Paeoniae Radix rubra (chi shao) ... is strictly draining due to its bitterness, so that it invigorates the blood, expels stagnation, and stops pain; its slight sourness retains its affinity for the Liver so that it enters the blood aspect of the Liver, where its coldness cools heat in the blood. It is thus used for rashes due to warm pathogen disease causing heat in the blood, and swollen toxic sores, as explained in Essays on Medicine Esteeming the Chinese and Respecting the Western: "it is superior for transforming stasis, thus those who treat sores and abscesses often use it for its ability to transform toxic hot blood stasis without causing the formation and perforation of pus." Essentials of the Materia Medica notes that it: 'specifically drains Liver fire and disperses noxious blood. It treats abdominal pain, firm accumulations, blood painful obstruction, bulging disorders, and mobile abdominal masses, amenorrhea, Intestinal wind, swollen sores, and reddened eyes - all these are the effect of dispersing and draining." - Bensky: Chinese Herbal Medicine Materia Medica, 3rd ed.