A strong-smelling, aromatic herb, arising from a creeping, stoloniferous rootstock, 30-75 cm high. Leaves 15-25 cm long, oblong, pinnatisect, segments lanceolate, acute, sharply toothed; flower-heads yellow, in dense flattopped corymbs; achenes greenish white, 1.5 mm, cylindrical-obovoid, pappus minute.

Abortifacient, vermifuge (essential flower and leaf oil); tonic, stimulant, emmenagogue, diaphoretic and insect-repellent (decoction of dried leaves and flowertops)

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Plants for a Future
King's American Dispensatory

Beta-thujones (essential oil); 1,8-cineole, camphor, chlorogenic acid, vibernitol (leaf); terpinoids (aerial part); alpha-pinene, alpha-terpinene, apigenin, borneol, bornyl-acetate, caffeic acid, caryophyllene, chlorogenic acid, eupatilin, gamma-terpinene, parthenolide, piperitone, quercetin (plant)

Rheumatism, ulcers (chronic), for gout, as an abortifacient and vermifuge (essential flower and leaf oil); maladies of the liver, gall bladder and the bile duct, in treating strangury, kidney weaknesses, in dyspepsia, with troublesome flatulence, hysteria, jaundice, fevers (plant); to treat amenorrhoea and painful dysmenorrhoea and as an anthelmintic, especially for children (leaf infusion and whole plant);in diphtheria, acute inflammations of the throat, and in epidemic catarrh (spray or inhalation of plant decoction).

Oil of tansy is a gastro-intestinal and nerve poison, and in overdoses has caused epileptiform convulsions, profound coma, and death by paralysis of the breathing organs (asphyxiation). Lesser doses may increase the pulse rate, dilate the pupils, and cause severe vomiting and purging with colicky pain. Doses above fifteen drops are dangerous. Most deaths have occurred from its use in attempts at abortion.

Chandel et al., Biodiversity in Medicinal and Aromatic Plants in India.