Blood stasis is a pathological product formed after the stagnation of blood flow. Blood runs in the blood vessels, and according to where it stays, stasis blood can be divided into stasis blood formed when blood runs poorly in the blood vessels and is blocked in the meridians and organs, and stasis blood formed when blood leaves the blood vessels and stays in the body due to bleeding. Regardless of the type of stagnant blood, it is a causative factor and can lead to the formation of stagnant blood due to trauma, qi stagnation, qi deficiency, blood cold, blood heat, fluid deficiency, phlegm obstruction, etc. Once stasis of blood is formed, it can block the flow of qi, affect the normal operation of blood, and prevent the production of new blood, resulting in pain, tingling, immobility, aggravation at night, formation of lumps, bleeding, bruising of the lips and nails, petechiae on the tongue, cardiac arrhythmia, insomnia, amnesia, and rough skin.