. Pp. 400-413 in: Flora of North America Editorial Committee, eds. Flora of North America, vol. 3. Oxford University Press: New York.

Corsi, G., F. Garbari, and F. Maffei. 1999. Il genere Urtica L. (Urticaceae) in Italia. Revisione biosistematica. Webbia 53:193-239.

Lopatkin, N., A. Sivkov, C. Walther, S. Schlafke, A. Medvedev, J. Avdeichuk, G. Golubev, K. Melink, N. Elenberger, and U. Engelmann. 2005. 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 J. Urol. 23:139-146.

Miller, N. G. 1971. The genera of the Urticaceae in the southeastern United States. J. Arnold Arbor. 52:40-68.

Randall, C., H. Randall, F. Dobbs, C. Hutton, and H. Sanders. 2000. Randomized controlled trial of nettle sting for treatment of base-of-thumb pain. J. R. Soc. Med. 93:305-309.

Sokeland, J. 2000. Combined sabal and urtica extract compared with finasteride in men with benign prostatic hyperplasia: analysis of prostate volume and therapeutic outcome. BJU Int. 86: 439-442.

Woodland, D. W. 1982. Biosystematics of the perennial North American taxa of Urtica. II. Taxonomy. Syst. Bot. 7:282-290.

Woodland, D. W., I. J. Bassett, C. Crompton, and S. Forget. 1982. Biosystematics of the perennial North American taxa of Urtica. I. Chromosome number, hybridization and palynology. Syst. Bot. 7:269-281.