Practitioners of traditional herbal medicine have used the stinging nettle plant, or Urtica dioica, for many disorders. The plant originated in northern Europe and Asia, and now grows worldwide as a wild plant that is about 4 feet tall. Its leaves and stem are covered with tiny hairs that release stinging substances and give the plant its name. The herbaceous parts of the plant and its roots have medicinal properties that differ somewhat from each other. Discuss using nettle with your doctor to decide if it is a good choice for you.
Traditionally, nettle root is used to treat various urinary problems. Today, it is a recognized remedy for benign prostatic hyperplasia, or BPH, and, in Europe, it is used routinely as a treatment for this condition. Symptoms of BPH, including "reduced urinary flow, incomplete emptying of the bladder ... and [a] constant urge to urinate," may be relieved by nettle root, according to the University of Maryland Medical Center. Although the mechanism is not well understood, the root may improve the condition by lowering levels of testosterone, a hormone that stimulates growth of the prostate and may be responsible for its abnormal growth in BPH.
Nettle Leaves and Stems
The herbaceous parts of stinging nettle have properties that may make them useful in painful conditions such as arthritis and sore muscles. In these situations, nettle is applied topically to the painful area. Taken internally, nettle capsules may also help reduce sneezing and itching that occurs in some allergies such as hay fever, possibly by reducing the body's production of histamine in response to an allergen.
A number of clinical studies have reported that nettle root is useful in treating BPH. In one of these, published in the "Journal of Herbal Pharmacotherapy" in 2005, subjects with the disorder who took nettle root experienced a marked improvement in their symptoms compared to others who took a placebo.
Several studies have also investigated the usefulness of nettle leaves for painful conditions. In one clinical trial published in 2000 in the "Journal of the Royal Society of Medicine," subjects with arthritic thumb pain used nettle or another nonmedicinal leaf topically for one week. Those who used nettle had significant pain relief compared to the control group. In addition, in a review of several herbs published in "Alternative Medicine Reviews" in 2000, stinging nettle was judged to be useful as a possible primary therapy for seasonal allergies.
Recommendations and Precautions
Stinging nettle is available from health food stores as loose, dried leaf or as a supplement in capsules, while nettle root is available as a tincture. The dried leaf is usually taken at a dose of 2 to 4 gm, three times a day; it may be used to prepare a tea by steeping at least 3 tsp. of dried leaf in 2/3 cup of boiling water for about five minutes. The root tincture may be diluted in water, one part tincture to five parts water, and 1 to 4 ml of this dilution consumed three or four times daily. Nettle leaf and root are generally considered safe, according to the University of Maryland Medical Center, although they may cause upset stomach in some people. Do not take either preparation if you are pregnant and discuss use of nettle leaf or root with your doctor before consuming it.