Dang Gui is a fascinating medicinal that has been subjected to many types of pao zhi over the centuries. The part of the root that is used is traditionally considered to affect Dang Gui’s actions, and the various different types of pao zhi further accentuate certain effects. In the modern day, the wine-processed (jiu zhi) and unprocessed (sheng) forms are most common but additional pao zhi methods such as stir-frying with earth and char-frying are also used.

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Historically, stir-frying was the first method used; soaking in wine first emerged slightly later in the Tang dynasty (618-907 CE). Many processing methods emerged in the Song dynasty (960-1280 CE), such as wine-washing, moistening with wine then stir-frying with rice, wine-soaking, wine stir-frying, and vinegar stir-frying. In the Ming and Qing dynasties, many other methods surfaced, including: wine-steaming, wine-boiling, stir-frying with ginger juice, stir-frying with water that rice has been washed in, stir-frying with earth, charring, and processing with adjuvants such as child’s urine, black bean juice, wu zhu yu, or peony juice.

Just as different pao zhi methods affect Dang Gui’s properties, the part of the root is also thought to affect its medicinal action. In the Song dynasty, it was said that one should “use one joint from the head if blood-supplementation is desired; use the tail if pain-relieving and blood-breaking is desired.” In the Yuan dynasty, it was said that “the head stops bleeding, the body harmonizes the blood, and the rootlets break the blood.” By the Ming and Qing dynasties, we find statements such as “the head stops bleeding and moves upwards, the tail breaks the blood and moves downwards, the body nourishes the blood and stays in the center, and the whole [root] quickens the blood and is mobile.”

Unprocessed Dang Gui is moistening and good for supplementing the blood, regulating menstruation, and moistening the intestines to free the stool; it is used for blood vacuity with constipation.

Wine-processing strengthens the blood-moving nature of Dang Gui (as well as its blood-supplementing and menstruation-regulating actions), so the wine-processed form is preferred to free menstruation and relieve pain; it is used to treat blood vacuity with blood stasis.

The product that is stir-fried with earth is used to supplement the blood without moistening the intestines, and it is used for patients with blood vacuity and sloppy stool, episodic abdominal pain, and vacuity cold of the middle burner.

The charred form is used to stop bleeding and harmonize the blood, and is used for flooding and spotting as well as profuse menstruation.