Stinging nettle (Urtica dioica and the closely related Urtica urens) has a long medicinal history. In medieval Europe, diuretics and remedies for joint problems were made from stinging nettle. Healers in several traditions used the branches of stinging nettle to strike the arms or legs of paralyzed patients in order to activate their muscles. This whipping technique is also used in some healing traditions to stimulate the organs and relieve the pain of sore muscles.

The stinging hairs on nettle are sharp polished spines that contain histamine and formic acid, irritating chemicals that are released when the plant comes in contact with the skin. While the hairs, or spines, of the stinging nettle are normally very painful to the touch, when they come into contact with an area of the body that is already in pain, the chemicals can actually decrease the original pain. This is why stinging nettle is called a counterirritant. Applying juice from the stinging nettle to the skin can actually relieve painful nettle stings or insect bites.

General Uses

Stinging nettle has been used for hundreds of years to treat rheumatism (disorders of the muscles and joints), eczema, arthritis, gout, and anemia. Today, many people use it to treat urinary problems during the early stages of an enlarged prostate (called benign prostatic hyperplasia or BPH), for urinary tract infections, for kidney stones, for hay fever (allergic rhinitis), or in compresses or creams for treating joint pain, sprains and strains, tendonitis, and insect bites. In fact, some small but well designed studies are beginning to confirm that certain traditional uses have scientific validity, particularly osteoarthritis especially when used in conjunction with anti-inflammatory medications (see Possible Interactions), and BPH. Plus, recent laboratory studies are offering plausible explanations for why stinging nettles might help rheumatoid arthritis as well as several of the conditions already mentioned.

Benign Prostatic Hyperplasia (BPH)

Reports claim that as many as 80% of European men with BPH are given the option of herbal remedies for their symptoms, including saw palmetto and stinging nettle roots, rather than medication or surgery. Studies in people suggest that the root of the stinging nettle, in combination with other herbs especially saw palmetto, may be an effective treatment for BPH, relieving urinary symptoms such as reduced urinary flow, incomplete emptying of the bladder, post urination dripping, and the constant urge to urinate. These symptoms are due to the enlarged prostate gland pressing on the urethra (the tube that empties urine from the bladder). Laboratory studies have shown stinging nettle to be comparable to finasteride (a medication commonly prescribed for BPH) in slowing the growth of certain prostate cells. However, unlike finasteride, the herb does not decrease prostate size.

Other

In animal studies, nettle has been shown to relieve pain, have mild anti-inflammatory effects, and to lower blood sugar levels. Active compounds in stinging nettle may act as an expectorant (meaning that it can loosen and break up a cough) and have anti-viral properties.

Nettle may also be effective for treating certain individuals with allergic rhinitis (hay fever). This traditional use has had a lot of historical value for individuals. Early studies of people suggest that this historic use is likely scientifically valid. However, while the studies thus far have been favorable, they have not been overwhelmingly so. More research would be helpful. In the meantime, talk to your doctor about whether it is safe for you to try nettle as a possible alternative treatment during allergy season if you are prone to hay fever.

Stinging nettle is the name given to common nettle, garden nettle, and hybrids of these two plants. Originally from the colder regions of northern Europe and Asia, today this herbaceous shrub grows all over the world. Stinging nettle grows well in nitrogen-rich soil, blooms between June and September, and reaches nearly 3 feet high.

The branching stems underground multiply by themselves and have multiple shoots. The leaves are heart-shaped, finely toothed, and tapered at the ends. The entire plant is covered with tiny stinging hairs, mostly on the underside of the leaves and stem.

Stinging nettle products are usually made from the roots and/or leaves. It is thought that the flavonoids and potassium in nettle leaves are responsible for their diuretic action. Root preparations are used to relieve some of the symptoms of BPH.

Stinging nettle is available as dried leaf, as tea, and as root tincture (a tincture is a solution of the herb in alcohol). Stinging nettle can also be purchased in capsule form.

Pediatric

Although available in many combination formulas to treat colds, asthma, and allergies in children, a specific safe and effective dose for this age range has not yet been established. It is best to follow the instructions of a trained herbalist when using stinging nettles in children.

Adult

• Tea: prepare a cup by pouring 2/3 cup of boiling water over 3 to 4 tsp of dried leaves or dried root and steeping for 3 to 5 minutes. Drink three to four of these cups a day. An infusion can also be made with fresh nettle leaves. Always drink additional water along with the tea (at least 2 quarts per day).
• Dried leaf: 2 to 4 grams, three times a day
• Fluid extract (root,1:1): 1.5 mL, three to four times daily
• Fluid extract (leaf, 1:1): 2 to 5 mL three times daily
• Tincture (root, 1:5): 5 to 7.5 mL three to four times daily
• Creams: use as directed

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

Stinging nettle is generally considered safe when used as directed. Occasional side effects include mild stomach upset, fluid retention, and hives (mainly from topical use). It is important to exercise care when handling the nettle plant as contact with skin can cause result in an allergic rash, such as contact dermatitis or hives.

Because nettle can alter the menstrual cycle and may contribute to miscarriage, pregnant women should not use nettle, and lactating women should avoid excessive use of this herb.

Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)
In a scientific study of patients with acute arthritis, stewed stinging nettle leaves enhanced the anti-inflammatory effect of diclofenac, a non-steroidal anti-inflammatory medication (NSAID). Although the combination of stinging nettle and NSAIDs may be beneficial for the treatment of arthritic conditions, a knowledgeable healthcare provider should be consulted before adding this herb to an existing medication regimen.

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