Scientific Name: Yarrow
Other Names: Achillea, Achillea millefolium, Bloodwort, Green Arrow, Milfoil, Nosebleed Plant, Staunch Weed, Thousand-Leaf, Wound Wort, Yarroway

Who is this for?

Uses

Even though the use of yarrow has declined in recent years, it contains a number of chemicals with distinctive medicinal effects. When taken by mouth, for example, chemicals called flavonoids in yarrow are known to promote gastrointestinal (GI) secretions—including bile, saliva, and stomach acid. Both appetite and digestion may be improved by increased GI secretions. Flavonoids and other components of yarrow may also relax the smooth muscles in the GI tract, possibly reducing stomach cramps. Muscles in the uterus may also relax, which may relieve menstrual cramps, reduce heavy menstrual bleeding, and regulate menstrual periods. Because additional chemicals in yarrow may be anti-inflammatory, it may also help to alleviate pain. Taking yarrow may slightly reduce high blood pressure due to its mild diuretic (urine producing) effect. It also may promote sweating. Therefore, it has been used to treat fevers. However, more studies are needed to evaluate these all effects.

Topically, yarrow acts as an astringent, which neans that it shrinks and tightens the top layers of skin or mucous membranes, thereby reducing secretions, relieving irritation, and improving tissue firmness. Traditionally, yarrow’s astringent effect has been used to lessen bleeding from injuries. More recently, it has been used as an external wash to stop minor bleeding from hemorrhoids and to shrink hemorrhoids and varicose veins. Its slight antibacterial and anti-inflammatory properties may also help prevent infections resulting from injury to the skin.

Yarrow’s ability to relax the muscles in the uterus may cause miscarriage. Additionally, in a study of laboratory animals, mothers given yarrow during pregnancy tended to have babies of lower than average weight. While no decreases in birth weight have been attributed to taking yarrow among humans, underweight human babies have a higher risk of breathing, gastrointestinal, heart, or other problems than babies who are in normal weight ranges at birth. Both these potential effects make yarrow inappropriate for use by women who are pregnant.

Precautions

Yarrow belongs to the same family of plants that includes chrysanthemums, daisies, and ragweed. Individuals who are sensitive to any of these types of plants may also be sensitive to either oral or topical yarrow.

Both oral and topical yarrow can make unprotected skin more sensitive to sunlight or artificial light such as is used in sun tanning parlors. Individuals who use yarrow should not only limit the amount of time spent in sunlight, they should be sure to use sunscreen, as well.

Not enough is known about how yarrow might affect an infant to recommend its use while breast-feeding.

What side effects should I watch for?

Few side effects have been reported from using recommended doses of yarrow either topically or orally. In laboratory animals, doses that were 10 times the usual dose caused:

• Diarrhea
• Drowsiness
• Excessive urination

What interactions should I watch for?

Prescription Drugs

Yarrow may increase the production of stomach acid, potentially interfering with Histamine-2 (H-2) receptor blockers such as:

• cimetidine (Tagamet)
• famotidine (Pepcid)
• nizatidine (Axid)
• ranitidine (Zantac)

• Nexium
• omeprazole (Prilosec)
• Prevacid
• Protonix

Yarrow may increase the time blood needs to clot. When it is taken with antiplatelet or anticoagulant drugs, the effect of the drug may be increased, resulting in uncontrolled bleeding.

• Antiplatelets include clopidogrel and Ticlid
• Anticoagulants include heparin and warfarin

Due to its mild ability to lower blood pressure, yarrow is believed to increase the effects of drugs that also lower blood pressure. Some blood pressure-lowering drugs are:

• ACE inhibitors such as captopril, enalapril, fosinopril, and lisinopril
• Beta blockers such as atenolol, metoprolol, and propranolol
• Calcium channel blockers such as amlodipine, nifedipine, and verapamil
• Diuretics such as Dyazide, furosemide, and hydrochlorothiazide

When yarrow is used with prescription drugs that promote sleepiness, the effects of the drug may be exaggerated, resulting in sedation or mental impairment. Prescription drugs that can cause sleepiness include:

• Anticonvulsants such as carbamazepine, phenytoin and valproic acid
• Barbiturates such as phenobarbital
• Benzodiazepines such as alprazolam and diazepam
• Drugs for insomnia such as Rozerem, Sonata, and zolpidem
• Tricyclic antidepressants such as amitriptyline, amoxapine, doxepin and nortriptyline

Non-prescription Drugs

The possibility that yarrow can increase the production of stomach acid could interfere with the effectiveness of antacids and over-the-counter medications such as Pepcid AC, Prilosec OTC, and Zantac AR.

Yarrow can decrease the ability of blood to clot after an injury. Aspirin can also delay clotting, so yarrow should not be taken with aspirin.

The sleep-producing effects of over-the-counter products containing diphenhydramine or doxylamine may be enhanced by taking yarrow at the same time. Diphenhydramine or doxylamine is contained in many non-prescription sleeping pills as well as in some cough and cold products, therefore caution should be used when taking these medications with yarrow because excessive drowsiness may result.

Herbal Products

Theoretically, if yarrow is used with other herbs that affect blood clotting, bleeding may occur. Some of the most common herbal products that might inhibit blood clotting are:

• Danshen
• Devil's Claw
• Eleuthero
• Garlic
• Ginger (in high amounts)
• Ginkgo
• Horse Chestnut
• Panax Ginseng
• Papain
• Red Clover
• Saw Palmetto

Yarrow may cause excessive sedation if it is taken with other potentially sedating herbs such as:

• Catnip
• Hops
• Kava
• St. John's wort
• Valerian

Foods

No interactions between yarrow and foods have been reported, but drinking alcohol at the same time as using yarrow by mouth may result in increased drowsiness.

Some interactions between herbal products and medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals. For specific information on how yarrow interacts with drugs, other herbals, and foods and the severity of those interactions, please use our Drug Interactions Checker to check for possible interactions.

Should I take it?

Believed to have originated in the cool parts of Asia and Europe, yarrow was known to ancient Greek warriors as long as 3,000 years ago. At that time, its fresh leaves and flowers were eaten raw or cooked and a tea-like drink was made from dried yarrow leaves. The “aerial” or above ground parts of yarrow (flowers, leaves, and stems) were dried and ground into a type of snuff. Medicinally, yarrow’s fresh leaves were packed onto wounds to stop bleeding. It was also brewed into a tea that was taken by mouth to fight fevers, treat gastrointestinal conditions, lessen heavy menstrual bleeding, and improve circulation. Fresh leaves were chewed to relieve toothaches or packed into the nose to stop nosebleeds.

Now growing wild in most parts of the world, yarrow includes many perennial species in the same family of plants as daisies. Usually under 3 feet in height, yarrow plants thrive in poor soil. They spread rapidly–even crowding out crops, if they are not controlled with herbicide. Yarrow is easily distinguished from other plants by its feathery leaves and its clumps of white, yellowish, pink, lavender, or red flowers that begin blooming in early summer and keep blooming until a hard frost. In addition to its role in herbal medicine, yarrow is used in manufacturing. It is included in some cosmetics and shampoos. Yarrow flowers provide yellow and greenish dyes. Oil distilled from yarrow leaves may be used to repel insects in some parts of the world. Additionally, yarrow is sometimes added to beer and its young leaves may be included in salads for a slightly bitter taste.

Dosage and Administration

Although oral dosing recommendations for yarrow are not consistent, a tea may be made by boiling one teaspoon or 2 teaspoons of dried yarrow in about 8 ounces of water for 5 minutes and then straining out the solid particles. Yarrow tea may be taken up to three times a day. Yarrow is also available commercially in capsules, extracts, and tinctures. Extracts are concentrated liquid preparations usually made by soaking chopped or mashed plant parts in a liquid such as alcohol, and then straining out the solid parts. Tinctures are less concentrated than extracts, but they are prepared in similar ways. Individuals who decide to use yarrow should follow the directions on the label of the package that is purchased.

For external use, 100,000 mg (100 grams or about 3 ounces) of dried yarrow flowers, leaves, and stems may be soaked in 5 gallons of warm water overnight. The solid particles should be removed before use, and the resulting liquid should be refrigerated or tightly capped to prevent contamination. It should be used within a few days as a wash or poultice. A poultice is usually a soft cloth that has been soaked in a medication, possibly heated, and applied to an aching or injured area of skin surface.

Summary

Currently, yarrow may be taken by mouth to relieve gastrointestinal complaints—including stomach cramps–as well as menstrual cramps. It may have some ability to reduce blood pressure and relieve fever. In addition, it may be applied to stop bleeding from minor injuries.

Risks

Due to its relaxation of the uterus, yarrow may cause miscarriages for pregnant women. Women who are breast-feeding should also avoid using yarrow because too little is known about its possible effects on infants. It may cause skin to be more sensitive to light and individuals with allergies to plants in the daisy family may also be allergic to yarrow.

Side Effects

In very high doses, yarrow may cause diarrhea, drowsiness, or excessive urination.

Interactions

Chemicals in yarrow may interfere with the effects of prescription drugs, non-prescription drugs, and herbals that reduce stomach acid. It may increase the effects of agents that lower blood pressure, lessen blood clotting, and produce sleepiness.

Last Revised June 1, 2007

References

Anon. Final report on the safety assessment of yarrow (Achillea millefolium) extract. International Journal of Toxicology. 2001;20(Suppl 2):79-84.

Anon: Yarrow. In: DerMarderosian A, Beutler JA, eds. Facts and Comparisons: The Review of Natural Products. St. Louis, MO, Facts and Comparisons. April 1998.

Asgary S, Naderi GH, Sarrafzadegan N, Mohammadifard N, Mostafavi S, Vakili R. Antihypertensive and antihyperlipidemic effects of Achillea wilhelmsii. Drugs under Experimental and Clinical Research. 2000;26(3):89-93.

Benedek B, Geisz N, Jäger W, Thalhammer T, Kopp B. Choleretic effects of yarrow (Achillea millefolium s.l.) in the isolated perfused rat liver. Phytomedicine. Epublished ahead of print. November 19, 2005.

Bezic N, Skocibusic M, Dunkic V, Radonic A. Composition and antimicrobial activity of Achillea clavennae L. essential oil. Phytotherapy Research. 2003;17(9):1037-1040.

Boswell-Ruys CL, Ritchie HE, Brown-Woodman PD. Preliminary screening study of reproductive outcomes after exposure to yarrow in the pregnant rat. Birth Defects Research. Part B. Developmental and Reproductive Toxicology. 2003;68(5):416-420.

Candan F, Unlu M, Tepe B, et al. Antioxidant and antimicrobial activity of the essential oil and methanol extracts of Achillea millefolium subsp. millefolium Afan. (Asteraceae). Journal of Ethnopharmacology. 2003;87(2-3):215-220.

Cavalcanti AM, Baggio CH, Freitas CS, et al. Safety and antiulcer efficacy studies of Achillea millefolium L. after chronic treatment in Wistar rats. Journal of Ethnopharmacology. Epublished ahead of print. March 22, 2006.

Chandler RF, Hooper SN, Hooper DL, Jamieson WD, Flinn CG, Safe LM. Herbal remedies of the Maritime Indians: sterols and triterpenes of Achillea millefolium L. (Yarrow). Journal of Pharmaceutical Sciences. 1982;71(6):690-693.

Dalsenter PR, Cavalcanti AM, Andrade AJ, Araujo SL, Marques MC. Reproductive evaluation of aqueous crude extract of Achillea millefolium L. (Asteraceae) in Wistar rats. Reproductive Toxicology. 2004;18(6):819-823.

Felter HW, Lloyd JU. King’s American Dispensatory. Eighteenth Edition. Third Revision. Cincinnati, Ohio. Ohio Valley Co. 1898. Available at: http://www.ibiblio.org/herbmed/eclectic/kings/intro.html. Accessed: July 23, 2003.

Hausen BM. A 6-year experience with compositae mix. American Journal of Contact Dermatology. 1996;7(2):94-99.

Jaenson TG, Pålsson K, Borg-Karlson AK. Evaluation of extracts and oils of mosquito (Diptera: Culicidae) repellent plants from Sweden and Guinea-Bissau. Journal of Medical Entomology. 2006;43(1):113-119.

Jellin JM, Gregory P, Batz F, Hitchens K, et al, eds. Pharmacist's Letter/Prescriber's Letter. Natural Medicines Comprehensive Database, 3rd Edition. Stockton CA: Therapeutic Research Facility, 2000.

Karamenderes C, Apaydin S. Antispasmodic effect of Achillea nobilis L. subsp. sipylea (O. Schwarz) Bassler on the rat isolated duodenum. Journal of Ethnopharmacology. 2003;84(2-3):175-179.

Maswadeh HM, Semreen MH, Naddaf AR. Anti-inflammatory activity of Achillea and Ruscus topical gel on carrageenan-induced paw edema in rats. Acta Pol Pharm. 2006;63(4):277-280.

Natural Medicines Comprehensive Database, Online Edition. Pharmacist's Letter/Prescriber's Letter. Stockton CA: Therapeutic Research Facility, 2006. Available at: http://www.pharmacistsletter.com/(S(ulqz3s45omt3ag55um4kj345))/home.aspx?li=1&st=1&cs=&s=ND.

Paulsen E, Andersen KE, Hausen BM. Sensitization and cross-reaction patterns in Danish Compositae-allergic patients. Contact Dermatitis. 2001;45(4):197-204.

Peirce A. The American Pharmaceutical Association Practical Guide to Natural Medicines. New York: Stonesong Press; 1999.

Plants for a Future Database. Achillea millefolium. No date given. Available at: http://www.ibiblio.org/pfaf/cgi-bin/arr_html?Achillea+millefolium. Accessed July 23, 2003.

Santoro GF, Cardoso MG, Guimaraes LG, Mendonca LZ, Soares MJ. Trypanosoma cruzi: Activity of essential oils from Achillea millefolium L., Syzygium aromaticum L. and Ocimum basilicum L. on epimastigotes and trypomastigotes. Experimental Parasitology. Epublished ahead of print. February 1, 2007.

Simon JE, Chadwick AF, Craker LE. Herbs: An Indexed Bibliography. Hamden, CT: Archon Books; 1984.

Sokmen A, Sokmen M, Daferera D, et al. The in vitro antioxidant and antimicrobial activities of the essential oil and methanol extracts of Achillea biebersteini Afan. (Asteraceae). Phytotherapy Research. 2004;18(6):451-456.

Stojanoviã G, Raduloviã N, Hashimoto T, Paliã R. In vitro antimicrobial activity of extracts of four Achillea species: the composition of Achillea clavennae L. (Asteraceae) extract. Journal of Ethnopharmacology. 2005;101(1-3):185-190.

Sokmen A, Vardar-Unlu G, Polissiou M, Daferera D, Sokmen M, Donmez E. Antimicrobial activity of essential oil and methanol extracts of Achillea sintenisii Hub. Mor. (Asteraceae). Phytotherapy Research. 2003;17(9):1005-1010.

Tewari JP, Srivastava MC, Bajpai JL. Phytopharmacologic studies of Achillea millefolium Linn. Indian Journal of Medical Science. 1974;28(8):331-336.

Unlu M, Daferera D, Donmez E, Polissiou M, Tepe B, Sokmen A. Compositions and the in vitro antimicrobial activities of the essential oils of Achillea setacea and Achillea teretifolia (Compositae). Journal of Ethnopharmacology. 2002;83(1-2):117-121.

Yaeesh S, Jamal Q, Khan AU, Gilani AH. Studies on hepatoprotective, antispasmodic and calcium antagonist activities of the aqueous-methanol extract of Achillea millefolium. Phytotherapy Research. 2006;20(7):546-551.

Last Revised June 1, 2007

Note: The above information is not intended to replace the advice of your physician, pharmacist, or other healthcare professional. It is not meant to indicate that the use of the product is safe, appropriate, or effective for you.

In general, herbal products are not subject to review or approval by the U.S. Food and Drug Administration (FDA). They are not required to be standardized, meaning that the amounts of active ingredients or contaminants they contain may vary between brands or between different batches of the same brand. Not all of the risks, side effects, or interactions associated with the use of herbal products are known because few reliable studies of their use in humans have been done.

This information is provided for your education only. Please share this information with your healthcare provider and be sure that you talk to your doctor and pharmacist about all the prescription and non-prescription medicines you take before you begin to use any herbal product.

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