Stinging nettle (Urtica dioica and the closely related Urtica urens) has a long medicinal history. In medieval Europe, it was used as a diuretic (to rid the body of excess water) and to treat joint pain.
Stinging nettle has fine hairs on the leaves and stems that contain 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 a painful area of the body, they can actually decrease the original pain. Scientists think nettle does this by reducing levels of inflammatory chemicals in the body, and by interfering with the way the body transmits pain signals.
General Uses
Stinging nettle has been used for hundreds of years to treat painful 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 hay fever (allergic rhinitis), or in compresses or creams for treating joint pain, sprains and strains, tendonitis, and insect bites.
Benign Prostatic Hyperplasia (BPH)
Stinging nettle root is used widely in Europe to treat BPH. Studies in people suggest that stinging nettle, in combination with other herbs (especially saw palmetto), may be effective at relieving symptoms such as reduced urinary flow, incomplete emptying of the bladder, post urination dripping, and the constant urge to urinate. These symptoms are caused by 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. Scientists aren't sure why nettle root reduces symptoms; it may be because it contains chemicals that affect hormones (including testosterone and estrogen), or because it acts directly on prostate cells. It is important to work with a doctor to treat BPH, and to make sure you have a proper diagnosis to rule out prostate cancer.
Osteoarthritis
The leaves and stems of nettle have been used historically to treat arthritis and for sore muscles. Studies have been small and not conclusive, but they do suggest that some people find relief from joint pain by applying nettle leaf topically to the painful area. A few other studies show that taking an oral extract of stinging nettle, along with nonsteroidal anti-inflammatory drugs (NSAIDs), allowed people to reduce their NSAID dose.
Hay fever
One preliminary human study suggested that nettle capsules helped reduce sneezing and itching in people with hay fever. Researchers think that may be due to nettle's ability to reduce the amount of histamine the body produces in response to an allergen. More studies are needed to confirm nettle's antihistamine properties, however. Some doctors recommend taking a freeze-dried preparation of stinging nettle well before hay fever season starts.
Other
Some preliminary animal studies indicate that nettle may lower blood sugar and blood pressure, but there is not enough evidence to say whether this is also true in humans.
Plant Description:
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, this herbaceous shrub grows all over the world today. Stinging nettle grows well in nitrogen-rich soil, blooms between June and September, and usually reaches 2 - 4 feet high.
Stems are upright and rigid. The leaves are heart-shaped, finely toothed, and tapered at the ends, and flowers are yellow or pink. The entire plant is covered with tiny stiff hairs, mostly on the underside of the leaves and stem, that release stinging chemicals when touched.
What's It Made Of?:
Stinging nettle products are usually made from the leaves and stems, and sometimes the roots. Root preparations are used to relieve symptoms of BPH.
Available Forms:
Stinging nettle is available as dried leaf, freeze-dried leaf, extract, capsules, and as root tincture (a solution of the herb in alcohol). The root appears to have different pharmacological effects than the leaves.
How to Take It:
Pediatric
Although available in many combination formulas to treat colds, asthma, and allergies in children, a specific safe and effective dose for children has not yet been established. Talk to your doctor before giving stinging nettle to a child, so the doctor can determine the proper dose.
Adult
- Tea: prepare a cup by pouring 2/3 cup of boiling water over 3 - 4 tsp of dried leaves or dried root and steeping for 3 - 5 minutes. Drink 3 - 4 cups per day. You can also make an infusion with fresh nettle leaves. Always drink additional water along with the tea.
- Dried leaf: 2 - 4 grams, 3 times a day
- Fluid extract (root,1:1): 1.5 mL, 3 - 4 times daily
- Fluid extract (leaf, 1:1): 2 - 5 mL 3 times daily
- Tincture (root, 1:5): 1 - 4 mL 3 - 4 times daily
- Creams: use as directed
Precautions:
The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and can interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care provider.
Stinging nettle is generally considered safe when used as directed. Occasional side effects include mild stomach upset, fluid retention, and hives or rash (mainly from topical use). It is important to be careful when handling the nettle plant because touching it can cause an allergic rash. Stinging nettle should never be applied to an open wound.
Because nettle can alter the menstrual cycle and may contribute to miscarriage, pregnant women should not use nettle.
Do not self-treat with nettle for BPH; see your doctor to receive a diagnosis and to rule out prostate cancer.
Possible Interactions:
Antiplatelet and anticoagulant drugs (blood-thinners) -- Stinging nettle may affect the blood's ability to clot, and could interfere with blood-thinning drugs, including:
- Warfarin (Coumadin)
- Clopidogrel (Plavix)
- Aspirin
Drugs for high blood pressure -- Stinging nettle may lower blood pressure, so it could make the effects of these drugs stronger:
- ACE inhibitors: Captpril (Capoten), Elaropril (Vasotec), lisinopril (Zestril), fosinopril (Monopril)
- Beta blockers: Atenolol (Tenormin), metoprolol (Lopressor, Toprol XL), propranolol (Induran)
- Calcium channel blockers: Nifedipine (Procardia), amlodipine (Norvasc), verapamil (Calan, Isoptin)
Diuretics (water pills) -- Because stinging nettle can act as a diuretic, it can increase the effects of these drugs, raising the risk of dehydration:
- Furosemide (Lasix)
- Hydrocholorothiazide
Drugs for diabetes -- Stinging nettle may lower blood sugar, so it could make the effects of these drugs stronger, raising the risk of hypoglycemia (low blood sugar).
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, an NSAID. Although the effect can reduce pain, talk to your doctor before taking or using stinging nettle if you also take NSAIDs.
Alternative Names:
Nettle; Urtica dioica; Urtica urens
Recipes:
Clean and chop nettles wearing rubber gloves. Once you have cooked them a little, the stingers are deactivated, and the plant becomes wonderfully edible.
Nettles have a bad reputation as an unpleasant-tasting survival food in some circles. That's because people don't know how to prepare them. They often boil them, which is awful. Nettle leaves are good simmered in soups 5-10 minutes, but my favorite method is the waterless steaming method.
I enjoy nettles as a vegetable side-dish with rice and beans. Sometimes I make creamed nettles more satisfying than creamed spinach. Because nettles have the richest, hardiest taste of any green, I often combine them with lighter ingredients, such as celery, zucchini, lemon juice, or tomato sauce.
I also dry nettles for winter use and tea. I frequently sip on warm nettle tea. It doesn't taste like a normal tea bitter, spicy, minty or lemony. It is more like a strong stock of a rich, deep, green plant essence, and it's one of the most nourishing drinks of all. Whenever I feel run down, tired, or even irritable, I think of making myself some.
I could list a bunch of recipes, but instead I am going to simply tell you to find any recipe you like that calls for greens, such as spinach or kale. Then, replace those greens with nettles.
Get out your favorite soup, stew, quiche, lasagna, pesto or even spanakopita recipe, and replace the greens in the recipe with nettles.
Heck, you can simply steam nettles and serve them as a delicious side dish. Sprinkling some Parmesan cheese on top is really nice.
What about the stings?
Good question. Definitely use gloves to transport the nettles to your pan or pot, but as soon as it begins to cook, the sting goes away. The sting quickly dissipates once you steam or cook it.
If stung look for jewelweed it cures the rash. Plantain and dock also work. "Nettle in, dock out!," say the English. Surprisingly some people actually find nettle stings invigorating, and use them to wake up the body.
How do I pick nettles?
Collect nettle leaves before they flower in spring. They may be bad for the kidneys after they flower. New nettles come up in the fall, and you can pick them before they're killed by frost.
Collect them using work gloves, and wear a long-sleeved shirt. If you happen upon nettles when you have no gloves, put your hand inside a bag. The young leaves are the best part of the plant. They come off most easily if you strip them counter-intuitively, from the top down.