Red yeast is a kind of traditional Chinese medicine, which has the effect of eliminating food, strengthening the spleen, etc. Patients should follow the doctor’s instructions and apply it reasonably. Red yeast is mainly cultivated and fermented on round-grained rice, and its shape is like broken rice, with brownish-red appearance, pinkish-red cross-section, and brittle texture. Red yeast is a traditional Chinese medicine with sweet taste and warm nature, which belongs to the liver, spleen and large intestine meridians. It mainly has the effects of activating blood circulation and removing blood stasis (promoting blood circulation and eliminating blood stasis in the body), invigorating the spleen and eliminating food. It can be used clinically for post-partum dyspepsia, abdominal pain with stagnation and stagnation, red-white dysentery (increased frequency of stools, mucus and pus and blood in feces), bruises and injuries, and food stagnation (accumulation of indigested food in the stomach) and bloating. The adverse reactions and contraindications of red quatrefoil are not clear, patients are advised to use red quatrefoil reasonably under the guidance of a doctor, and may also be used in combination with other traditional Chinese medicines as prescribed by the doctor.