Chaihu Jia Longgu Muli Tang was first introduced 1,850 years ago in Zhang Zhongjing’s classical prescription manual, Discourse on Disorders Caused by Cold (Shanghan lun). It represents a famous modification of the more common Xiao Chaihu Tang, with a specific focus on severe mental and neurological disorders. Since the original prescription includes lead, a potent sedating agent yet nowadays also recognized as a toxic heavy metal, this formula is rarely used in China anymore. In Japan, however, a non-lead version of Chaihu Jia Longgu Muli Tang approved by the Ministry of Health is prescribed very frequently. The Classical Pearls version of this formula employs the exact traditional dosage ratios of all ingredients, but naturally follows the Japanese model and does not include lead. Due to the broad clinical range covered by the bupleurum family of formulas, this remedy can be used to treat a wide variety of (generally more severe) digestive and brain chemistry disorders.