Dog Daisy
Achillea millefolium
Asteraceae; formerly Compositae
Yarrow, Common Yarrow, Milfoil, Thousand-Leaf, Thousand-Seal, Soldier’s Woundwort, Soldier’s Wound Wort, Woundwort, Bloodwort, Nosebleed, Nosebleed Plant, Staunchweed, Carpenter’s Weed, Herbe à la Coupure, Herbe aux Charpentiers, Herbe Militaire, Old Man’s Pepper, Devil’s Nettle, Devil’s Plaything, Bad Man’s Plaything, Dog Daisy, Dog Fennel, Green Arrow, Noble Yarrow, Plumajillo, Milenrama, Millefeuille, Millefolium, Millefolii Herba, Millefolii Flos, Achillée, Achillée Millefeuille, Achillée Boréale, Achillea, Achillea borealis, Achillea lanulosa, Achillea magna, Achillea millefolium, Yarrow Essential Oil
Glycoalkaloids and bitter plant alkaloids including achilleine and related Achillea constituents; volatile oils containing monoterpenes and sesquiterpenes; sesquiterpene lactones including achillin-type compounds; hydrolysable tannins; aromatic oils and irritant compounds that may contribute to gastrointestinal upset, increased urination, and contact dermatitis or allergy-type reactions in sensitive animals
Vomiting, diarrhea, drooling, colic or abdominal discomfort, reduced appetite, depression, drowsiness, lethargy, increased urination, skin irritation, itching, rash, contact dermatitis, and possible allergy-type reactions in sensitive animals. Large or repeated ingestion may cause more persistent gastrointestinal upset, dehydration, weakness, or worsened signs in animals sensitive to plants in the Asteraceae family. Pregnant animals should not be allowed to ingest Dog Daisy because of concern for uterine effects or miscarriage risk.
Dog Daisy, Achillea millefolium, is more widely known as Yarrow or Common Yarrow. It is a flowering perennial in the Asteraceae family, formerly called Compositae, and is common across much of North America, Europe, and temperate parts of the Northern Hemisphere. It is easily recognized by its flat-topped clusters of small white to pink flowers and its soft, finely divided, fern-like leaves, which give rise to names such as Milfoil, Thousand-Leaf, and Thousand-Seal.
Dog Daisy has a long history of use as a topical medication for wounds such as cuts and abrasions. The genus name Achillea is traditionally linked to Achilles, the Greek hero of the Trojan War and the greatest warrior of Homer’s Iliad, who reportedly carried the plant with his army to treat battle wounds. This long association with bleeding, wounds, and battlefield medicine explains many of the plant’s older names, including Soldier’s Woundwort, Bloodwort, Nosebleed, Staunchweed, Carpenter’s Weed, Herbe à la Coupure, and Herbe Militaire.
A flowering plant common to the entirety of the lower 48 states, Dog Daisy can be found in grasslands, meadows, roadsides, lawns, disturbed soil, open forests, pasture edges, and ornamental herb gardens. It spreads by rhizomes and seed, and once established it can persist in mowed areas, dry soils, and low-maintenance landscapes. Because of this wide distribution, exposure is most likely to occur when dogs graze on weedy lawns, cats chew dried herb material, horses browse mixed pasture, or pets encounter yarrow in herb gardens or cut-flower arrangements.
The herb is purported to have diaphoretic properties, meaning the power to cause increased perspiration; astringent properties, meaning it may aid in clotting when applied externally; and stimulant-like properties. The primary alkaloid traditionally associated with Dog Daisy, achilleine, has been reported to be haemostatic, reducing clotting time without obvious toxic side effects in some historical or experimental contexts. It has also been reported to lower blood pressure and was isolated and used as a quinine substitute for the prevention of malaria at the turn of the century.
Those medicinal associations should be understood in context. Dog Daisy is a historically important herb, but medicinal use does not mean the plant is safe for pets to graze or chew freely. Many plants used in folk medicine contain bitter, biologically active compounds that can irritate the digestive tract or affect sensitive animals. In Dog Daisy, the practical toxic concerns are glycoalkaloids and related bitter constituents, volatile oils, sesquiterpene lactones, hydrolysable tannins, and aromatic compounds that may contribute to vomiting, diarrhea, drooling, reduced appetite, depression, increased urination, and dermatitis.
The tannins and bitter aromatic oils in Dog Daisy tend to make the plant unappealing, which helps limit large ingestions. Most dogs, cats, and horses are unlikely to consume enough fresh yarrow to create life-threatening intoxication. For that reason, Dog Daisy poisoning is generally considered uncommon and usually low-to-moderate in severity. The expected signs are gastrointestinal upset, especially vomiting and diarrhea, along with drooling, colic-like discomfort, depression, drowsiness, lethargy, and sometimes increased urination.
Skin exposure is also relevant. Yarrow and related Asteraceae plants can cause contact dermatitis in sensitive individuals or animals, especially when crushed plant material, sap, or essential oil contacts the skin. Pets that roll in mowed yarrow, rub against dense patches, lick crushed leaves from their coat, or are exposed to concentrated yarrow essential oil may develop itching, redness, rash, or irritation. Allergy-prone animals or animals sensitive to ragweed, chrysanthemums, daisies, marigolds, and other members of the Asteraceae family may be more reactive.
This Asteraceae allergy connection is one of the most important plant-specific cautions for Dog Daisy. A pet that is already sensitive to ragweed-like plants or that develops dermatitis from other composite flowers may react more strongly to yarrow than another animal would. In those animals, even modest exposure can produce more pronounced itching, licking, rash, inflamed skin, or mouth irritation. Essential oils and concentrated extracts are a separate concern because they may contain much higher levels of volatile compounds than the living plant.
Pregnancy is another important caution. Dog Daisy has a long medicinal history that includes effects on bleeding, uterine tone, and reproductive physiology in traditional-use discussions. For that reason, pregnant animals should not be allowed to ingest the plant, and it is not recommended that nursing young be allowed to nurse from an animal that may have recently consumed a significant amount of Dog Daisy or concentrated yarrow products. The concern is not that every small nibble will cause miscarriage, but that unnecessary exposure in pregnant or nursing animals is avoidable and should be prevented.
There is also a practical bleeding and surgery caution. Because Dog Daisy has been associated historically with haemostatic, astringent, and blood-related effects, and because herbal preparations may have variable biologic activity, it is reasonable to avoid yarrow ingestion before surgery or in animals with bleeding disorders, clotting problems, anticoagulant medication, or planned procedures. A conservative approach is to allow at least two weeks between known meaningful consumption of Dog Daisy or yarrow products and elective surgery, unless a veterinarian advises otherwise.
Most ordinary exposures are not expected to be lethal. A pet would generally need to consume an unusually large amount of plant material, or a concentrated preparation such as essential oil or extract, to face severe consequences. However, “rarely lethal” does not mean “safe.” Vomiting and diarrhea can still cause dehydration, small animals can become weak quickly, horses may develop colic-like signs, and dermatitis can become uncomfortable enough to require treatment.
The safest practical approach is to prevent pets and grazing animals from eating Dog Daisy, especially in large amounts, and to avoid concentrated yarrow products unless specifically directed by a veterinarian. Remove the plant from high-traffic pet areas if animals chew it repeatedly, keep dried herbal material and essential oils out of reach, and consult a veterinarian if a pet develops persistent vomiting, diarrhea, depression, dermatitis, or abnormal urination after exposure.
Immediate Response to Dog Daisy Ingestion
- Remove the Source: Prevent further ingestion by removing the pet or grazing animal from Dog Daisy, Yarrow, Common Yarrow, flowers, leaves, stems, dried herb material, clippings, pasture patches, herb-garden plants, or any remaining plant material.
- Identify the Plant: Confirm whether the plant is Achillea millefolium, commonly called Dog Daisy, Yarrow, Common Yarrow, Milfoil, Thousand-Leaf, Soldier’s Woundwort, Bloodwort, Nosebleed, Old Man’s Pepper, or Devil’s Nettle.
- Check for Concentrated Products: Determine whether the exposure involved the fresh plant, dried herb, tea, tincture, capsule, salve, or yarrow essential oil. Concentrated extracts and essential oils may create more risk than ordinary plant nibbling.
- Remove Plant Material from the Mouth: If ingestion was recent and it is safe to do so, remove visible leaves, flowers, stems, or dried plant fragments from the mouth.
- Rinse the Mouth: Flush the mouth gently with water to remove bitter plant material, aromatic oils, tannins, or irritating residue.
- Wash Skin Exposures: If crushed plant material, sap, or essential oil contacted the skin, paws, lips, muzzle, belly, or fur, wash the area with mild soap and water to reduce the risk of itching, redness, rash, or contact dermatitis.
- Watch for Symptoms: Monitor for drooling, vomiting, diarrhea, abdominal discomfort, colic, reduced appetite, depression, drowsiness, lethargy, increased urination, itching, rash, skin irritation, weakness, or dehydration.
- Contact Veterinary Help if Needed: Consult a veterinarian, emergency veterinary clinic, Pet Poison Helpline, or another animal poison-control professional if a large amount was eaten, if concentrated yarrow products were involved, if symptoms are persistent or severe, or if the exposed animal is very small, young, elderly, pregnant, nursing, medically fragile, allergy-prone, scheduled for surgery, or already ill.
Inducing Vomiting and Decontamination
- Usually Low-to-Moderate Severity: Life-threatening intoxication from ordinary Dog Daisy or Yarrow ingestion is unlikely, and most cases are expected to involve gastrointestinal upset, drowsiness, increased urination, or dermatitis rather than severe poisoning.
- Getting Plant Material Out May Help: If a dog has recently swallowed a meaningful amount of fresh or dried Dog Daisy, removing remaining plant material from the stomach may reduce continued gastrointestinal irritation and exposure to bitter alkaloids, tannins, and volatile oils.
- Spontaneous Vomiting May Occur: The pet may vomit naturally because the plant is bitter, aromatic, and irritating to the stomach and intestines.
- Inducing Vomiting in Dogs Only: If ingestion was recent and the dog is alert, breathing normally, able to swallow, and not already vomiting repeatedly, weak, collapsed, severely depressed, tremoring, seizuring, showing abnormal heart signs, or neurologic signs, a veterinarian or animal poison-control professional may recommend inducing vomiting with fresh 3% hydrogen peroxide.
- Cat Warning: Hydrogen peroxide should not be used to induce vomiting in cats unless a veterinarian specifically directs it. Cats are more prone to irritation and complications from hydrogen peroxide, and home vomiting attempts may create more risk than benefit.
- Do Not Induce Vomiting in an Unstable Animal: Vomiting should not be attempted in any animal that is weak, collapsed, sedated, having trouble breathing, unable to swallow normally, already vomiting repeatedly, showing tremors, seizures, abnormal heart signs, severe depression, or neurologic signs.
- Activated Charcoal: Activated charcoal is rarely needed for ordinary plant nibbling but may be considered by a veterinarian or poison-control professional if a large amount, dried herb, concentrated extract, or essential oil was ingested.
- Gastric Lavage: Gastric lavage is not expected for routine Dog Daisy exposure, but a veterinarian may consider controlled decontamination in an unusual large-volume or concentrated-product ingestion.
Symptomatic Care and Treatment
- No Specific Antidote: There is no specific antidote for Dog Daisy or Yarrow ingestion. Treatment is symptomatic and supportive.
- Hydration: Ensure the pet receives adequate fluids to reduce the risk of dehydration caused by vomiting, diarrhea, drooling, or reduced drinking.
- Monitor Vomiting and Diarrhea: Repeated vomiting, persistent diarrhea, blood in stool, inability to keep water down, weakness, or worsening lethargy should prompt veterinary evaluation.
- Dermatitis Care: Itching, redness, rash, licking, or skin irritation after contact with Dog Daisy should be washed gently. Persistent or severe dermatitis may require veterinary treatment.
- Allergy-Prone Animals: Animals sensitive to ragweed, chrysanthemums, daisies, marigolds, or other Asteraceae plants may develop stronger skin, mouth, or gastrointestinal reactions and should be monitored more closely.
- Pregnancy and Nursing Caution: Pregnant animals should not be allowed to ingest Dog Daisy because of concern for uterine effects or miscarriage risk. Consult a veterinarian if a pregnant or nursing animal consumed a meaningful amount.
- Surgery and Bleeding Caution: Because yarrow has blood-related historical uses and possible effects on clotting or bleeding, notify the veterinarian if an animal scheduled for surgery has recently consumed Dog Daisy, yarrow herb, or yarrow supplements.
- Gastrointestinal Protection:
- Kapectolin: To alleviate gastrointestinal upset and diarrhea, Kapectolin may be given at a dose of 1 to 2 ml/kg four times daily to help coat and protect the stomach lining.
- Sucralfate: Sucralfate may be used for gastrointestinal irritation because it reacts with stomach acid to form a paste-like protective barrier between irritated tissue and stomach contents.
- Dogs greater than 60 lbs: 1g every 6 to 8 hours.
- Dogs less than 60 lbs: 0.5g every 6 to 8 hours.
- Cats: 0.25g every 8 to 12 hours.
Lawn, Pasture, Herb-Garden, and Essential-Oil Prevention
- Control Repeated Grazing: Dog Daisy is common in lawns, meadows, roadsides, and pastures. Prevent dogs, cats, horses, and grazing animals from repeatedly eating patches of yarrow.
- Clean Up Clippings: Do not leave freshly cut, pulled, dried, or mowed yarrow where pets or livestock can chew it.
- Do Not Feed Herbal Waste: Dog Daisy leaves, flowers, dried herb, tea leftovers, or garden clippings should not be fed to horses, goats, sheep, cattle, rabbits, or other animals.
- Keep Essential Oils Away from Pets: Yarrow essential oil and concentrated herbal extracts should be kept out of reach of pets. Concentrated products are not equivalent to a small nibble of the fresh plant.
- Watch Asteraceae-Sensitive Pets: Animals with known sensitivity to ragweed, daisies, chrysanthemums, marigolds, or related plants should be kept away from Dog Daisy where possible.
- Use Caution Before Surgery: Avoid unnecessary yarrow exposure before planned procedures, and tell the veterinarian about any recent ingestion of Dog Daisy or yarrow supplements.
Prognosis and Recovery
- General Outlook: Serious intoxication from ordinary Dog Daisy ingestion is rare, and fatal poisoning is unlikely from normal plant nibbling.
- Expected Recovery: Most pets recover with removal of the plant, hydration, monitoring, and supportive care once vomiting, diarrhea, or skin irritation are controlled.
- Higher-Risk Cases: Prognosis becomes more guarded if a very large amount was eaten, if a concentrated extract or essential oil was involved, if the animal is pregnant, medically fragile, severely allergy-prone, dehydrated, or unable to keep fluids down.
- Veterinary Care: Veterinary evaluation is recommended when symptoms are persistent, severe, involve marked depression or dehydration, include significant dermatitis, involve pregnancy or surgery concerns, or when the plant identity is uncertain.
- Prevention: Prevent further ingestion, keep pets away from heavy yarrow growth, store dried herbs and essential oils securely, and remove clippings from animal-accessible areas.