【Nature and flavor】Bitter, pungent, slightly cold.
 [return through meridians] returns the heart, liver, and kidney meridians.
 [Effects] Clears heat and cools blood, promotes blood circulation and removes blood stasis, and relieves deficiency fever.
 [Indications] Heat entering the blood, warm poison causing rashes, vomiting blood and epistaxis, hot at night and cool in the morning, no sweat and bone steaming, amenorrhea and dysmenorrhea, injuries and pains from falls, carbuncles, swellings and sores.
 【Usage and Dosage】6-12g.
 [Precautions for use] Do not use if you have diarrhea due to spleen and stomach deficiency.
 【Medical records】
 "Ben Jing": "It cures cold and heat, stroke, convulsions, epilepsy, evil spirits, removes blood stasis in the intestines and stomach, soothes the five internal organs, and treats carbuncle."
 "Ben Jing Shu Zheng" states: "Peony bark enters the heart and clears blood vessels, which is similar to cinnamon twig. However, cinnamon twig has a warm qi, so it clears cold stagnation in the blood vessels, while peony bark has a cold qi, so it clears heat accumulation in the blood vessels."
 "Ming Yi Bie Lu" (Famous Doctors' Records): "It can cure headaches caused by seasonal qi, exogenous heat, five kinds of fatigue, headache and back pain caused by fatigue, wind-induced aphonia, and epilepsy."
 "Medicine Properties": "It can treat coldness, relieve various pains, and treat blocked meridians and back pain in women."
 "Rihuazi Materia Medica" says: "It removes evil spirits, brightens the complexion, clears the blood vessels, discharges pus, regulates menstruation, eliminates blood stasis, strengthens tendons and bones, removes rheumatism, aborts the fetus, and treats all cold and hot blood qi after childbirth."
 "Southern Yunnan Materia Medica" says: "It can break up blood, promote blood circulation, eliminate diseases of tumors and masses, and remove heat from the blood."
 "Introduction to Medicine": "It can relieve latent fire, nourish true blood and qi, and break up accumulation of stagnation."
 "Compendium of Materia Medica": "It can regulate blood, generate blood, and cool blood. It can treat fire hidden in the blood and eliminate restlessness and heat."
 "Zhenzhu Nang": "It can treat blood accumulation in the stomach and intestines, epistaxis, hematemesis, and bone steaming without sweating."
 【Predecessors release medicine】
 "Compendium of Materia Medica" states: "Peony bark can treat hidden fire in the blood of the four meridians of the hands and feet, Shaoyin and Jueyin. Hidden fire is Yin fire, and Yin fire is Xiang fire. Ancient prescriptions only use this to treat Xiang fire, so Zhongjing Shenqi Pills use it. Later generations used Huangbo to treat Xiang fire, not knowing that Peony bark is more effective. Red flowers are beneficial, while white flowers are tonic, but few people understand this, so it is better to distinguish them."
 "Ben Cao Jing Shu" says: "Peony bark tastes bitter and slightly pungent, and its qi is cold but non-toxic. Pungent tastes to disperse lumps, and bitter and cold tastes to remove blood heat. It enters the blood and is an essential medicine for cooling blood heat. Cold and heat are symptoms of yin deficiency and blood heat. Stroke, spasm, convulsions, and epilepsy are all caused by yin deficiency, internal heat, and insufficient blood. When the heat is gone, the blood is cool, and when the coolness is gone, new blood is generated and yin qi is restored. When yin qi is restored, the fire is not inflammatory and there is no sign of wind caused by heat, so it is the main treatment. Carbuncle is caused by heat congestion and blood stasis. Cooling blood and promoting blood circulation can cure carbuncle. Pungent taste can disperse blood, and bitter taste can purge heat, so It can remove evil qi from the blood, and treat blood stasis in the intestines and stomach. The organs belong to yin and store essence, they like coolness and hate heat, and when the heat is removed, the five organs will be at peace. "Bielu" also treats headaches caused by seasonal qi, fatigue, and pain in the head and waist, which are the functions of relieving heat and cooling blood. Zhen Quan also treats blocked meridians, blood dripping and waist pain, which are all signs of blood drying up due to heat. The fire hidden in the blood cannot be removed without this, so it can treat bone steaming without sweating, and children's smallpox and blood heat. Dongyuan said that for those with heart deficiency, heat accumulation in the stomach and intestines, severe heart fire, and insufficient heart qi, peony bark should be the main ingredient, which is also the meaning. "
 "Compendium of Materia Medica": "Mr. Shen Baike said: According to "Master Shen's Prescription", using peony bark with angelica and cooked rehmannia can replenish blood; with curcuma and peach kernel, it can break blood; with raw rehmannia, scutellaria, and coptis can cool blood; with cinnamon and roasted ginger, it can warm blood; with Chuanxiong and white peony, it can regulate blood; with Achyranthes bidentata and safflower, it can activate blood; with wolfberry and donkey-hide gelatin, it can generate blood; with Cyperus rotundus, Achyranthes bidentata, Angelica Root, and Chuanxiong, it can also regulate qi and harmonize blood. If the fire in the yin is not combined with Anemarrhena asphodeloides and white peony, it is not suitable for the treatment of fire in the yin. Medicine cannot cure it; all postpartum diseases cannot be cured without Radix Angelicae Pubescentis, Rhizoma Chuanxiong and Rhizoma Leonuri. If you want to relieve the Qi and soothe the liver, you can use Radix Citrus Reticulatae and Radix Bupleuri. If you want to relieve phlegm and depression, you can use Radix Fritillariae and Rhizoma Pinelliae. If you want to use it to discharge pus, expel poison and cool the blood in ulcers, you must use frankincense, myrrh, angelica dahurica, Radix Notopterygii, Fructus Forsythiae and Flos Lonicerae to help. Peony bark can clear the heart, nourish the kidney, harmonize the liver, benefit the pericardium, and treat the hidden fire in the blood of the four meridians. It is a blood Qi medicine. It is good for treating women's meridians. It can cure obstruction and postpartum blood. It can also cure nosebleed, vomiting blood, metrorrhagia, blood stasis, and all blood and qi diseases. It has a fragrant aroma, which can regulate qi and promote blood circulation; it tastes bitter, which can lower qi and stop bleeding; it is cool in nature, which can harmonize blood and produce blood; it tastes pungent, which can push out old blood and bring in new blood. Therefore, Zhen Quan's prescription can treat women whose blood is about to dry up due to heat, back pain, night heat and thirst, using the Four Substances plus Peony Root. It is the most effective. Ancient prescriptions also use this to treat the attack of the fire of the yang and fever caused by deficiency of the yin. According to the Ben Jing, the main symptoms of cold and heat, stroke, spasm, convulsion, epilepsy and other evil qi are all related to the blood. However, cold and heat, and stroke refer to the stroke caused by the heat of typhoid fever entering the blood chamber, not the stroke caused by deficiency of qi and phlegm in the elderly. The text first uses the words cold and heat, followed by spasm, convulsion, epilepsy, and so on. Moreover, spasm, convulsion, and epilepsy are caused by the heat of the blood, and cold and heat are also related to the Shaoyang.    
 "Depei Materia Medica" says: "Both Danpi and Chuanbai can remove the fire in water, but one can clear dry fire and the other can reduce evil fire, so they are not compatible. The kidney hates dryness, and if it is dry, water will not return to its origin. It is appropriate to use pungent herbs to moisten it and cool herbs to clear it, with Danpi as the strength. The kidney wants to be strong, but if it is hurt by fire, it will not be strong, so it is appropriate to supplement it according to its nature, with Chuanbai as the messenger."
 "Compendium of Materia Medica" states: "People in the world use Phellodendron chinense to treat yang fire, but they do not know that the effect of Cortex Moutan is even better. Phellodendron chinense is bitter, cold and dry, which will hurt the stomach at first and hurt the yang in the long run. Its bitter and dry nature only exists, but its effect of replenishing yin is very small. Cortex Moutan can drain the fire in the yin, so that the fire retreats and the yin grows. Therefore, it can enter the Shaoyin meridian of the foot and assist in nourishing and replenishing. It is far superior to Phellodendron chinense."
 "Compendium of Materia Medica": Red Cortex Moutan has a strong effect on blood circulation, while white Cortex Moutan has a slow effect on blood circulation. In short, its nature and flavor are mild and it has no tonic properties. However, it is slightly cool and spicy, and can harmonize blood, cool blood, generate blood, eliminate irritability and heat, and is good at removing blood stasis. When stagnation is removed, the stagnant heat will be relieved, so it can also reduce fever. People who use this herb use it to remove blood stasis without being harsh.
 " Chongqingtang Essays": Although the bark of moutan is not a hot medicine, it has a fragrant and pungent smell. It is a blood-qi medicine that specializes in blood circulation and blood stasis, so it can cause abortion and eliminate bad habits. The so-called ability to stop bleeding means that when the blood stasis is removed, new blood will naturally settle down, not that the bark of moutan can really stop bleeding. For those with blood deficiency and wind-cold, it can be used to induce sweating. If there is no blood stasis but the blood is hot and running wildly, or if there is blood deficiency without external infection, it cannot be used. Only when it is added to the yin-nourishing agent, the yin medicine can be used to promote circulation without stagnation, and it can also achieve the function of cooling blood. Therefore, it is the best product for those who suffer from dysentery due to yin deficiency and heat entering the blood. However, it has a fragrant and turbid smell, which is very easy to vomit. People with weak stomachs will vomit after taking it. None of the "Compendium of Materia Medica" mentioned it, so those who use it should examine it carefully.