Stinging Nettle - Warfarin Interaction
Herbal: Stinging Nettle
Also Known As: Urtica dioica, Urtica urens, Bichu, Common Nettle, Great Stinging Nettle, Nettle, Nettle Leaf, Nettle Seed, Nettle Worth, Nettles, Ortie, Ortiga, Small Nettle, Stinging Nettles, Urtica
Drug: Warfarin
Brand names:
Warfarin
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 18, 2025
Interaction Details
Warfarin is classified as belonging to the following category: Warfarin (Coumadin)
There is some concern that stinging nettle might decrease the effects of anticoagulant drugs such as warfarin.
Stinging nettle contains a significant amount of vitamin K. When taken in large quantities, this might interfere with the activity of warfarin.
Interaction Rating
Likelihood of Occurrence
PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
References
- Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
Stinging Nettle Overview
Stinging nettle (Urtica dioica) is a perennial flowering plant that belongs to the Urticaceae family. It is native to Europe, Asia, and North America, and is characterized by its green leaves and small, greenish-white flowers. Stinging nettle has small, stinging hairs on its leaves and stems, which can cause a painful rash when touched.
The leaves and the roots of stinging nettle have been used in traditional medicine to treat a variety of conditions such as joint pain, diabetes, enlarged prostate, anemia, and urinary tract infections. It is also used as a diuretic and to help with allergies as it contains the compound quercetin. The leaves and stems of the plant are edible and can be consumed as a vegetable, usually after boiling or steaming to remove the stinging hairs, as the plant is rich in vitamins, minerals, and antioxidants.
Warfarin Overview
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Warfarin is used to prevent blood clots from forming or growing larger in your blood and blood vessels. It is prescribed for people with certain types of irregular heartbeat, people with prosthetic (replacement or mechanical) heart valves, and people who have suffered a heart attack. Warfarin is also used to treat or prevent venous thrombosis (swelling and blood clot in a vein) and pulmonary embolism (a blood clot in the lung). Warfarin is in a class of medications called anticoagulants ('blood thinners'). It works by decreasing the clotting ability of the blood.
Stinging Nettle - More Interactions
Stinging Nettle interacts with 162 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
| Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
| Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
| Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
| Unknown | No interactions have been reported or no interaction data is currently available. |
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Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Drug descriptions are provided by MedlinePlus.
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Dr. Brian Staiger, PharmD
In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!
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