Nettle extract is a concentrated preparation derived from the Urtica dioica plant, commonly known as stinging nettle. This perennial herb has fine, stinging hairs on its leaves and stems, causing temporary irritation upon contact. Despite its prickly nature, stinging nettle has a long history in traditional herbal medicine. The extract is made from different parts of the plant, including the leaves, stems, or roots.
Potential Health Applications
Nettle extract may address inflammatory conditions, for joint discomfort. Its anti-inflammatory properties stem from compounds like flavonoids and polyphenols, inhibiting pro-inflammatory substances like TNF-alpha and IL-1beta, and the NF-kB pathway. Nettle extract may also reduce pain by inhibiting prostaglandins and enzymes like cyclooxygenase (COX-1, COX-2) and 5-lipoxygenase, involved in inflammation. These mechanisms suggest a role in managing symptoms associated with osteoarthritis and rheumatoid arthritis.
For men experiencing urinary issues linked to an enlarged prostate, known as benign prostatic hyperplasia (BPH), nettle root extract is explored. It may help by inhibiting the proliferation of prostate cells and modulating the binding of sex hormone-binding globulin (SHBG) to prostate cell membranes. The extract’s anti-inflammatory effects within the prostate gland may also alleviate discomfort and improve urinary flow and bladder emptying. Studies indicate that daily doses of nettle root extract, 360-600 mg, can lead to improvements in lower urinary tract symptoms.
Nettle extract may alleviate symptoms of seasonal allergies, including sneezing and itching. It may function as a natural antihistamine by influencing the release of histamine from mast cells, key in allergic reactions. Furthermore, nettle extracts have been shown to inhibit pro-inflammatory pathways, including those involving COX-1, COX-2, and hematopoietic prostaglandin D2 synthase (HPGDS), reducing allergic inflammation. While some research supports these effects, other studies have yielded mixed results regarding its direct impact on allergy symptoms compared to a placebo.
Forms and Administration
Nettle extract is available in various forms, including capsules, pills, and liquid tinctures. Topical creams and ointments are also used externally, particularly for localized discomfort. The plant part used often dictates purpose; leaf extracts are associated with anti-inflammatory and anti-allergic applications, while root extracts are utilized for prostate-related concerns.
There is no universally standardized dosage for nettle extract, as it varies by product, concentration, and specific health application. For allergic rhinitis, 600 mg of dried nettle leaf per day, often divided, has been suggested. For BPH, studies have used aqueous root extracts at around 360 mg daily for several months or methanol root extracts up to 1,200 mg daily. Follow manufacturer’s instructions or consult a healthcare professional for personalized guidance on dosage and usage.
Safety Profile and Interactions
Nettle extract is generally tolerated, with mild side effects including stomach upset, diarrhea, or sweating. Direct contact with the fresh plant’s stinging hairs causes temporary skin irritation, redness, and itching. These reactions are transient, but care should be taken with topical applications to avoid skin irritation.
Nettle extract can interact with certain medications, altering their effects. Because some parts of the nettle plant contain vitamin K, assisting in blood clotting, it may reduce the effectiveness of blood-thinning medications like warfarin, clopidogrel, and aspirin.
Caution is advised for individuals taking blood pressure medications, including ACE inhibitors, beta-blockers, or calcium channel blockers, as nettle extract may also lower blood pressure, causing an additive effect. Nettle extract may also lower blood sugar levels, increasing the risk of hypoglycemia when taken with diabetes drugs like insulin or oral medications. Furthermore, nettle possesses diuretic properties, which could enhance prescribed diuretics or affect lithium elimination.
Discussing nettle extract use with a healthcare provider is prudent due to potential interactions, especially if currently taking other medications. Pregnant or breastfeeding individuals are generally advised to avoid nettle extract due to limited safety research and its potential to stimulate uterine contractions or cause allergic reactions in breastfed infants if applied topically.