How does stinging nettle work to reduce inflammation and allergies?

Nettle contains several bioactive compounds that modulate inflammatory pathways. Research suggests it inhibits cyclooxygenase and lipoxygenase enzymes, reducing prostaglandin and leukotriene production (Evidence Level B). Additionally, nettle appears to block histamine receptors and may reduce the release of inflammatory cytokines. These mechanisms help explain its traditional use for seasonal allergies and joint inflammation. The presence of scopoletin and beta-sitosterol contributes to these anti-inflammatory effects.

Can I take stinging nettle with blood pressure medication or diuretics?

Nettle has natural diuretic properties and may enhance the effects of antihypertensive medications and prescription diuretics (Evidence Level C). This combination could potentially cause blood pressure to drop too low or lead to dehydration and electrolyte imbalances. Patients taking lithium should avoid nettle entirely, as increased diuresis can raise lithium to toxic levels. Always consult a healthcare provider before combining nettle with any cardiovascular medications.

What is the recommended dosage for stinging nettle leaf?

The standard adult dosage for nettle leaf is 300-600mg of freeze-dried extract taken 2-3 times daily (Evidence Level B). For tea, steep 1-2 teaspoons of dried leaf in hot water for 10-15 minutes, consuming 2-4 cups daily. For benign prostatic hyperplasia, nettle root extracts of 120-240mg daily have been studied. Start with lower doses to assess tolerance, and always follow product-specific recommendations from reputable manufacturers.

Is stinging nettle safe to take during pregnancy?

Nettle is considered unsafe during pregnancy and should be avoided (Evidence Level D). The herb may stimulate uterine contractions and has been used traditionally to induce menstruation, posing a potential miscarriage risk. While nettle leaf is sometimes recommended as a nutritive prenatal tonic by some herbalists, the safety data is insufficient. Pregnant individuals should consult a qualified healthcare provider before using any herbal supplements. Breastfeeding women should also exercise caution due to limited safety data.

Does stinging nettle really help with joint pain and arthritis?

Clinical research suggests nettle may provide relief for osteoarthritis and joint pain (Evidence Level B). Studies indicate that topical application of fresh nettle leaves can reduce pain, likely through the counter-irritant effect of formic acid. Oral supplementation with nettle has shown modest benefits in reducing osteoarthritis symptoms, particularly when combined with conventional treatments. The anti-inflammatory compounds, including beta-sitosterol, may help modulate inflammatory pathways involved in joint degradation.

Nettle (Urtica dioica)

What is a herb–drug interaction?

A herb–drug interaction happens when a plant or supplement changes how a medication works in your body — making it stronger, weaker, or more likely to cause harm. Herbs contain active compounds that can speed up or slow down the enzymes and transporters your body uses to process drugs.

Why it matters

St. John's Wort can make birth control, antidepressants, and blood thinners less effective.

Garlic can increase bleeding risk with warfarin and other blood thinners (also ginkgo, ginger, and turmeric).

Kava can amplify sedation when taken with anxiety or sleep medications (also valerian).

The risk is highest for older adults, anyone taking several medications, and people with chronic conditions.

Always tell your doctor and pharmacist about every herb and supplement you take — and check below before combining.

Known Drug Interactions (2)

1 Moderate1 Mild

Drug	Severity	Description
Lithium	Moderate	Nettle's diuretic effect may increase lithium concentration by reducing lithium excretion, risking toxicity.
Antihypertensives	Mild	Nettle may have mild blood pressure-lowering effects that add to antihypertensive medications.

This list reflects a curated subset of documented interactions and is not exhaustive. The absence of a drug here is not proof that it is safe to combine. Always confirm with a pharmacist or healthcare provider.

PubMed-compiled information sheet

This sheet was compiled from PubMed (NIH) abstracts using AI assistance. Every factual claim is cited to a real PubMed article (see the source list). It has not yet been human-reviewed — confirm with a healthcare provider before use.

Compiled from 28 PubMed articles · model: gemma4:31b

Summary

Stinging nettle (Urtica dioica L.) is a wild herbaceous perennial plant with nutritional and medicinal properties used globally [PMID:35800714, PMID:36014458].

Background

Urtica dioica is a common, multi-purpose herbaceous perennial blooming plant found in Europe, Asia, North Africa, and North America [PMID:35800714, PMID:36014458]. It is often considered a weed due to its invasive capacity and fast growth, though it is suitable for cultivation as a beneficial crop for food, medicine, and fiber production [PMID:39861633, PMID:35744347].

Traditional uses

Traditionally, the roots are used to treat mictional difficulties associated with benign prostatic hyperplasia, while the leaves are used for arthritis, rheumatism, and allergic rhinitis [PMID:35800714]. It has also been used as a postpartum tonic for treating anemia and as a purported galactogogue in nursing mothers [PMID:37011125].

Active compounds

Bioactive constituents include flavonoids (such as rutin and kaempferol), phenolic acids (caffeoylmalic, chlorogenic, neochlorogenic, and cichoric acids), carotenoids, fatty acids, and vitamins [PMID:36014458, PMID:36771171]. Roots are specifically rich in phytosterols, lignans, coumarins, sugars, and lectins (Urtica dioica agglutinin) [PMID:39861633, PMID:31717749].

Mechanism of action

Potential mechanisms include the inhibition of HMGCoA reductase and amelioration of lipid peroxidation via antioxidant effects [PMID:35911652]. Quercetin is noted for decreasing total cholesterol [PMID:35911652]. Hypothetically, galactogogue effects may result from the binding of sex hormone-binding globulin by polar extracts, leading to elevated serum estrogen levels [PMID:37011125]. Leaf extracts may act as P2-purinoceptor antagonists [PMID:35900970].

Clinical evidence

Evidence CBenign Prostatic Hyperplasia

Root extracts are purported to relieve urinary symptoms [PMID:37011125] and prevent some effects of prostatic hyperplasia [PMID:31163183].

Evidence CInflammatory Conditions (Arthritis/Rheumatism)

Leaves are used to treat arthritis and rheumatism [PMID:35800714]; leaf extracts are used as anti-inflammatory remedies for rheumatoid arthritis [PMID:31163183].

Evidence CMetabolic Syndrome/Hypertension

Traditionally used to control cardiovascular disorders and hypertension; suggested mechanisms involve alterations in potassium and calcium channels [PMID:31163183, PMID:35911652].

Evidence DMale Fertility

In mouse mating studies, daily oral administration of 50 mg of leaf extract reduced male fertility by 53% [PMID:35900970].

Pregnancy & lactation

Preparations have been used orally by nursing mothers as a postpartum tonic for anemia and as a galactogogue [PMID:37011125].

Evidence summary

The evidence is primarily based on reviews and traditional use (Level C), with some animal-model data (Level D) regarding fertility and neuroprotection. There is a lack of high-level clinical trial data (Level A/B) in the provided abstracts.

PubMed sources

1.PMID: 35800714 (2022) — Nutritional and pharmacological importance of stinging nettle (Urtica dioica L.): A review. · Heliyon
2.PMID: 36014458 (2022) — Stinging Nettle (Urtica dioica L.): Nutritional Composition, Bioactive Compounds, and Food Functional Properties. · Molecules (Basel, Switzerland)
3.PMID: 37011125 (2012) — Herbal Teas and their Health Benefits: A Scoping Review. · Plant foods for human nutrition (Dordrecht, Netherlands)
4.PMID: 14744424 (2003) — Stinging nettle dermatitis. · American journal of contact dermatitis : official journal of the American Contact Dermatitis Society
5.PMID: 29632497 (2018) — Urtica dioica (Stinging Nettle): A Neglected Plant With Emerging Growth Promoter/Immunostimulant Properties for Farmed Fish.

Nettle

Sources & Citations

Nettle Leaf

Roman Nettle

Swedish Nettle Herb

⚠️ Not Recommended During Pregnancy or Nursing

2 Known Drug Interactions — Some May Be Serious

Contraindications

Possible Side Effects

What is a herb–drug interaction?

Known Drug Interactions (2)

Summary

Background

Traditional uses

Active compounds

Mechanism of action

Clinical evidence

Pregnancy & lactation

Evidence summary

PubMed sources

Government sources

Nettle

Sources & Citations

Related Herbs

Nettle Leaf

Roman Nettle

Swedish Nettle Herb

⚠️ Not Recommended During Pregnancy or Nursing

2 Known Drug Interactions — Some May Be Serious

Contraindications

Possible Side Effects

What is a herb–drug interaction?

Known Drug Interactions (2)

Summary

Background

Traditional uses

Active compounds

Mechanism of action

Clinical evidence

Pregnancy & lactation

Evidence summary

PubMed sources

Government sources