Costus Root — Classic Formulas
Mu Xiang · Radix Aucklandiae
Primary Actions
- Moves Qi and alleviates pain in the middle burner - Mu Xiang is a premier aromatic regulator for epigastric and abdominal fullness, bloating, cramping, belching, and cold or food-stagnation digestive pain when obstruction rather than deficiency is the main problem.
- Strengthens the Spleen and promotes digestion - a small dose is often added to tonic or damp-transforming formulas so the rich ingredients do not create stagnation, making it particularly useful when weak transport and retained food coexist.
- Regulates intestinal Qi and relieves dysenteric tenesmus - Mu Xiang is classically valued for painful urgent bowel movements, diarrhea with incomplete evacuation, or damp-heat dysentery patterns in which the intestines are blocked and the bowels cannot descend smoothly.
- Promotes Qi movement through the San Jiao and lower burner - beyond the Stomach and intestines, Mu Xiang is used for chest, flank, or lower-abdominal constrained pain when cold and stagnant Qi impede the normal up-and-down movement of the torso.
Classic Formulas
- Mu Xiang Bing Lang Wan (木香槟榔丸) - classic accumulation-breaking formula in which Mu Xiang drives Qi through the intestines for food stagnation, constipation, and dysenteric tenesmus with marked abdominal oppression.
- Xiang Sha Liu Jun Zi Tang (香砂六君子汤) - Spleen-tonifying formula where Mu Xiang prevents cloying tonics from worsening fullness, nausea, and post-prandial bloating while gently restoring digestive movement.
- Xiang Lian Wan (香连丸) - pairing of Mu Xiang with Huang Lian for damp-heat dysentery, abdominal cramping, and the classic li ji hou zhong sensation of urgent but incomplete evacuation.
- Mu Xiang Shun Qi Tang (木香顺气汤) - broad Qi-regulating formula that resolves dampness, distension, and wandering abdominal or torso pain by restoring the smooth movement of Qi through the San Jiao.
Classical Text References
- Ben Cao Hui Yan describes Guang Mu Xiang as the master herb for treating Qi, harmonizing Stomach Qi, descending Lung Qi, dispersing Liver Qi, warming Kidney Qi, and governing Qi movement above and below, inside and outside the body.
- Ben Cao Jing Shu cautions against its use in Yin deficiency, internal heat, Lung heat from deficiency, and major Qi collapse, emphasizing that a moving aromatic should not be mistaken for a general tonic.
- Historical materia medica notes that the modern pharmacopoeial Mu Xiang became clearly fixed as the imported Asteraceae root during the Tang period, while confusion with Aristolochia-type Qing Mu Xiang later created clinically important safety problems that modern identification standards now aim to prevent.