酸苦微寒，无毒。酒洗用。
《本经》除血痹，破坚积，寒热疝瘕，止痛，利小便。
发明 赤芍药性专下气，故止痛不减当归。苏恭以为赤者利小便、下气，白者止痛和血
，端不出《本经》除血痹，破坚积，止痛，利小便之旨。其主寒热疝瘕者，善行血中之滞也
，故有瘀血留著作痛者宜之，非若白者酸寒收敛也。其治血痹，利小便之功，赤、白皆得应
用。要在配合之神，乃着奇绩耳。
苦辛平，无毒。酒洗去碱土，曝干。勿见火。
《本经》主寒热、中风、螈 、惊痫、邪气，除症坚、瘀血留舍肠胃五脏，疗痈疮。
发明 牡丹皮入手足少阴厥阴，治血中伏火，故相火胜肾，无汗骨蒸为专药。《本经》
主寒热、中风、螈 、惊痫等证，以其味辛气窜，能开发陷伏之邪外散。惟自汗多者勿用，
为能走泄津液也。痘疹初起勿用，为其性专散血，不无根脚散阔之虑。王安道云∶志不足者
，足少阴病也。故仲景肾气凡用之。后人惟知黄 治相火，不知丹皮之功更胜也。又症坚瘀
血留舍肠胃五脏，及阴虚吐血衄血必用之药，以能行瘀血而又能安好血，有破积生新，引血
归经之功，故犀角地黄汤用之。凡妇人血崩及经行过期不净，属虚寒者禁用。又赤者利血，
白兼补气，亦如赤、白芍药之义，诸家言其性寒，安有辛香而寒者乎。
Sour and bitter, slightly cold, non-toxic. Use after washing with wine.
*Shennong Bencao Jing* (Divine Farmer's Materia Medica) records that it eliminates blood bi (obstruction due to blood stasis), breaks down hard accumulations, treats cold-heat hernia and masses, relieves pain, and promotes urination.
Invention: Chishao Yao (Radix Paeoniae Rubra, Red Peony Root) has a specific action of directing Qi downward; therefore, its pain-relieving effect is comparable to that of Danggui (Radix Angelicae Sinensis). Sugong believed that the red variety promotes urination and directs Qi downward, while the white variety relieves pain and harmonizes blood. This does not exceed the purport of *Shennong Bencao Jing* regarding Chishao Yao’s functions of eliminating blood bi, breaking down hard accumulations, relieving pain, and promoting urination. Its treatment of cold-heat hernia and masses stems from its ability to effectively move stagnation within the blood vessels. Thus, it is suitable for pain caused by retained blood stasis, unlike the white variety which possesses sour-cold astringent properties. Regarding the treatment of blood bi and promotion of urination, both red and white varieties can be applied. The key lies in appropriate combination, which yields miraculous results.
Bitter and pungent, neutral, non-toxic. Wash with wine to remove alkaline soil, then dry in the sun. Avoid exposure to fire.
*Shennong Bencao Jing* records that it treats cold-heat, wind-stroke, convulsions, epilepsy, and pathogenic factors; eliminates hard masses and blood stasis lodged in the intestines, stomach, and five zang organs; and treats carbuncles and sores.
Invention: Mudan Pi (Cortex Moutan Radicis, Tree Peony Bark) enters the Hand-Shaoyin (Heart), Foot-Shaoyin (Kidney), and Jueyin (Liver) meridians. It treats latent fire within the blood and is a specific remedy for ministerial fire hyperactivity causing kidney yin deficiency and steaming bone without sweat. The conditions recorded in *Shennong Bencao Jing*, such as cold-heat, wind-stroke, convulsions, and epilepsy, are treated because its pungent flavor and penetrating aroma can expel trapped pathogens outward. It should not be used in patients with spontaneous sweating, as it disperses body fluids. It should not be used at the initial stage of chickenpox or smallpox rashes, because its nature specifically disperses blood, raising concerns about the rash losing its defined base and spreading widely. Wang Andao stated: Insufficiency of willpower belongs to diseases of the Foot-Shaoyin meridian. Therefore, Zhang Zhongjing frequently used it in Shenqi Wan (Kidney Qi Pill). Later generations only knew that Huangbai (Cortex Phellodendri, Phellodendron Bark) clears ministerial fire, unaware that Mudan Pi’s efficacy is superior. Furthermore, it is an essential herb for hard masses, blood stasis lodged in the intestines, stomach, and five zang organs, as well as for hematemesis and epistaxis due to yin deficiency. This is because it can move blood stasis while stabilizing blood, possessing the functions of breaking down accumulations, generating new blood, and guiding blood back to the meridians. Hence, it is used in Xijiao Dihuang Tang (Rhinoceros Horn and Rehmannia Decoction). It is contraindicated for women with metrorrhagia or delayed menstruation with incomplete discharge belonging to deficiency-cold patterns. Additionally, similar to the distinction between Chishao Yao and Baishao Yao, the red variety benefits blood while the white variety tonifies Qi. Various schools state that Mudan Pi is cold-natured, but how can a pungent and aromatic herb be cold?