Atractylodes Macrocephalae Paeoniae Radix is composed of 4 herbs, namely, Atractylodes macrocephala, Pericarpium Citri Reticulatae, Paeonia lactiflora, and Fenghuang, which are used to strengthen the spleen, dispel dampness and stop diarrhea, and dredge the liver to move qi and alleviate pain by regulating the body’s qi mechanism. Atractylodes Macrocephalae Paeoniae Radix is also known as Painful Diarrhea Essentials Formula, which treats painful diarrhea caused by spleen deficiency and liver depression, which is abdominal pain and diarrhea due to disharmony between the liver and spleen, and malfunctioning of the spleen’s movement. Atractylodes Macrocephalae Paeoniae Radix is a representative formula for the treatment of painful diarrhea, which is characterized by abdominal pain with diarrhea, and the pain is relieved after diarrhea. In the formula, Atractylodes macrocephala is bitter, sweet and warm, tonifying the spleen and drying dampness as the principal medicine; Paeonia lactiflora is sour, sweet and cold, softening the liver and easing the pain as the ministerial medicine; Pericarpium ternatum is used as the adjuvant to regulate qi and drying dampness and to awaken the spleen and the stomach; Fenghuang combines with Paeonia lactiflora to ease the liver and relieve depression, and combines with Atractylodes macrocephala to stimulate the spleen’s yang, remove dampness and stop diarrhea, and it also serves as the spleen meridian-inducing medicine. In addition, modern research has found that atractylodes macrocephala has analgesic and antidiarrheal, anti-inflammatory, anti-experimental gastric ulcers and other pharmacological effects, and can be used for the treatment of inflammatory bowel disease and so on. The drug needs to be used under the guidance of a doctor, do not take it blindly on your own.