【Nature and flavor and meridians】Bitter in taste, slightly cold in nature. Enters the liver meridian.
 【Effects】Clears heat, cools blood, disperses blood stasis and relieves pain.
 [Indications] It is used for heat entering the blood, warm toxicity causing rash, vomiting blood and epistaxis, red and swollen eyes, liver depression and flank pain, amenorrhea and dysmenorrhea, abdominal pain due to lumps and masses, injuries from falls, carbuncles and ulcers.
 【Usage and Dosage】6-12g.
 [Contraindications] Do not use with Veratrum. People with blood deficiency should take it with caution.
 【Medical records】
 "Shennong's Herbal Classic": "Peony root has a bitter and flat taste. It can cure abdominal pain caused by pathogenic qi, eliminate blood stasis, break up hard masses, treat cold and heat, hernia, and relieve pain... It grows in rivers and valleys."
 "Ben Cao Cong Xin" says: "White peony root... white peony root can benefit the spleen and drain wood from the soil, while red peony root can disperse evil and relieve stagnation in the blood. The red and white peony roots are different depending on the color of the flower, and the single-petal ones are used as medicine."
 Tao Hongjing: "Red peony root has a slight benefit. It is used in common prescriptions to relieve pain, but it does not reduce the use of angelica root." ("Compendium of Materia Medica")
 Li Dongyuan: "Red peony root can break up blood stasis and treat abdominal pain, and relieve fever. It is often used in Zhongjing's prescriptions because it can calm cold and heat and promote urination." ("The Image of Using Medicine")
 【Predecessors release medicine】
 Miao Xiyong: "The color of wood peony is red. Red is used to break up and disperse, and is used to clear and smooth. It specifically enters the liver and blood, so it is used to treat abdominal pain caused by evil qi. It is used to remove blood stasis and break up hard masses. Blood stasis will cause chills and fever, and blood circulation will stop the chills and fever. Blood stasis and hernia are all caused by blood stasis. If the blood in the limbs is stagnant, the stasis will be harmonious and the hernia will disappear. It cools the liver and thus smoothes the blood vessels. The liver governs blood. Entering the liver to circulate blood will disperse bad blood and expel evil blood. If the nutrient qi is not harmonious, it will flow back into the flesh and form carbuncles. If blood circulation and cooling blood are used, the carbuncle will disappear. Women's menstruation belongs to the liver meridian of the foot jueyin. It enters the liver to circulate blood, so it is used to treat amenorrhea. The liver opens the eyes. Red eyes are caused by liver heat. Acid and cold can cool the liver, so it can treat red eyes. Intestinal wind and blood are caused by damp-heat intestinal blood. Intestinal wind will stop by itself if the blood is cool." ("Compendium of Materia Medica")
 Jia Suoxue: "Red peony root is bitter and can purge, with sourness entering the liver, specifically purging liver fire. The liver stores blood, so it can be used to clear heat and cool blood. It is added to Dongran Decoction to treat sudden red eyes; added to Rhinoceros Horn Decoction to clear vomiting and bleeding. It is added to Shenxian Huoming Decoction to attack various toxic heat congestion and dissipate toxic gas; added to Liuyi Shunqi Decoction to purge large intestine obstruction and make blood flow smoothly. Because it can descend, it is good at moving blood stasis, regulate women's menstruation, eliminate blood stasis and promote lactation; because it is cold in nature, it can relieve heat and irritability, remove internal dampness, and promote diuresis and laxative. It is more bitter than white peony root, but it can purge without tonifying." ("Pharmaceutical Chemistry")
 Huang Gongxiu: "Red peony root and white peony root have similar main treatments, but white peony root has the power to restrain yin and benefit the blood, while red peony root only has the meaning of dispersing evil and promoting blood circulation; white peony root can purge wood in the earth, while red peony root can activate stagnation in the blood. Therefore, for patients with abdominal pain, blood stasis, hernia, amenorrhea and red eyes caused by accumulated heat, this herb can cool blood and remove blood stasis, which is very different from white peony root which is mainly for tonification without purgation." ("Compendium of Materia Medica")