Tu Yizhihao, a Chinese herbal medicine, is the whole plant of Achillea wilsoniana Heimerl ex Hand.-Mazz., a plant belonging to the Asteraceae family. It has the effects of dispelling wind and dampness, promoting blood circulation, relieving pain, detoxifying, and reducing swelling. It is commonly used to treat rheumatic pain, stomachaches, toothaches, bruises and swelling from injuries, abdominal pain caused by menstrual disorders, abscesses, and snake or insect bites.
Tu Yizhihao is a perennial herbaceous plant, 30-100cm tall. It has a short rhizome. The stem is erect, with longitudinal grooves, densely covered with soft hairs above the middle, and branched on the upper part. Infertile branches are often found in leaf axils.
The leaves are opposite, sessile, and elongated-linear, 4-6.5cm long and 1-2cm wide. They are pinnately divided on both sides, with a leaf axis about 1.5mm wide. The leaf edges are entire or have 1-2 small teeth. The lobes and teeth are elliptical and lanceolate, with small cartilaginous tips on the upper surface and soft hairs sparsely distributed on the upper surface and densely distributed on the lower surface along with glandular dots.
The inflorescence is head-like, with multiple umbel-like cymes; the involucre is wide bell-shaped or semi-spherical, 4-6mm in diameter; the involucre consists of three layers of imbricate bracts, with the outer layer being short, ovate-lanceolate, with a midrib, membranous edges, brown in color, and tufted with soft hairs; the receptacle is boat-shaped, and the involucre is boat-shaped.
The marginal flowers are ligulate and female, 6-16 in number, with white or light pink petals and 3 shallow teeth at the apex; the central and bisexual flowers are pale yellow or white, with flattened tubes and glandular dots. The achene is elongated and wedge-shaped, 2.5mm long, with wings and no pappus. The flowering and fruiting period is from July to September.
The efficacy of Tu Yizhihao
It has a pungent and cold nature and is toxic.
① "Wenshan Chinese Herbal Medicine": "Pungent and numbing in taste, cold in nature, and toxic."
② "Yunnan Simao Chinese Herbal Medicine Selection": "Cold in nature, bitter and pungent in taste, mildly toxic."
③ "Yunnan Chinese Herbal Medicine": "Pungent and numbing in taste, warm in nature, highly toxic."
The effects of Tu Yizhihao
It promotes blood circulation, dispels wind, reduces swelling, and relieves pain. It is used to treat injuries, rheumatic pain, stomachaches, toothaches, abdominal pain caused by menstrual disorders, acute mastitis, and abscesses.
① "Wenshan Chinese Herbal Medicine": "Dispels wind and dampness, reduces swelling and stops bleeding. It is used to treat hematemesis, blood in the stool, rheumatic pain, back pain, external bleeding from injuries, and toothaches."
② "Yunnan Simao Chinese Herbal Medicine Selection": "Clears heat, detoxifies, dispels blood stasis, and relieves pain. It is used to treat injuries, fractures, rheumatic pain, hemoptysis in pulmonary tuberculosis, bronchitis, tonsillitis, hematemesis, amenorrhea, dysmenorrhea, abdominal masses, and external bleeding from injuries or snake bites."
③ "Yunnan Chinese Herbal Medicine": "Promotes blood circulation, reduces swelling, relieves pain, and stops inflammation and bleeding."
