Herbal Monograph
Yarrow
Achillea millefolium L.
Asteraceae
Master of the blood — a versatile wound herb, fever ally, and aromatic bitter...
Overview
Plant Description
Achillea millefolium is a hardy, aromatic, perennial herb growing 30–80 cm (occasionally to 100 cm) tall from a creeping rhizome. Stems are erect, simple or sparingly branched above, angular, and finely pubescent. Leaves are alternate, lanceolate to oblong in outline, 5–15 cm long, bipinnately to tripinnately dissected into numerous fine, feathery segments (hence 'millefolium' — thousand leaves), giving a fern-like appearance. Basal leaves are petiolate; upper leaves are sessile and progressively smaller. Flower heads are arranged in dense, flat-topped terminal corymbs, each capitulum 4–6 mm across, with 5 (occasionally 3–8) short, broad ray florets (white, occasionally pink to deep rose) surrounding a cluster of yellowish-white disc florets. The involucre is ovoid with imbricate, keeled phyllaries having scarious margins. Achenes are compressed, oblong, approximately 2 mm, without pappus. The entire plant is strongly aromatic with a complex camphoraceous, slightly sweet-herbaceous scent.
Habitat
Grows in a wide range of habitats including meadows, grasslands, roadsides, field edges, waste ground, pastures, and open woodlands. Prefers well-drained, moderately fertile soils but tolerates poor, dry, sandy, or gravelly substrates. Thrives in full sun to partial shade. Found from sea level to alpine elevations (up to 3,500 m in mountainous regions). Extremely drought-tolerant once established. Hardy to USDA zones 2–9. Tolerates a wide soil pH range (5.5–8.0).
Distribution
Native to temperate regions of the Northern Hemisphere across Europe, western and central Asia, and North America. One of the most widely distributed flowering plants in the world. Found throughout Europe (including the British Isles, Scandinavia, and the Mediterranean basin), across Russia and central Asia to the Himalayas, and throughout North America from Alaska to Mexico. Widely naturalized in temperate regions of the Southern Hemisphere including Australia, New Zealand, and South America. Major commercial cultivation occurs in Germany, Hungary, Poland, Bulgaria, and other European countries.
Parts Used
Aerial parts (flowering herb)
Preferred: Dried herb for infusion or tincture (1:5 in 45% ethanol)
The flowering aerial parts (Millefolii herba) are the primary medicinal material specified in all major Western pharmacopeial monographs (Commission E, WHO, BHP, EMA). The whole herb — including leaves, stems, and inflorescences — is used. The herb contains the full spectrum of therapeutically active constituents: volatile oil, sesquiterpene lactones, flavonoids, tannins, and alkamides.
Flowers (inflorescences)
Preferred: Dried flowers for infusion or as a component of medicinal tea blends
The flowers alone (Millefolii flos) are specified separately in the Commission E monograph and some European pharmacopeias. The flower heads contain higher concentrations of volatile oil and flavonoids compared to the stems and leaves. Used preferentially in some traditions for internal therapeutic applications, particularly for digestive and fever indications.
Key Constituents
Volatile oil (essential oil)
The volatile oil is responsible for yarrow's aromatic, carminative, anti-inflammatory, and antimicrobial properties. The composition varies markedly by chemotype, geographic origin, and ploidy level — European diploid populations tend to produce more chamazulene, while North American polyploid populations have more camphor and 1,8-cineole. The chamazulene content directly correlates with anti-inflammatory potency. For therapeutic use, chamazulene-rich chemotypes are preferred.
Sesquiterpene lactones
The sesquiterpene lactones contribute to yarrow's bitter digestive-stimulating action, anti-inflammatory activity, and part of the antimicrobial profile. They stimulate digestive secretions via bitter taste receptor activation and have demonstrated anti-inflammatory activity via NF-kB inhibition and reduction of pro-inflammatory cytokines in vitro.
Flavonoids
The flavonoid fraction is central to yarrow's antispasmodic, anti-inflammatory, and vasoprotective actions. Apigenin's smooth muscle relaxant activity supports the traditional use for menstrual and gastrointestinal cramping. Luteolin provides potent anti-inflammatory activity. Rutin strengthens capillaries and supports the hemostatic and astringent indications.
Tannins (condensed and hydrolysable)
The tannin content underlies yarrow's astringent and hemostatic actions. Tannins precipitate surface proteins on mucous membranes and damaged tissue, forming a protective layer that reduces bleeding, secretion, and inflammation. This supports the traditional topical wound-healing use and the internal astringent action on the gastrointestinal and uterine mucosa.
Alkamides (isobutylamides)
The alkamides are minor constituents but may contribute to immunomodulatory effects and peripheral circulatory stimulation. Their presence supports the traditional use of yarrow as a diaphoretic in fever management.
Phenolic acids and other constituents
These minor constituents contribute collectively to yarrow's broad therapeutic profile. The salicylates and caffeic acid derivatives add to the anti-inflammatory and choleretic effects. Achilleine has historical significance as the compound once thought primarily responsible for yarrow's hemostatic reputation, though modern understanding attributes this more to the tannin fraction.
Herbal Actions
Promotes perspiration
One of the premier diaphoretic herbs in Western herbalism. Promotes perspiration when taken as a hot infusion during febrile illness, aiding the body's natural fever response. The volatile oil and alkamide fractions stimulate peripheral circulation and sweating. Commission E approves for loss of appetite and dyspeptic complaints; the BHP specifically lists the diaphoretic action. Traditionally combined with Sambucus nigra (elderflower) and Mentha × piperita (peppermint) for fever management.
[1, 6, 10]Reduces inflammation
Broad-spectrum anti-inflammatory activity mediated by multiple constituent classes: chamazulene inhibits leukotriene B4 synthesis and 5-lipoxygenase; sesquiterpene lactones suppress NF-kB-mediated inflammatory gene expression; flavonoids (luteolin, apigenin) inhibit COX-2 and pro-inflammatory cytokine production. Commission E approves for dyspeptic complaints and external use in wound healing, both of which rely on the anti-inflammatory action.
[1, 2, 9]Tightens and tones tissue, reduces secretions
The tannin fraction (2–4%) provides significant astringent activity, tightening and toning mucosal tissues. This underlies the hemostatic action (topical wound staunching), the antidiarrheal effect, and the reduction of excessive mucosal secretions. The BHP lists yarrow as an astringent and the Commission E approves external use for wound healing based partly on this action.
[1, 6, 10]Relieves smooth muscle spasm
Flavonoids (particularly apigenin) relax smooth muscle in the gastrointestinal tract and uterus via direct musculotropic action and possible calcium channel modulation. Supports the Commission E-approved indication for dyspeptic complaints (gastrointestinal cramping) and the traditional use for menstrual cramps (dysmenorrhea). The antispasmodic action is well-supported by pharmacological studies.
[1, 2, 9]Stimulates digestive secretions via bitter taste receptors
The sesquiterpene lactones (achillin, achillicin) activate bitter taste receptors (T2R), stimulating vagally mediated secretion of saliva, gastric acid, bile, and pancreatic enzymes. This bitter tonic action supports the Commission E-approved indication for loss of appetite and dyspeptic complaints. Yarrow is classified as an 'aromatic bitter' due to the combined presence of bitter sesquiterpene lactones and aromatic volatile oil.
[1, 6, 9]Promotes wound healing
Promotes wound healing through multiple mechanisms: astringent tannins form a protective barrier over wounds, anti-inflammatory constituents reduce wound inflammation, and antimicrobial volatile oil components help prevent infection. Commission E approves external use for wound healing and the sitz bath application for painful lower pelvic cramps. The mythological association with Achilles healing his soldiers' battle wounds reflects a deep historical tradition of topical wound use.
[1, 6, 10]Stimulates or increases menstrual flow
Promotes and regulates menstrual flow. The antispasmodic flavonoids relieve uterine cramping while the astringent tannins modulate excessive menstrual bleeding. This dual action — moving stagnant or delayed menses while reducing hemorrhage — is expressed in the traditional characterization of yarrow as 'master of the blood.' The emmenagogue action is the basis for the AHPA class-2b (avoid in pregnancy) safety classification.
[3, 6, 9]Kills or inhibits the growth of microorganisms
The volatile oil demonstrates antimicrobial activity against a range of gram-positive and gram-negative bacteria and some fungi in vitro. 1,8-Cineole, camphor, and other monoterpenes contribute to this action. Supports the traditional topical wound-care application.
[5, 9]Lowers blood pressure
Mild peripheral vasodilatory action attributed to flavonoids and volatile oil constituents. May contribute modestly to blood pressure reduction through improved peripheral circulation and diaphoresis. Not a primary antihypertensive herb but may support cardiovascular function in formulae.
[6]Relieves intestinal gas and bloating
The volatile oil provides carminative action, relieving intestinal gas and bloating. Works synergistically with the antispasmodic and bitter actions to address functional dyspepsia. The aromatic volatile oil relaxes the smooth muscle of the gastrointestinal tract while promoting coordinated peristalsis.
[1, 6]Therapeutic Indications
Digestive System
Loss of appetite (anorexia)
Commission E specifically approved yarrow for 'loss of appetite.' The bitter sesquiterpene lactones stimulate digestive secretions (saliva, gastric acid, bile) via bitter taste receptor activation, reflexively improving appetite. WHO monograph concurs. Standard indication for aromatic bitter herbs.
[1, 2]Dyspeptic complaints (functional dyspepsia)
Commission E approved for 'dyspeptic complaints' including bloating, flatulence, mild gastrointestinal cramping, and a feeling of fullness. The combined bitter, carminative, antispasmodic, and anti-inflammatory actions address multiple facets of functional dyspepsia. WHO monograph supports this indication.
[1, 2, 4]Mild gastrointestinal spasm and colic
The flavonoid-mediated antispasmodic action (particularly apigenin) directly relaxes gastrointestinal smooth muscle. BHP lists yarrow for gastrointestinal colic. Often combined with Matricaria chamomilla (chamomile) and Mentha × piperita (peppermint) for digestive cramping.
[6, 9, 10]Cardiovascular System
Fever management (febrile illness)
Traditional diaphoretic use for fever is one of yarrow's most well-established indications. Taken as a hot infusion, yarrow promotes peripheral vasodilation and perspiration, supporting the body's natural fever response. The BHP lists yarrow for 'feverish conditions, common cold.' The classic formula combines yarrow, elderflower, and peppermint for fevers and upper respiratory infections.
[6, 9, 10]Peripheral circulatory support
Yarrow gently stimulates peripheral circulation through vasodilatory volatile oil components and flavonoids. Used traditionally for cold extremities and as a supportive herb in circulatory formulas. Milder than true circulatory stimulants like Zingiber officinale (ginger) or Capsicum spp.
[6, 10]Hypertension (mild, supportive)
The mild hypotensive action may provide gentle supportive benefit in mild hypertension, particularly when associated with peripheral vascular tension. Not a primary antihypertensive herb. Used in formulae rather than as a standalone treatment.
[6]Reproductive System
Dysmenorrhea (painful menstruation)
The antispasmodic flavonoids (apigenin) relieve uterine cramping while the anti-inflammatory action reduces prostaglandin-mediated menstrual pain. Commission E approves yarrow in sitz bath for 'painful, cramp-like conditions of psychosomatic origin in the lower part of the pelvis in women.' BHP and Hoffmann list yarrow for dysmenorrhea.
[1, 6, 10]Menorrhagia (excessive menstrual bleeding)
The astringent tannins help reduce excessive uterine bleeding. Yarrow has been used traditionally for menorrhagia and metrorrhagia (irregular uterine bleeding). The 'amphoteric' blood action — simultaneously able to staunch excessive bleeding and promote delayed or stagnant menses — is a hallmark of yarrow's traditional profile.
[6, 9]Pelvic congestion and cramps (sitz bath)
Commission E specifically approves yarrow for external use as a sitz bath for 'painful, cramp-like conditions of psychosomatic origin in the lower part of the pelvis in women.' The combined antispasmodic, anti-inflammatory, and circulatory actions provide relief when absorbed through the pelvic mucosa.
[1]Skin / Integumentary
Wound healing (cuts, abrasions, minor trauma)
Commission E approves yarrow for external use for wound healing. The vulnerary action combines astringent hemostasis (staunching bleeding), anti-inflammatory activity (reducing wound inflammation), and antimicrobial protection. This is one of yarrow's oldest and most celebrated uses — the genus name Achillea derives from the Greek hero Achilles, who, according to legend, used yarrow to treat his soldiers' battle wounds.
[1, 2, 6]Nosebleed (epistaxis)
One of yarrow's common names is 'nosebleed plant,' reflecting the widespread folk practice of inserting a rolled yarrow leaf into the nostril to stop nosebleeds. Paradoxically, yarrow was also used traditionally to induce nosebleeds as a form of bloodletting headache remedy. The astringent tannins are responsible for the hemostatic effect.
[6, 7]Respiratory System
Common cold and upper respiratory infections
The diaphoretic action (hot infusion) supports fever resolution, while the anti-inflammatory and mild antimicrobial actions address upper respiratory symptoms. BHP lists yarrow for 'feverish conditions, common cold.' The classic elderflower-yarrow-peppermint combination remains a standard Western herbal approach to acute febrile upper respiratory illness.
[6, 10]Allergic rhinitis (hay fever)
The astringent and anti-inflammatory actions may help reduce nasal mucosal secretion and inflammation in allergic rhinitis. Traditional use; limited clinical evidence.
[6]Urinary System
Energetics
Temperature
cool
Moisture
dry
Taste
Tissue States
hot/excitation, damp/stagnation, damp/relaxation
Yarrow is energetically cooling and drying with a complex taste profile — predominantly bitter, pungent (aromatic), and astringent. In Western energetic terms (following Hoffmann, Wood, and the physiomedicalist tradition), yarrow addresses hot, inflammatory tissue states (via its cooling anti-inflammatory action) and damp, stagnant conditions (via its drying astringent and bitter tonic actions). The diaphoretic action is 'cooling' — it opens the periphery to release trapped heat during fever, a classic diaphoretic cooling strategy. Matthew Wood describes yarrow as an 'amphoteric' remedy for the blood: it can both stop bleeding (styptic/astringent) and move stagnant blood (emmenagogue/circulatory stimulant), reflecting its traditional epithet 'master of the blood.' This amphoteric quality — simultaneously astringent and stimulant — is characteristic of yarrow's complex and balancing energetic profile.
Traditional Uses
European Herbalism (Classical and Folk)
- Wound healing and hemostasis — one of the most widely used wound herbs across European folk traditions, applied as poultices, compresses, and direct leaf application to cuts and battlefield injuries
- Fever management — hot yarrow infusion as a diaphoretic for fevers, colds, and influenza, often combined with elderflower and peppermint (the classic 'fever tea')
- Digestive complaints — bitter tonic for poor appetite, indigestion, bloating, and colic
- Menstrual regulation — used for both excessive menstrual bleeding and delayed or suppressed menses
- Nosebleed treatment — rolled leaves inserted into nostrils to stop epistaxis (hence 'nosebleed plant'); conversely, used to induce nosebleed as a headache remedy in some traditions
- Toothache — chewed fresh leaves applied to aching teeth for analgesic effect
"Dioscorides (1st century CE) recorded yarrow (as 'stratiotes chiliophyllos' — soldier's thousand-leaf) for treating wounds and controlling hemorrhage. Gerard (1597) wrote: 'The leaves being put into the nose, do cause it to bleed, and easeth the paine of the megrim.' Culpeper (1653) noted: 'It is held by most to be the same plant with which Achilles cured the wounds of his soldiers.' Mrs. Grieve (1931): 'It is employed in the form of an infusion... for colds, in obstructed perspiration, the commencement of fevers, and in measles and other eruptive diseases.'"
Native American Medicine
- Analgesic — infusion or poultice for headaches, body aches, and arthritic pain across numerous tribal traditions
- Wound treatment and hemostasis — crushed leaves applied directly to wounds (Cherokee, Chippewa, Iroquois, and many others)
- Digestive aid — infusion for stomach complaints, nausea, and loss of appetite
- Cold and fever remedy — infusion used as a diaphoretic and to relieve cold symptoms
- Ear and toothache — juice or decoction applied locally for earache and toothache (Miwok, Paiute)
- Ceremonial use — burned as smudge for purification and protection; considered a sacred medicine in many traditions
"Yarrow was one of the most widely used medicinal plants among Native American peoples, with documented use by over 40 tribal groups. Moerman's Native American Ethnobotany database records extensive use across the Chippewa, Cherokee, Iroquois, Blackfoot, Miwok, Paiute, and dozens of other nations for analgesic, hemostatic, cold/fever, and ceremonial purposes."
Western Herbalism (Modern Phytotherapy)
- Fever management — diaphoretic infusion for acute febrile illness, combined with elderflower and peppermint in the classic 'fever tea'
- Dyspepsia and appetite stimulation — aromatic bitter tonic for functional digestive complaints
- Menstrual disorders — dysmenorrhea, menorrhagia, and as a uterine tonic in hormonal support formulas
- Wound healing — external applications (washes, compresses, sitz baths) for cuts, abrasions, and pelvic pain
- Upper respiratory infections — combined with other diaphoretics for colds and influenza
- Cardiovascular support — mild peripheral vasodilator and hypotensive in circulatory formulas
"Hoffmann (2003): 'Yarrow is one of the best diaphoretic herbs and is a standard remedy for aiding the body to deal with fevers. It lowers blood pressure due to a dilation of the peripheral vessels. It stimulates the digestion and tones the blood vessels.' Mills & Bone (2013) classify it with actions: 'diaphoretic, astringent, anti-inflammatory, antispasmodic, bitter tonic, vulnerary, urinary antiseptic.'"
Traditional Chinese Medicine (TCM)
- Not a classical TCM herb — Achillea millefolium is not included in the standard Chinese materia medica
- Occasionally referenced in modern integrative Chinese herbal texts for hemostasis and wound healing
- The related species Achillea alpina (shi) is used in some Chinese regional traditions for similar hemostatic and anti-inflammatory indications
"While A. millefolium itself is not part of the classical Chinese materia medica, the genus Achillea has representation in Chinese regional medicine. The I Ching (Book of Changes) famously uses dried yarrow stalks for divination, reflecting the cultural significance of Achillea species in Chinese tradition, though this is divinatory rather than medicinal."
[6]
Modern Research
Anti-inflammatory activity
In vitro and in vivo studies confirm significant anti-inflammatory activity of yarrow extracts and isolated constituents, supporting the traditional and Commission E-approved indications.
Findings: Multiple studies demonstrate that yarrow extracts inhibit key inflammatory mediators: chamazulene inhibits leukotriene B4 synthesis and 5-lipoxygenase; the flavonoids apigenin and luteolin inhibit COX-2 expression and reduce prostaglandin E2 and pro-inflammatory cytokine (TNF-alpha, IL-1beta, IL-6) production; sesquiterpene lactones inhibit NF-kB nuclear translocation. Aqueous and ethanolic extracts showed dose-dependent anti-inflammatory activity in carrageenan-induced paw edema models in rats, with efficacy comparable to indomethacin at higher doses.
Limitations: Most data is preclinical (in vitro and animal models). Human clinical trials specifically examining anti-inflammatory endpoints are lacking. Variability in extract composition across chemotypes limits generalizability.
Antispasmodic and gastrointestinal effects
Pharmacological studies confirm the antispasmodic action on gastrointestinal and uterine smooth muscle, supporting the Commission E approval for dyspeptic complaints.
Findings: Isolated guinea pig ileum and rat uterus preparations demonstrate that yarrow flavonoids (particularly apigenin and luteolin glycosides) produce dose-dependent relaxation of acetylcholine- and histamine-induced contractions. The mechanism involves direct musculotropic relaxation and possible calcium channel modulation rather than anticholinergic blockade. Crude aqueous extracts also demonstrated spasmolytic activity, confirming that the active principles are extractable in tea preparations.
Limitations: Isolated tissue experiments do not fully model in vivo conditions. Clinical trials measuring gastric motility or symptom relief in dyspepsia patients are limited.
Antimicrobial activity
The essential oil and various extracts demonstrate antimicrobial activity against a range of pathogens.
Findings: Candan et al. (2003) and subsequent studies demonstrated that yarrow essential oil exhibits antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Klebsiella pneumoniae with MIC values ranging from 0.25 to 4.0 mg/mL. Antifungal activity against Candida albicans and Aspergillus niger was also demonstrated. The monoterpenes 1,8-cineole and camphor are primary contributors. Methanolic extracts showed broader antimicrobial spectrum than aqueous extracts.
Limitations: In vitro antimicrobial activity does not directly translate to clinical antimicrobial efficacy. MIC values for yarrow are generally higher (less potent) than pharmaceutical antibiotics. Insufficient clinical evidence for antimicrobial indications.
Wound healing
Preclinical studies support the traditional wound-healing use, demonstrating enhanced re-epithelialization and anti-inflammatory effects in wound models.
Findings: Animal wound models (excision and incision) treated with topical yarrow extract ointments demonstrated significantly accelerated wound closure, increased tensile strength, and enhanced collagen deposition compared to untreated controls. The mechanism involves the combined anti-inflammatory, antimicrobial, and astringent actions. Hydroalcoholic extracts were more effective than aqueous extracts, suggesting the lipophilic constituents (volatile oil, flavonoid aglycones) contribute significantly.
Limitations: Animal studies only. No controlled human clinical trials on wound healing. Extract standardization and optimal concentration for topical preparations are not established.
Hepatoprotective and choleretic activity
Limited preclinical evidence suggests yarrow extracts may have hepatoprotective and bile-stimulating effects.
Findings: Rat studies showed that yarrow extracts provided partial protection against carbon tetrachloride-induced hepatotoxicity, reducing elevated liver enzymes (ALT, AST) and histological damage. Choleretic activity (increased bile flow) was demonstrated in animal models, consistent with the bitter tonic classification and traditional use for digestive complaints.
Limitations: Very limited data. No human trials. Hepatoprotective effect is modest compared to established hepatoprotectants like Silybum marianum (milk thistle). Mechanism not fully elucidated.
[9]
Preparations & Dosage
Infusion (Tea)
Strength: Approximately 1:40 to 1:75 herb to water
Pour 150 mL of boiling water over 1–2 teaspoons (2–4 g) of dried yarrow herb or flowers. Cover and steep for 10–15 minutes. Strain. For diaphoretic fever use, drink hot. For digestive bitter tonic use, drink warm or at room temperature 30 minutes before meals. For the classic 'fever tea,' combine equal parts yarrow, elderflower (Sambucus nigra), and peppermint (Mentha × piperita).
2–4 g of dried herb per cup, 3–4 cups daily
3–4 times daily between meals (bitter tonic) or as needed during acute febrile illness (diaphoretic)
For acute conditions (fever, cold): until symptoms resolve, typically 3–7 days. For chronic digestive complaints: 2–4 weeks, then reassess.
Children over 6: half the adult dose. Not recommended for children under 6 without professional guidance.
The infusion is the most traditional and widely used preparation for yarrow. Cover the cup during steeping to prevent loss of volatile oil via steam. The infusion should have a clear golden-green color with a distinctly aromatic, bitter-herbaceous taste. Commission E dosage: 4.5 g dried herb daily or 3 g dried flowers daily for internal use.
Tincture
Strength: 1:5 in 45% ethanol (dried herb); 1:2 in 65% ethanol (fresh herb)
Tincture of dried yarrow herb in ethanol-water solution. Macerate 1 part dried herb in 5 parts 45% ethanol for 2–4 weeks, shaking daily. Press and filter. A fresh herb tincture (1:2 in 65% ethanol) is also used by some practitioners.
2–4 mL of 1:5 tincture (45% ethanol) three times daily
Three times daily, taken in a small amount of water
2–8 weeks for chronic conditions; short-term for acute presentations
Not generally recommended for children in tincture form due to alcohol content. Use infusion instead.
The tincture extracts both water-soluble (flavonoids, tannins) and lipophilic (volatile oil, sesquiterpene lactones) constituents more effectively than an infusion. The BHP specifies 1:5 in 45% ethanol. The tincture has a strongly bitter, aromatic taste.
Poultice
Strength: External wash: double-strength infusion (8 g per 150 mL). Sitz bath: 100 g per 20 L.
For wound healing and external application: prepare a strong infusion (double strength — 4–8 g per 150 mL) or use fresh crushed leaves applied directly to the wound. For sitz bath (Commission E-approved): add 100 g of dried herb to 20 liters of warm water (approximately 37°C). Alternatively, prepare a strong infusion of 100 g herb in 1–2 liters of boiling water, strain, and add to the bath water. Soak for 10–20 minutes.
External: apply fresh herb or warm poultice directly to affected area. Sitz bath: 100 g dried herb per 20 L water, 10–20 minutes, as needed.
Poultice: 2–3 times daily as needed. Sitz bath: once daily or as directed.
Until wound heals or symptoms resolve
External application: suitable for children over 2 years. Sitz bath: not typically indicated for children.
Commission E approves the external use for 'wound healing' and sitz bath for 'painful, cramp-like conditions of psychosomatic origin in the lower part of the pelvis in women.' Fresh yarrow leaves crushed and applied directly to cuts is one of the oldest folk remedies in European and Native American traditions.
Essential Oil
Strength: Pure essential oil, diluted to 1–3% for topical use
Yarrow essential oil is obtained by steam distillation of the fresh or dried flowering herb. High-chamazulene oils have a deep blue color. Used externally only — diluted in a carrier oil (1–3% concentration) for topical anti-inflammatory and wound-healing applications.
External use only: 1–3% dilution in carrier oil (3–9 drops per 15 mL carrier oil). Not for internal use.
Apply to affected area 2–3 times daily
As needed for symptomatic relief
Not recommended for children under 6. Use at half concentration (0.5–1%) for children over 6.
Yarrow essential oil is chemically variable. High-chamazulene (blue) oils are preferred for anti-inflammatory applications. Note that the thujone content of some chemotypes warrants caution — do not use internally. The essential oil is considerably more concentrated than the herb and should only be used externally in appropriate dilution.
[9]
Safety & Interactions
Class 2b
Not to be used during lactation (AHPA Botanical Safety Handbook)
Contraindications
Yarrow belongs to the Asteraceae family and contains sesquiterpene lactones, which are potent contact allergens and can cause allergic contact dermatitis, allergic rhinitis, and potentially anaphylaxis in sensitized individuals. Cross-reactivity is documented with other Asteraceae plants including ragweed (Ambrosia), chamomile (Matricaria), arnica (Arnica), echinacea (Echinacea), and chrysanthemum. Patients with known Asteraceae allergy should avoid all yarrow preparations.
AHPA classifies yarrow as Class 2b: 'Not to be used during pregnancy.' The emmenagogue action and potential uterine stimulant effects pose a theoretical risk of miscarriage or premature labor. No adequate human safety data exists for pregnancy use. Commission E does not contraindicate in pregnancy specifically but the emmenagogue reputation warrants avoidance.
Drug Interactions
| Drug / Class | Severity | Mechanism |
|---|---|---|
| Warfarin (Anticoagulants (vitamin K antagonists)) | theoretical | Yarrow contains trace coumarins and salicylates that could theoretically potentiate anticoagulant effects. The astringent/hemostatic action would counteract this, creating an unpredictable interaction profile. |
| Aspirin and NSAIDs (Antiplatelet and anti-inflammatory agents) | theoretical | Salicylate content could theoretically augment aspirin's antiplatelet effect. Anti-inflammatory constituents may have additive effects with NSAIDs. |
| Antihypertensive medications (Blood pressure-lowering agents) | minor | The mild hypotensive action of yarrow could theoretically have additive effects with antihypertensive drugs. |
| Barbiturates and sedative medications (CNS depressants) | theoretical | Apigenin has low-affinity GABA-A receptor binding activity. At very high doses, theoretical potentiation of sedative effects. |
| Lithium (Mood stabilizers) | theoretical | The mild diuretic action of yarrow could theoretically reduce lithium clearance, increasing serum lithium levels. |
Pregnancy & Lactation
Pregnancy
unsafe
Lactation
insufficient data
AHPA classifies yarrow as Class 2b: 'Not to be used during pregnancy.' The emmenagogue action and traditional reputation as a uterine stimulant contraindicates use during pregnancy due to the theoretical risk of miscarriage or premature labor. The thujone content, though low, provides additional reason for avoidance. No adequate human safety data exists for pregnancy or lactation. Mills & Bone recommend avoiding during pregnancy. Insufficient data on excretion into breast milk; caution is advised during breastfeeding.
Adverse Effects
References
Monograph Sources
- [1] Blumenthal, M., Busse, W.R., Goldberg, A., et al.. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines — Millefolii herba / Millefolii flos. American Botanical Council / Integrative Medicine Communications (1998) . ISBN: 978-0-9655555-0-0
- [2] World Health Organization. WHO Monographs on Selected Medicinal Plants, Volume 4: Herba Millefolii. World Health Organization, Geneva (2010) . ISBN: 978-92-4-154704-4
- [3] Gardner, Z., McGuffin, M. (eds.). American Herbal Products Association's Botanical Safety Handbook, 2nd Edition. CRC Press (2013) . ISBN: 978-1-4665-1695-3
- [4] European Medicines Agency, Committee on Herbal Medicinal Products (HMPC). Community herbal monograph on Achillea millefolium L., herba. EMA/HMPC/290964/2009 (2012)
Clinical Studies
- [5] Candan, F., Unlu, M., Tepe, B., Daferera, D., Polissiou, M., Sökmen, A., Akpulat, H.A.. 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 . DOI: 10.1016/S0378-8741(03)00149-1 . PMID: 12860311
Traditional Texts
- [6] Hoffmann, D.. Medical Herbalism: The Science and Practice of Herbal Medicine. Healing Arts Press (2003) . ISBN: 978-0-89281-749-8
- [7] Grieve, M.. A Modern Herbal. Jonathan Cape / Harcourt Brace (1931) . ISBN: 978-0-486-22798-6
- [8] Moerman, D.E.. Native American Ethnobotany. Timber Press (1998) . ISBN: 978-0-88192-453-4
Pharmacopeias & Reviews
- [9] Mills, S., Bone, K.. Principles and Practice of Phytotherapy: Modern Herbal Medicine, 2nd Edition. Churchill Livingstone / Elsevier (2013) . ISBN: 978-0-443-06992-5
- [10] British Herbal Medicine Association. British Herbal Pharmacopoeia. BHMA (1996) . ISBN: 978-0-903032-09-5
Last updated: 2026-03-02 | Status: review
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